JP2002357594A - Device and method for identifying magnetic particles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and method for identifying magnetic particles, by which magnetic particles composed of a plurality of kinds of materials can be identified and separated individually, even when the kinds of materials to be detected are many and which can be applied to affinity coupling. SOLUTION: The device for identifying magnetic particles identifies magnetic particles 2 which have specific magnetic susceptibility by using a pipe 1, through which the particles 2 are passed and a magnetic field generating device which generates a magnetic field in the pipe 1. A plurality of magnetic particles 2, having different magnetic susceptibility, is introduced into the pipe 1 by means of an inlet mechanism 3. The speeds of the particles 2 in the pipe 1 are changed by generating the magnetic field, and the changed speeds of the particles 2 are detected by means of magnetic particle detectors 6 and 7 and a speed detector 8. The particles 2 are identified, based on the speed changes of the particles 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to magnetic particles that can be controlled by different types and that can attach genetic substances or other target substances to the surface of a magnetic particle. The present invention relates to a magnetic particle discriminating apparatus and a magnetic particle discriminating method which can be separated and applied to affinity binding.

[0002]

2. Description of the Related Art The technology of magnetic particles (also called magnetic beads) has been established as a valuable technology in several fields of biotechnology. According to this technology, various biochemical substances having a selective labeling ability are chemically bonded or attached to the particle surface, and the particles are used in various mixing / reaction steps, whereby the biochemistry of the particle surface is improved. It is possible to obtain a complex reactant that is affinity-bound to the substance, and selectively captures the reaction complex with a magnetic field to remove unnecessary substances (unreacted substance,
Impurities) can be removed.

[0003] One limitation with current technology is one at a time.
Only magnetic separation based on the two components to be detected can be performed, potentially making multiple separations difficult, time consuming and expensive.

For example, Japanese Patent Application Laid-Open No. 2000-516345 discloses that, in order to test different types of components to be detected, magnetic particles having different size ranges that can be distinguished by flow cytometry are prepared. A specific assay reagent is bound to the surface of the particles inside the sample, and the type of assay reagent used is different from that for particles in other size ranges. Has been described.

[0005]

The technique described in Japanese Patent Application Laid-Open No. 2000-516345, which is the prior art described above,
Since the magnetic particle size is limited to a size that can be distinguished by flow cytometry, variations in usable magnetic particles are reduced. Therefore, there is a problem that it is impossible to cope with an increase in the number of types of the substance to be detected.

The present invention has been made in view of the above problems, and utilizes magnetic particles composed of a plurality of materials to individually identify particles even when the types of substances to be detected are extremely large.
It is an object of the present invention to provide a magnetic particle identification device and a magnetic particle identification method that can be separated and can be applied to affinity binding.

[0007]

That is, according to the first aspect of the present invention, there is provided a magnetic particle having a specific magnetic susceptibility, a tube through which the magnetic particle passes, and a magnetic field for generating a magnetic field inside the tube. An apparatus for identifying the magnetic particles by using a generator, an introduction unit for introducing a plurality of magnetic particles having different magnetic susceptibilities into the tube, and applying a magnetic field to the inside of the tube through which the magnetic particles pass to generate a magnetic field. Magnetic field generating means for changing the speed of the particles; and speed detecting means for detecting the speed of the magnetic particles by the magnetic field generating means, wherein the magnetic particles are identified by the change in the speed of the magnetic particles. And

According to a second aspect of the present invention, in the first aspect of the present invention, the introduction means is provided at a position where the magnetic flux density gradient of the magnetic field generated by the magnetic field generation means inside the tube becomes zero. Wherein the magnetic particles are introduced into the tube.

According to a third aspect of the present invention, in the first aspect, the tube is filled with a fluid, and the introduction means introduces the magnetic particles into the tube by the flow of the fluid. It is characterized by doing.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the fluid in the pipe is moved at a constant speed, and the magnetic particles move by the flow of the fluid. Further comprising magnetic particle detecting means for detecting the magnetic particles discharged by the movement of the magnetic particles by applying a magnetic force by the magnetic field generating means, the state in which the particles move at a speed different from the moving speed of the fluid in the tube. Then, the magnetic force generated by the magnetic field generating means is erased, and the magnetic particles are identified based on the time at which the magnetic particles are detected after the magnetic field is erased by the magnetic particle detecting means.

According to a fifth aspect of the present invention, in the first aspect of the invention, the magnetic field generating means generates a magnetic field gradient that is asymmetric with respect to a moving direction of the magnetic particles in the tube. And

According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the magnetic field generating means is constituted by a solenoid coil, and any one of the number of turns of the solenoid coil, the diameter of the solenoid coil, and the coil diameter is used. Is provided so as to increase or decrease with respect to the moving direction of the magnetic particles.

According to a seventh aspect of the present invention, in the first aspect of the invention, the speed detecting means has at least two magnetic particle detectors, and the magnetic particles are composed of the two magnetic particles. The method is characterized in that the speed of the magnetic particles is detected by detecting a difference in time for passing through the detector.

According to an eighth aspect of the present invention, in the seventh aspect of the invention, the magnetic particle detector comprises a light source and a photodetector for receiving light from the light source. The method is characterized in that the magnetic particles are detected by detecting the incidence of light on a photodetector that changes as the light passes.

[0015] The invention according to claim 9 provides the invention according to claim 8.
In the invention described in the above, the light source of the magnetic particle detector is constituted by a laser irradiator that irradiates a laser, the photodetector detects laser reflected light from magnetic particles moving in the tube, The magnetic particle detector further includes a first magnetic head provided between the laser irradiator and the tube in which the magnetic particles move.
And a second half mirror provided between the photodetector and the tube in which the magnetic particles move.

According to a tenth aspect of the present invention, in accordance with the eighth aspect of the present invention, there is further provided an optical fiber for transmitting light from the light source to the magnetic particles in the tube. The optical fiber is provided at a position facing the optical fiber and the tube.

According to an eleventh aspect of the present invention, in the first aspect of the present invention, the speed detecting means includes a conducting wire provided adjacent to the magnetic field generating means in a direction in which the tube extends.
Electromotive force detection means for detecting an electromotive force generated in the conductive wire by the movement of the magnetic particles in the tube, wherein the speed detection means detects the electromotive force of the magnetic particles based on a signal from the electromotive force detection means. It is characterized by detecting a moving speed.

According to a twelfth aspect of the present invention, in the first aspect of the present invention, the velocity detecting means has an imaging means for acquiring an image of the magnetic particles passing through the inside of the tube. The moving speed of the magnetic particles is detected based on the obtained image.

Further, according to the present invention, there is provided a magnetic particle having a different specific magnetic susceptibility and suspended in a liquid which is immiscible with the particle with a bio-related substance fixed on the surface. A reactor for reacting a labeled reagent or biological substance to the magnetic particles, a discrete means connected to the reactor, for discretely dispersing the magnetic particles in a liquid, and a magnetic means connected to the discrete means A tube through which particles pass, a liquid conveying means for feeding the liquid into the tube at a predetermined speed, and a magnetic field generated in the tube, and a magnetic force acting on magnetic particles passing through the tube by the magnetic field,
Magnetic field generating means for changing the moving speed of the magnetic particles moving in the tube, particle identification means for identifying the particles by detecting a change in the speed of the magnetic particles, and the magnetic field generating means for the tube A biological substance reaction detecting means for specifying the affinity binding of the particles to a reagent or a bio-related substance provided downstream of the position provided with, and a signal from the particle identifying means and the biological substance It is characterized in that the affinity binding state on the particle surface corresponding to the identified particle is detected using a signal from the reaction detection means.

According to a fourteenth aspect of the present invention, there is provided a magnetic particle having a different specific magnetic susceptibility and suspended in a liquid which is immiscible with the particle with a bio-related substance fixed on its surface, A reactor for reacting a labeled reagent or a biologically-related substance with respect to a reactor connected to the reactor, discrete means for discretely dispersing the magnetic particles in a liquid, and magnetic particles connected to the discrete means A pipe that passes through the inside, liquid transport means that feeds the liquid into the pipe at a predetermined speed,
A magnetic field generating means for generating a magnetic field in the tube, and changing a moving speed of the magnetic particles moving in the tube by a magnetic force acting on a plurality of types of magnetic particles passing through the tube by the magnetic field; and Provided downstream from the magnetic field generating means, detects magnetic particles that move with the transport of liquid when the magnetic field generated by the magnetic field generating means is erased,
Magnetic particle identification means for individually identifying the magnetic particles from the time from when the magnetic field is erased until the magnetic particles are detected, and the tube provided downstream of the position where the magnetic particle identification means is provided in the tube Biological substance reaction detection means for specifying the affinity binding of the particles to a reagent or a biological substance,
And using the signal from the particle identification means and the signal from the biological substance reaction detection means to detect the affinity binding state of the particle surface corresponding to the identified particle.

The invention according to claim 15 is the invention according to any one of claims 13 and 14, wherein the biological substance reacting with the magnetic particles is labeled with a fluorescent dye. The biological substance reaction detection device is a flow cell, a flow cytometer, or a cell sorter.

The invention according to claim 16 is the invention according to any one of claims 13 and 14, wherein the biological substance immobilized on the surface of the magnetic particles is DNA, R, or R.
NA, a gene, a chromosome, a cell membrane, a virus, a specific binding protein, an antigen, an antibody, a lectin, a hapten, a hormone, a receptor, an enzyme, or a nucleic acid.

According to a seventeenth aspect of the present invention, in accordance with the first aspect of the present invention, the magnetic particles are obtained from a change in the speed of the magnetic particles and a known physical quantity of the magnetic particles. It is characterized by further comprising a magnetic susceptibility detecting means or a particle diameter detecting means for calculating the magnetic susceptibility or the particle diameter.

The invention according to claim 18 is the invention according to any one of claims 4 and 14, wherein the time from when the magnetic field is erased to when the magnetic particles are detected, and It is characterized by further comprising a magnetic susceptibility detecting means or a particle diameter detecting means for calculating a magnetic susceptibility or a particle diameter of the magnetic particle from a known physical quantity.

The invention according to claim 19 is the first or first invention.
The invention according to any one of Items 3 or 14, wherein the magnetic particles include at least one of a ferromagnetic material, a paramagnetic material, a diamagnetic material, and a superconductor.

According to a twentieth aspect of the present invention, magnetic particles having a specific magnetic susceptibility are passed through a tube, a magnetic field is generated inside the tube, and a magnetic force is applied to the magnetic particles. A method for identifying magnetic particles, comprising: introducing a plurality of magnetic particles having different specific magnetic susceptibility into a tube; and applying a magnetic force to the magnetic particles introduced into the tube, A step of changing the speed of the particles; and a step of detecting a change in the speed of the magnetic particles.

According to a twenty-first aspect of the present invention, magnetic particles having a specific magnetic susceptibility are introduced into a tube in which a fluid moves,
A method for identifying a magnetic particle by generating a magnetic field inside the tube and applying a magnetic force to the magnetic particle, wherein a plurality of magnetic particles having different specific magnetic susceptibilities are introduced into the tube by transporting a fluid. Performing a magnetic force on the magnetic particles introduced into the inside of the tube to move the magnetic particles at a speed different from the transport speed of the fluid in the tube, and erasing the magnetic force acting on the magnetic particles And a step of detecting particles that are conveyed downstream of the portion of the tube where the magnetic force acts, and a step of detecting the time from when the magnetic force is erased to when the particles are detected. It is characterized by doing.

According to the invention of claim 22, magnetic particles having a specific magnetic susceptibility are introduced into a tube in which a fluid moves,
A method of identifying the magnetic particles by generating a magnetic field inside the tube and applying a magnetic force to the magnetic particles, wherein the magnetic particles having a different specific magnetic susceptibility and immobilizing a bio-related substance on the surface are used. A step of suspending the magnetic particles and a liquid incompatible with each other, a step of reacting a labeled reagent or a biological substance with respect to the magnetic particles, and a step of separating the magnetic particles from each other in a liquid, Sending a liquid in which discrete magnetic particles are suspended into the inside of the tube at a predetermined speed, generating a magnetic field inside the tube, and applying a magnetic force to the magnetic particles passing through the tube; A step of changing the moving speed of the particles, a step of identifying the magnetic particles by detecting a change in the moving speed of the magnetic particles, and a step of detecting the affinity binding of the magnetic particles with a reagent or a biological substance. ,identification Characterized by comprising the step of detecting the affinity binding reagent or biological substance of the magnetic particles to the magnetic particles, the.

According to a twenty-third aspect of the present invention, magnetic particles having a specific magnetic susceptibility are introduced into a tube in which a fluid moves, and a magnetic field is generated inside the tube to apply a magnetic force to the magnetic particles. Act, a method of identifying the magnetic particles, wherein the magnetic particles having a different specific magnetic susceptibility and immobilized a biological substance on the surface, suspended in a liquid incompatible with the magnetic particles, Reacting a labeled reagent or biologically-related substance with the magnetic particles, separating the magnetic particles from each other in a liquid, and suspending the liquid in which the discrete magnetic particles are suspended within a tube by a predetermined method. Feeding at a speed, generating a magnetic field inside the tube, applying a magnetic force to a plurality of magnetic particles moving in the tube, changing the moving speed of the magnetic particles, acting on the magnetic particles To erase existing magnetic force When the steps of detecting the magnetic particles magnetic force of the tube is conveyed downstream of the part acting,
Detecting the time from erasing the magnetic force until the magnetic particles are detected; identifying the magnetic particles using the detected time; and affinity of the magnetic particles with a reagent or a biological substance. Detecting the affinity of the magnetic particles with the reagent or the bio-related substance with respect to the identified magnetic particles.

According to a twenty-fourth aspect of the present invention, in the fifth aspect, the magnetic field generating means includes an electromagnet.

According to a twenty-fifth aspect of the present invention, in the fifth aspect of the invention, the magnetic field generating means has a permanent magnet.

According to a twenty-sixth aspect of the present invention, in the fifth aspect of the invention, the magnetic field generating means has a superconducting magnet.

According to a twenty-seventh aspect of the present invention, the magnetic field generating means discharges the magnetic particles from the side into which the magnetic particles are introduced. The shape of the pole tip is characterized in that the magnetic flux density is asymmetric and the magnetic flux density in the width direction of the tube becomes uniform toward the side to be cut.

According to the first and twentieth aspects of the present invention,
If there are magnetic particles with different magnetic susceptibility in the tube,
When a magnetic field is generated inside the tube by the magnetic field generator, the speed of the magnetic particles changes due to the magnetic force generated according to the magnetic susceptibility of the magnetic particles. Can be individually identified.

According to the second aspect of the present invention, the magnetic density gradient has a certain gradient from the minus value to the minimum value and from the plus value to the maximum value with a certain gradient centered on the position where the magnetic density gradient becomes zero. When a magnetic field is generated inside the tube by the magnetic field generator,
The magnetic particles accelerate to a position where the product of the magnetic flux density and the magnetic flux density takes a minimum value or a position where the product takes a local maximum value according to its magnetization characteristics, so it is not necessary to apply an external force to the magnetic particles in advance. . Further, if the moving speed V of the magnetic particles is measured at a position where the product of the magnetic flux density and the magnetic flux density gradient shows the minimum or the maximum, it is possible to detect the difference in the magnetic susceptibility of each magnetic particle with the highest sensitivity. . Further, it is possible to identify the magnetic characteristics of a paramagnetic material, a diamagnetic material, and the like, depending on whether the magnetic particles are detected at the minimum or maximum of the magnetic flux density gradient.

According to the third aspect of the invention, the relative speed can be changed according to the magnetic properties of the magnetic particles and the fluid surrounding the magnetic particles. For example, when the magnetic signs of the magnetic particles and the liquid are opposite (one is a diamagnetic material and the other is a paramagnetic material), it is possible to increase the relative velocity difference between the magnetic particles having different magnetic susceptibility. .

According to the fourth and twentieth aspects of the present invention, when magnetic particles having different magnetic susceptibilities are present in a fluid moving at a constant speed inside a tube, a magnetic field is generated according to a signal from a magnetic field control mechanism. When a magnetic field is generated inside the tube by the device, the speed of the magnetic particles is changed by a magnetic force generated according to the magnetic susceptibility of the magnetic particles. Eventually, each magnetic particle stops at a position corresponding to the magnetic susceptibility of the magnetic particle due to the balance of various conditions in the tube, so after sufficiently applying a magnetic force, the magnetic field of the above-described magnetic field generator is reduced by the magnetic field control mechanism. When erased instantaneously, each magnetic particle moves in the tube at the fluid velocity v ₀ while maintaining the separated mutual relationship,
By detecting the time from when the magnetic field is erased to when each magnetic particle is detected, the magnetic particles can be individually identified.

According to the fifth aspect of the present invention, since the magnetic flux density of the magnetic field generator is configured to be asymmetric from the side where the magnetic particles are introduced to the side where the magnetic particles are discharged, the maximum value of the product of the magnetic flux density and the magnetic flux density gradient is obtained. Alternatively, the minimum value and the magnetic force generated at the maximum value or the minimum value point can be increased.

According to the sixth aspect of the present invention, in the solenoid coil, the number of coil turns, the solenoid diameter, and the coil diameter monotonically increase or decrease from the side where the magnetic particles are introduced to the side where the magnetic particles are discharged. The magnetic flux density is asymmetrical, and the magnetic force can be increased and the difference in magnetic susceptibility of the magnetic particles is most effective at the maximum or minimum value of the product of the magnetic flux and the magnetic flux density gradient. Can be taken out.

According to the seventh aspect of the present invention, the magnetic particles are detected by two or more magnetic particle detectors arranged along the pipe, and then the velocity detector connected to the magnetic particle detector is used. The moving speed of the magnetic particles can be calculated from the signal detection time difference at the installation position of each magnetic particle detector.

According to the eighth aspect of the present invention, since the passage of the magnetic particles is detected by light, the response responsiveness is excellent.

According to the ninth aspect of the present invention, since the light path is divided by the half mirror, only one light source and one detection system are required, and the laser irradiator irradiates the magnetic particles with light.
Since the passage of magnetic particles is detected by the reflected light, the directivity is excellent and the detection of microspheres is excellent.

According to the tenth aspect of the present invention, since the light irradiated by the optical fiber is detected by the photodetector provided at the opposite electrode, it is possible to detect that the light is blocked by the passage of the magnetic particles. By detecting, the magnetic particles can be detected.

According to the eleventh aspect of the present invention, the electromotive force is generated in the conductor provided near the magnetic field generator by the movement of the magnetic particles inside the tube where the magnetic field is acting. The velocity of the magnetic particles can be detected by measuring the electromotive force of the conducting wire by the connected electromotive force detection means.

According to the twelfth aspect of the present invention, since the image of the magnetic particles is acquired by the imaging means and the movement of the magnetic particles is detected from this image, the image is analyzed to thereby analyze the magnetic particles. The moving speed can be detected.

According to the thirteenth and twenty-second aspects of the present invention, the immobilization of a biological substance suspended in an incompatible liquid in a state where a specific biological substance is fixed on the surface of the magnetic particles. The magnetic particles are mixed and reacted with a reagent or a biological substance for reaction in a reactor. After the reaction, the biological material-immobilized magnetic particles are individually dispersed in the liquid by the liquid transport mechanism, and are transported together with the liquid at a predetermined speed. For the magnetic particles, the change in velocity and the result of affinity binding due to the mixing and reaction of the biological material-immobilized magnetic particles are measured in each of the particle property detector and the biological substance reaction detector provided at the destination. The biological substance detection system incorporates a reaction result display that displays the results of affinity binding on the surface of each identified particle by combining the results of the particle property detector and the biological substance reaction detector. Because
By identifying individual magnetic particles, it is possible to individually detect which biological substance has reacted with which reagent or reaction biological substance while identifying the type of biological substance on the surface of each magnetic particle. It becomes possible.

Further, according to the invention of claim 14 and claim 23, the immobilization of the biological material suspended in the incompatible liquid in a state where the specific biological material is fixed on the surface of the magnetic particles. The magnetic particles are mixed and reacted with a reagent or a biological substance for reaction in a reactor. After the reaction, the biological material-immobilized magnetic particles are individually dispersed in the liquid by the liquid transport mechanism, and are transported together with the liquid at a predetermined speed. The time difference from the elimination of the magnetic field to the detection of each magnetic particle and the mixing / reaction of the biological material-immobilized magnetic particles in each of the particle characteristic detector and biological material reaction detector provided at the transport destination Affinity binding results are measured.
The biological substance detection system incorporates a reaction result display that displays the results of affinity binding on the surface of each identified particle by combining the results of the particle property detector and the biological substance reaction detector. Therefore, by identifying individual magnetic particles, it is possible to individually identify the type of biological substance on the surface of each magnetic particle and individually identify which biological substance has reacted with which reagent or biological substance for reaction. It becomes possible to detect.

According to the fifteenth aspect of the present invention, a biological substance reaction detector such as a flow cell, a flow cytometer, or a cell sorter is used for moving a substance to be measured by a fluid while the biological substance for reaction is labeled with a fluorescent dye. Since the affinity binding result can be measured by detecting the fluorescent emission site of the substance, the affinity binding result can be obtained in a short time.

According to the sixteenth aspect of the present invention, a biologically relevant substance immobilized on the surface of the magnetic particles is not limited, so that a highly customizable experiment can be performed.

According to the seventeenth aspect, since the moving speed of the magnetic particles changes according to the magnetic susceptibility of the magnetic particles, when the peripheral magnetic susceptibility, the magnetic flux density, the magnetic flux density gradient and the like are known in advance, If the moving speed calculated by the speed detector following the particle characteristic detector is known, the magnetic susceptibility or the particle diameter of the magnetic particles can be calculated by the magnetic susceptibility measuring device.

According to the eighteenth aspect of the present invention, after sufficiently applying a magnetic force, the magnetic particles are stopped at a position in the tube corresponding to the magnetic susceptibility by balancing the external magnetic field and other conditions. Here, if the magnetic field of the magnetic field generator is erased in a short period of time by the magnetic field control mechanism, the magnetic particles move in the tube at the fluid velocity v ₀ while maintaining the separated mutual positional relationship. Since the time from when the magnetic particles are detected changes according to the magnetic susceptibility of each magnetic particle, when the peripheral magnetic susceptibility, magnetic flux density, magnetic flux density gradient, etc. are known in advance, each magnetic particle is erased from the magnetic field erasure. If the time difference until is detected, the magnetic susceptibility or particle diameter of the magnetic particles can be calculated by the magnetic susceptibility measuring device.

According to the nineteenth aspect of the present invention, since magnetic particles are produced from various types of materials, a very large number of types of particles having different magnetic susceptibility χ can be prepared and used for individual identification. The number of particles that can be formed can be increased.

According to the twenty-fourth aspect of the present invention,
By adjusting the shape of the electromagnet and the value of the current flowing through the electromagnet, the magnetic flux density distribution in the tube through which the magnetic particles flow can be set to an arbitrary value.

According to the twenty-fifth aspect, a stable magnetic field can be generated for a long period of time by the permanent magnet, and a stable magnetic flux density distribution can be created in the tube.

According to the twenty-sixth aspect, a small and strong magnetic field can be generated by the superconducting magnet, so that the magnetic particle identification device can be downsized.

Further, according to the invention of claim 27,
Since the magnetic flux density in the width direction of the tube is uniform, the speed change of the magnetic particles becomes the same regardless of the portion where the magnetic particles pass through the tube, and accurate detection of the particles can be performed.

[0057]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a basic configuration of a first embodiment of the magnetic particle identification apparatus of the present invention.

In FIG. 1, the tube 1 is filled with an incompatible liquid. An introduction mechanism 3 for introducing magnetic particles 2 having a specific magnetic susceptibility into the tube is connected to the tube 1. A solenoid coil 4 is provided outside the tube 1. The solenoid coil 4 serves as a magnetic field generator for artificially generating a magnetic field for the magnetic particles 2 inside the tube 1, and has a monotonically increasing number of coil turns from the side where magnetic particles are introduced to the side where magnetic particles are discharged. Are arranged on the circumference so as to increase. Further, two magnetic particle detectors 6 and 7 are provided at both ends of the solenoid coil 4 on the side surface along the tube 1.

The magnetic particle detector 6 is provided on the upstream side outside the magnetic particle introduction port of the solenoid coil 4, while the magnetic particle detector 7 is provided on the downstream side outside the magnetic particle discharge port of the solenoid coil 4. It is provided in. Further, the speed detector 8 detects the magnetic particle based on the time difference between the detection signals of the magnetic particles 2 at the installation positions of the magnetic particle detectors 6 and 7 and the known installation distance of the two magnetic particle detectors. Calculate the speed of The magnetic particle detectors 6 and 7 and the velocity detector 8 constitute a particle characteristic detector 10.

A magnetic susceptibility measuring device 11 is connected to the particle characteristic detector 10. This susceptibility measuring instrument 11
The magnetic susceptibility of the magnetic particles is calculated based on the known physical quantity and the detected speed of the magnetic particles.

FIG. 2 is a diagram specifically showing the configuration of the magnetic particle identification device according to the first embodiment of the present invention.

The pipe 15 which is a flow path having a predetermined diameter is filled with an incompatible liquid. An introduction mechanism 17 for introducing magnetic particles 16 having a specific magnetic susceptibility into the tube 15 is connected to the inside of the tube 15.

The magnetic particles 16 have a size of several μm to several hundred μm.
It has an average particle size and is made of a diamagnetic substance. The introduction mechanism 17 is arranged such that the magnetic particles 16 are introduced into the center of the tube 15. Introduction mechanism 1
The cross-sectional shape and cross-sectional area of the tube 7 and the tube 15 can be arbitrarily set as long as the liquid and the magnetic particles 16 can sufficiently flow. Now, the tube 15 is made of a transparent material.
Has a circular cross section and a diameter of several tens to several mm.

The pipe 15 is provided with a liquid transport mechanism 18 for moving the fluid inside the pipe at a predetermined speed. Also,
A solenoid coil 19 is provided outside the tube 1 so that the number of coil turns monotonically increases from the side where magnetic particles are introduced to the side where magnetic particles are discharged. The solenoid coil 19 is connected to a magnetic field control mechanism 26 for controlling the magnetic field strength, the generation of the magnetic field, and the elimination of the magnetic field.

Further, a particle property detector 21 for individually identifying the magnetic particles 16 by detecting a change in the speed of the magnetic particles 16 is provided outside the tube 15. The particle property detector 21 includes two magnetic particle detectors 22 and 23.
And a speed detector 24. Further, a magnetic susceptibility measuring device 25 is connected to the speed detector 24.

The above-mentioned magnetic particle detectors 22 and 23 correspond to FIG.
As shown in FIG. 3, a laser irradiator 28 for irradiating the magnetic particles 16 with a laser, the laser irradiator 28 and the magnetic particles 1
Half mirror 2 provided between tube 6 and movable tube 15
9a, a photodetector 30 for detecting laser reflected light from the magnetic particles 16, and a half mirror 29b provided between the photodetector 30 and a moving path of the magnetic particles 16.

Next, the operation of the first embodiment of the present invention will be described.

The inside of the tube 15 is filled with an incompatible liquid, and the liquid inside the tube 15 is moved by the liquid transfer mechanism 18 at a predetermined speed in the direction of the arrow shown in the figure. Although not shown, a particle isolation mechanism is provided upstream of the introduction mechanism 17 for isolating the magnetic particles in the liquid (from an aggregated state to a state of being individually dispersed and moving individually). Therefore, the magnetic particles 16 are introduced into the tube 15 from the introduction mechanism 17 in an individually isolated state. After the introduction, each magnetic particle 16 moves in a state where the inside of the tube 15 is isolated, but the magnetic particle 16 flows at the same speed as the liquid when there is no influence of the external magnetic field.

Now, consider the case where the magnetic field control mechanism 26 causes the solenoid coil 19 to generate a magnetic field of a predetermined strength.

The solenoid coil 19 according to the present invention comprises:
As shown in FIG. 4A, the number of coil turns is monotonically increased from the side where magnetic particles are introduced to the side where magnetic particles are discharged. The number of coil turns per unit length is defined by the following equation (1).

N _mks = c _nst x + n ₀ (1) where c _nst > 0. X is the length of the coil, n
₀ is the number of coil turns per unit length at the start of winding.

When the radius of the solenoid coil 19 is a and the length is b, the magnetic flux density by the solenoid coil 19 is given by the following equation (2).

[0074]

(Equation 1)

According to the above equation (2), when the number of coil turns changes, the magnetic flux density changes. Therefore, as shown in FIG. 4B, the pipe 15 extends from the side where the magnetic particles 16 are introduced to the side where the magnetic particles 16 are discharged. The magnetic flux density inside is asymmetric. Further, the magnetic flux density gradient with respect to the moving direction of the liquid has a minimum value at the outlet having the largest number of coil turns, as shown in FIG.

The liquid immiscible with the magnetic fluid filled in the pipe 15 is moving inside the pipe 15 at a predetermined speed v ₀ by the liquid transport mechanism 18. When a magnetic field is generated in the solenoid coil 19 with a predetermined magnetic field intensity by the magnetic field control mechanism 26, the magnetic particles 16 inside the tube 15 generate a magnetomotive force F due to the magnetic field.
_m occurs.

[0077]

(Equation 2)

[0078] Here, chi _l is the magnetic susceptibility of the magnetic particles, chi _m is the magnetic susceptibility of the liquid, mu ₀ is the vacuum magnetic permeability, r is a magnetic particle radius,
B is the magnetic flux density, and dB / dx is the magnetic flux density gradient with respect to the moving direction of the liquid. Meanwhile, when the magnetic particles 16 by the magnetomotive force is moved at a relative speed v relative to the liquid, viscous force F _v of the fluid becomes _{F v = 6πrηv ... (4)} . Here, r is the magnetic particle radius, and η is the liquid viscosity. It is assumed that the moving speed v _{0 of the} liquid is sufficiently higher than the relative speed v.

[0079] When the magnetic particles 16 by the magnetomotive force moves, F _v = F _m ... relationship (5) is satisfied. At this time, the relative velocity v of the magnetic particles 16 is

(Equation 3) It can be seen that the magnitude of the relative velocity v is determined by the magnetic susceptibility χ _l , χ _m of the magnetic particles 16 and the liquid, the magnetic flux density, the magnitude of the magnetic flux density gradient, and the magnetic particle size.

As described above, the solenoid coil 19 according to the present invention is configured so that the number of coil turns monotonically increases from the side where magnetic particles are introduced to the side where magnetic particles are discharged, so that the magnetic flux density is increased. The effect of the magnetic flux density gradient is greatest at the magnetic particle outlet of the solenoid coil 19. Therefore, if the relative velocity v is measured at this position, the difference in the magnetic susceptibility of each magnetic particle can be detected with the highest sensitivity. That is, individual magnetic particles can be identified with the highest sensitivity.

Now, when the magnetic particle size is constant, each absolute value of the magnetic susceptibility χ ₁ , χ ₂ , χ ₃ and the magnetic susceptibility χ _m of the liquid is determined by the following equation: | χ _m | <| χ ₁ When | <| χ ₂ | <| χ ₃ | (7), the relative velocity of the magnetic particles with respect to the magnetic susceptibility of the magnetic particles and the liquid has a relationship as shown in FIG. In each graph, the horizontal axis represents the distance in the moving direction of the liquid, and the vertical axis represents the relative velocity v.

The magnetic particles of the present embodiment are made of a diamagnetic substance and have a specific magnetic susceptibility. If the liquid in which the magnetic particles are suspended is a diamagnetic substance, the relative velocity v distribution as shown in FIG.

On the other hand, FIG. 5B shows the results for the case of paramagnetic particles / diamagnetic liquid, FIG. 5C shows the results for the case of diamagnetic particles / paramagnetic liquid, and FIG. Is paramagnetic particles /
The results for the paramagnetic liquid are shown respectively. The relative velocity changes more when the magnetic sign of the magnetic particles 16 and the liquid is opposite (one is a diamagnetic substance and the other is a paramagnetic substance), or as the magnetic susceptibility of the magnetic particles 16 increases. Is shown.

Further, considering these results and the graph of FIG. 4, in the case of the diamagnetic particles, the relative velocity v of the magnetic particles with respect to the liquid becomes maximum at the position where the magnetic flux density gradient takes the minimum value. Then, it moves inside the pipe 15 faster (in an accelerated state) than the liquid moving speed. Conversely, in the case of paramagnetic particles, the relative velocity v of the magnetic particles to the liquid is minimized at the position where the magnetic flux density gradient has a minimum value. The relative velocity v of the particles 16 to the liquid is reduced.

In the case of paramagnetic particles and diamagnetic particles,
FIG. 6 shows an example of the detection time in the magnetic particle detectors 22 and 23. Therefore, the magnetic particle detector 22 provided outside and upstream of the magnetic particle introduction port of the solenoid coil 19 according to the present invention, and the magnetic particle detector 22 provided outside and downstream of the magnetic discharge port of the solenoid coil where the magnetic flux density gradient becomes maximum. The passage of particles is detected by the particle detector 23. Since the installation distance of these two magnetic particle detectors 22 and 23 is known, the speed detector detects the magnetic field based on the time difference between the detection signals of the magnetic particles 16 at the installation positions of the magnetic particle detectors 22 and 23. The relative velocity v of the particles is determined.

By modifying the above equation (6), the magnetic susceptibility χ _l of the magnetic particles 16 becomes

(Equation 4) Therefore, the measured relative velocity v of the magnetic particles 16 and the liquid magnetic susceptibility χ _m , magnetic particle radius r, liquid viscosity η, magnetic flux density B, and magnetic flux density gradient dB / dx are given in advance. if, it is possible to calculate the magnetic susceptibility chi _l of the magnetic particles. That is, if the above equation (8) is defined in the susceptibility measuring device 25, the output signal from the speed detector 24 is received and the relative speed v of the magnetic particles 16 is given. , The magnetic susceptibility 磁 気_l of the magnetic particles 16
Can be calculated.

Further, according to the present invention, the above magnetic particles 1
By applying the principle of the magnetic susceptibility measuring method in No. 6, it is also possible to measure the particle diameter of magnetic particles whose magnetic susceptibility is known and whose particle diameter is unknown. In the measurement of the particle size of the magnetic particles, the above-described magnetic particle identification apparatus and method are performed on magnetic particles having a known magnetic susceptibility and an unknown particle size, and the relative velocity of the magnetic particles with respect to the liquid is measured. Calculate v.

If the relative velocity v of the magnetic particles can be measured, and the magnetic susceptibility χ _l of the magnetic particles, the liquid susceptibility χ _m , the liquid viscosity η, the magnetic flux density B, and the magnetic flux density gradient dB / dx are known, the above (8) By transforming the expression,

(Equation 5) The magnetic particle radius r is calculated.

That is, as shown in FIG. 7, a particle size measuring device 32 for calculating the particle size of magnetic particles is provided in place of the magnetic susceptibility measuring device 25, and the particle size measuring device 32 is provided with the above (9). If the equation is defined, the particle diameter measuring device 32 can calculate the particle radius r of the magnetic particles by receiving the output signal from the speed detector 24 and giving the relative speed v of the magnetic particles 16. It is.

Incidentally, each constitution of the embodiment of the present invention can of course be variously modified and changed. For example, the magnetic particles to be measured may be, in addition to a diamagnetic substance, a single or a plurality of superconductors including a ferromagnetic substance, a paramagnetic substance, an antiferromagnetic substance, a diamagnetic substance or a high temperature superconductor. It can be composed of a solid or a superconductor material, and the incompatible liquid may be a paramagnetic substance or a diamagnetic substance.

What fills the inside of the flow path may be gas or vacuum other than liquid.

Further, the solenoid coil 19 may be configured so that the product of the magnetic flux density and the magnetic flux density gradient is asymmetric. For example, from the side where the magnetic particles are introduced to the side where they are discharged, the solenoid diameter is configured to decrease,
It may be configured such that the coil diameter is reduced. Conversely, the solenoid coil 19 is configured such that the number of turns decreases from the side where the magnetic particles are introduced to the side where the magnetic particles are discharged, the solenoid coil 19 is configured so that the solenoid diameter increases, or the coil diameter increases. May be increased. In addition to the solenoid coil, a permanent magnet or the like may be applied to the magnetic field generator.

The magnetic particle detectors 22 and 23 may be composed of an optical fiber for irradiating the magnetic particles 16 with light, and a photodetector installed at the opposite electrode of the optical fiber for detecting light. .

On the other hand, a biological substance such as DNA may be fixed on the surface of the magnetic particles. In this case, the biologically relevant substances include, for example, RNA, gene, chromosome, cell membrane, virus, specific binding protein, antigen, antibody, lectin, hapten, hormone, receptor, enzyme,
It may be a nucleic acid or the like.

Further, as a means for measuring the affinity binding of such a biological substance, a flow cytometer, a flow cell, a cell sorter or the like is connected downstream of the tube 15, and the magnetic susceptibility の and the particle size of the magnetic particles 16 determine the magnetic susceptibility. The configuration may be such that by identifying and separating particles, the type of DNA on the surface of each magnetic particle can be specified, and which DNA has reacted with which reagent DNA can be individually detected.

Further, a magnetic particle extraction mechanism that can extract necessary particles depending on the type of the identified magnetic particles 16 may be provided downstream of the tube 15.

Next, a second embodiment of the present invention will be described.

FIG. 8 is a diagram showing a configuration of a magnetic particle identification device according to the second embodiment of the present invention.

In the embodiments described below, the same parts as those in the above-described embodiments are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 8, along the outer peripheral surface of the pipe 15,
As shown in FIG. 4A, as a magnetic field generator for artificially generating a magnetic field with respect to magnetic particles inside a tube, as shown in FIG. Is provided with a solenoid coil 19 having a large number of coil turns. A particle characteristic detector 35 is provided on the downstream side of the solenoid coil 19 near the magnetic particle discharge port.

The particle characteristic detector 35 is provided for the magnetic particles 16.
The magnetic particles are individually identified by detecting the speed change of the magnetic particles. The particle characteristic detector 35 includes an annular conductor 36, an electromotive force detector 37 that follows the annular conductor 36, and detects a change in induced electromotive force generated by the movement of the magnetic particles 16; The speed detector 24 is connected to the electromotive force detector 37 and calculates the speed of the magnetic particles 16 from the detection signal pattern of the electromotive force detector 37.

Further, a magnetic susceptibility measuring device 25 is connected to the velocity detector 24 in the particle characteristic detector 35. Further, a magnetic field control mechanism 26 for generating a magnetic field in the solenoid coil 19 with a predetermined magnetic field strength is connected to the solenoid coil 19. By the magnetic field control mechanism 26, the magnetic field strength,
Magnetic field generation and magnetic field extinction are controlled.

The magnetic particles 16 have a particle size of several μm to several hundred μm and are made of a diamagnetic substance. The tube 15 is filled with an incompatible liquid. The tube 15 contains a liquid transport mechanism 18 for transporting the internal liquid at a predetermined speed v ₀ and magnetic particles 16 having a specific magnetic susceptibility. 15 is connected to an introduction mechanism 17 for introduction into the inside. The introduction mechanism is arranged such that the magnetic particles are introduced into the central portion of the tube.

The cross-sectional shape and cross-sectional area of the introduction mechanism 17 and the tube 15 can be arbitrarily set as long as the liquid and the magnetic particles 16 can sufficiently flow. Although not shown, there is a particle isolation mechanism on the upstream side of the introduction mechanism 17 for isolating magnetic particles in the liquid. 15 is introduced inside. Each of the magnetic particles 16 after the introduction moves in a state where the inside of the tube 15 is isolated. However, since the liquid in the tube 15 is moving at a predetermined speed by the liquid transport mechanism 18, the magnetic particles 16 are moved by the external magnetic field. flowing at the same speed v ₀ with the liquid when there is no impact.

Now, consider the case where the solenoid coil generates a magnetic field of a predetermined strength by the magnetic field control mechanism.

When the magnetic flux density of the solenoid coil 19 is given by the above equation (2), the magnetic particles 16 inside the tube 15
Has a magnetic force F _m defined by the above equation (3) due to a magnetic field.
Occurs. Meanwhile, when the magnetic particles by magnetic force to move at a relative speed v relative to the liquid, because the viscous force F _v of the fluid becomes Equation (4), when the magnetic particles are moved by magnetic force, the formula (5) The relationship is established. At this time, the relative velocity v of the magnetic particles 16 becomes as in the above equation (6),
The magnitude of the relative velocity v depends on the magnetic susceptibility χ _l of the magnetic particles and the liquid,
and chi _m, the magnetic flux density, the magnitude of the magnetic flux density gradient, it can be seen that determined by the magnetic particle size.

The solenoid coil 19 of the present invention is configured so that the number of coil turns monotonically increases from the side where magnetic particles are introduced to the side where magnetic particles are discharged. Is largest at the magnetic particle outlet of the solenoid coil 19. Therefore, if the relative velocity v is measured at this position, the difference in the magnetic susceptibility of each magnetic particle can be detected with the highest sensitivity.

For example, in the case of diamagnetic particles, the relative velocity v of the magnetic particles with respect to the liquid becomes maximum at the position where the magnetic flux density gradient takes the minimum value, and is faster than the liquid moving speed (in an accelerated state). It moves inside the pipe 15. Conversely, in the case of paramagnetic particles, the relative velocity v of the magnetic particles to the liquid is minimized at the position where the magnetic flux density gradient has a minimum value. Relative to the liquid is reduced. That is, it is possible to identify the individual magnetic particles 16 with the highest sensitivity in the vicinity of the magnetic particle outlet of the solenoid coil 19.

Therefore, in the second embodiment, a particle characteristic detector for individually identifying the magnetic particles by detecting a change in the speed of the magnetic particles is provided outside and downstream of the solenoid coil near the magnetic particle discharge port. Have been.

FIG. 9 shows an example of a detection signal pattern in the electromotive force detector 37 when three magnetic particles are sequentially discharged from the magnetic particle discharge port of the solenoid coil 19.

If the distance when the maximum value P of the electromotive force indicates an inverse value is known, the velocity v of the magnetic particles can be calculated by detecting the time t of the inverse value width of the maximum value P.

[0112] Incidentally, the above (8), since the magnetic susceptibility chi _l of the magnetic particles 16 is applied, and the relative velocity v of the measured magnetic particles 16, the magnetic susceptibility chi _m pre liquids, magnetic particle radius r , fluid viscosity eta, magnetic flux density B, if given magnetic flux density gradient dB / dx is, it is possible to calculate the magnetic susceptibility chi _m of the magnetic particles 16.

That is, as shown in FIG. 8, a magnetic susceptibility measuring device 25 is provided after the particle characteristic detector 35, and if the magnetic susceptibility measuring device 25 is defined by the above equation (8), receives an output signal from the speed detector 24, by the relative velocity v of the magnetic particles 16 is applied, magnetic susceptibility meter 25 is able to calculate the magnetic susceptibility chi _l of the magnetic particles 16.

In the present embodiment, the speed of the magnetic particles is detected by detecting the induced electromotive force accompanying the movement of the magnetic particles. However, instead of the electromotive force detector, an image of the magnetic particles flowing in the tube is taken. An imaging unit may be provided, and a moving speed of the magnetic particles may be obtained from a temporal change of an image of the magnetic particles captured by the imaging unit.

Further, in the present invention, by utilizing the above equation (9), the principle of the method for measuring the magnetic susceptibility of the magnetic particles is applied, and the magnetic susceptibility is known and the particle diameter is unknown. Measurement of the particle size of the magnetic particles can be performed.

That is, the susceptibility measuring device 25 shown in FIG.
In place of the above, a particle size measuring device for calculating the particle size of the magnetic particles is provided, and if the above-mentioned expression (9) is defined in this particle size measuring device, the output signal from the speed detector 24 is received, Given the relative velocity v, the particle size measuring device can calculate the particle radius r of the magnetic particles.

It is to be noted that each configuration of the above-described second embodiment can of course be variously modified and changed. For example, magnetic particles include, in addition to diamagnetic substances, one or more magnetic substances or superconducting substances, including ferromagnetic substances, paramagnetic substances, antiferromagnetic substances, diamagnetic substances, and superconductors including high-temperature superconductors. The immiscible liquid may be a paramagnetic substance or a diamagnetic substance.

[0118] What fills the inside of the flow path may be gas or vacuum other than liquid.

Further, the solenoid coil may be configured so that the product of the magnetic flux density and the magnetic flux density gradient is asymmetric. For example, it may be configured such that the solenoid diameter decreases from the side where the magnetic particles are introduced to the side where the magnetic particles are discharged, or that the coil diameter decreases. vice versa,
The solenoid coil is configured so that the number of turns decreases in a decreasing manner from the side where the magnetic particles are introduced to the side where the magnetic particles are discharged, or the solenoid diameter is configured to be increased, or the coil diameter is configured to be increased. May be used. In addition, the magnetic field generator may be constituted by permanent magnets or the like other than the solenoid coil.

Further, the electromotive force detector in the speed detector may be configured by an ammeter for detecting a change in induced current or a voltmeter for detecting a change in induced electromotive force. On the other hand, a bio-related substance such as DNA may be fixed on the surface of the magnetic particles. Examples of the bio-related substance include RNA, gene, chromosome, cell membrane, virus, specific binding protein, antigen, and antibody. , Lectins, haptens, hormones, receptors, enzymes, nucleic acids and the like.

Further, as means for measuring the affinity binding of such a biological substance, a flow cytometer, a flow cell, a cell sorter or the like is connected to the downstream side of the tube, and the magnetic particles are determined by the magnetic susceptibility χ and the particle size. By identifying and separating,
While identifying the DNA type on each magnetic particle surface,
The configuration may be such that it is possible to individually detect which reagent DNA NA has reacted with.

Further, a magnetic particle extracting mechanism that can extract necessary particles depending on the type of the identified magnetic particles may be provided on the downstream side of the tube.

Next, a third embodiment of the present invention will be described.

FIG. 10 is a diagram showing a configuration of a magnetic particle identification device according to the third embodiment of the present invention.

The magnetic particles according to the third embodiment have a particle size of about several μm to several hundred μm, and are composed of a diamagnetic substance, a ferromagnetic substance, a paramagnetic substance, an antiferromagnetic substance, Of the superconductors, including magnetic or high-temperature superconductors, because they are composed of one or more magnetic or superconductor materials,
Each magnetic particle has a specific magnetic susceptibility. In addition, these magnetic particles are a predetermined type of DN
A is fixed to the surface of each particle, and is filled in a tube in a state of being suspended in an incompatible reagent solution.

In the reagent solution, a plurality of DNAs complementary to the DNA immobilized on the surface of the magnetic particles are present.
By affinity binding, only DNAs that are complementary to each other specifically bind to DNA on the magnetic particles. That is, in the present embodiment, the individual magnetic particles are set so that individual affinity binding occurs on each surface. The DNA in the reagent solution is modified with a fluorescent dye. Therefore, by exciting this dye at a specific wavelength and measuring the fluorescence, it is possible to detect whether or not affinity binding has occurred on the surface of the magnetic particles.

In the third embodiment, the tube also serves as a reactor for mixing and reacting a plurality of magnetic particles with a reagent solution.

This tube 15 is connected to a flow cytometer 40 for detecting affinity binding of DNA at a position downstream of the magnetic particle outlet of the solenoid coil 19. Further, the cross-sectional shape and cross-sectional area of the tube 15 can be arbitrarily set within a range in which the liquid and the magnetic particles 41 can sufficiently flow, but now, the tube 15 is made of a transparent material, and the cross-sectional shape of the tube 15 is It is annular and the pipe diameter is several tens to several mm. The pipe 15 is provided with a liquid transport mechanism 18 for moving the fluid inside the pipe 15 at a predetermined speed.

On the other hand, on the outside of the tube 15, a magnetic field generator for artificially generating a magnetic field for the magnetic particles 41 inside the tube 15 is provided on the side from which the magnetic particles 41 are introduced to where the magnetic particles are discharged. , The solenoid coil 1 configured on the circumference so as to monotonically increase the number of coil turns
9 are provided. The solenoid coil 19 has a magnetic field control mechanism 2 for controlling magnetic field strength, magnetic field generation, and magnetic field extinction.
6 is connected.

A particle characteristic detector 42 for identifying the magnetic particles 41 by detecting the behavior of the magnetic particles 41 is provided on the downstream side of the side on which the magnetic particles in the tube 15 are discharged to the outside of the solenoid coil. ing. This particle property detector 42
Is composed of a magnetic particle detector 43, a movement time detector 44, and a susceptibility measuring device 25.

The magnetic particle detector 43 is disposed one downstream of the magnetic particle discharge port of the solenoid coil 19. In the solenoid coil 19, based on the moving time difference of the magnetic particles from the moment when the magnetic field control mechanism 26 that has generated the magnetic field erases the magnetic field to the time when it passes through the magnetic particle detector,
It comprises a moving time detector 44 for estimating and calculating the capturing position of the magnetic particles, and a susceptibility measuring device 25 for receiving the signal from the moving time detector 44 and calculating the magnetic susceptibility of the magnetic particles.

Although not shown, the magnetic particle detector 43 includes an optical fiber for irradiating the magnetic particles with light, and a photodetector provided at the opposite electrode of the optical fiber for detecting light.

Next, the operation of the third embodiment will be described.

The magnetic particles 41 are filled in the pipe 15 in a state of being suspended in an incompatible liquid, and the liquid transport mechanism 18
As a result, the liquid inside the tube 15 moves at a predetermined speed in the direction of the arrow shown in the figure. The magnetic particles 41 may, when there is no influence of an external magnetic field, flowing at the same velocity v ₀ with the liquid.

Now, when the solenoid coil 19 generates a magnetic field of a predetermined strength by the magnetic field control mechanism 26, FIG.
As shown in (b), the magnetic flux density in the tube 15 becomes asymmetric from the side where the magnetic particles 41 are introduced to the side where they are discharged. Also, the magnetic flux density gradient with respect to the moving direction of the liquid is
As shown in FIG. 4C, the minimum value is obtained at the outlet having the largest number of coil turns.

When a magnetic field is generated in the solenoid coil 19 with a predetermined magnetic field intensity by the magnetic field control mechanism 26 and the magnetic particles 41 move at a relative velocity v with respect to the liquid due to the magnetic force, the magnetic particles 41 inside the tube 15 are subjected to a magnetic field. Magnetic force F
The viscous force F _v of _m and the fluid, the equation (5) in relation holds. At this time, the relative velocity v of the magnetic particles is determined by the magnetic susceptibility χ _l , χ _m of the magnetic particles and the liquid, the magnetic flux density, and the magnitude of the magnetic flux density gradient.

Now, it is assumed that the moving speed v _{0 of the} liquid is substantially equal to the relative speed v. In that case, if a predetermined magnetic field is continuously generated in the solenoid coil 19 as it is,
The magnetic particles 41 with to move through the tube 15, at the point where the relative velocity v of the magnetic particles 41 is balanced with the liquid moving speed v _0, so absolute velocity is captured becomes zero.

For example, in the case of diamagnetic particles, the relative velocity V of the magnetic particles with respect to the liquid becomes maximum at a position where the magnetic flux density gradient takes a minimum value, and is faster than the liquid moving speed (in an accelerated state). Moving in the pipe 15, the speed is gradually reduced in accordance with the magnetic flux density gradient, and stops at a point where the liquid moving velocity v ₀ is balanced.

Conversely, in the case of paramagnetic particles, the relative velocity V of the magnetic particles with respect to the liquid is minimized at the position where the magnetic flux density gradient has a minimum value, so that the position approaches the position where the magnetic flux density gradient has a minimum value. , And comes to a standstill at a point where it is balanced with the liquid moving speed v ₀ . That is, as shown in FIG. 10, a plurality of magnetic particles 41 can be separated in the tube 15 according to the magnetic susceptibility.

Next, after the magnetic particles 41 are separated from each other in position, the magnetic field generated in the solenoid coil 19 by the magnetic field control mechanism 26 is instantaneously erased. while maintaining the positional relationship, moves the tube 15. in the moving velocity v ₀ of the reagent solution.

FIG. 11 shows an example.

When the magnetic field of the solenoid coil 19 is eliminated, each magnetic particle 41 maintains a certain positional relationship (L _{1 to} L ₅ ) according to the relative velocity v so far.
It moves inside the tube 15 at the moving speed v ₀ of the reagent solution. At the moment when the magnetic field is erased, t = 0, the magnetic particles 41a at that time
And the distance between the magnetic particle detector 43 and L _0. Similarly,
The distance between the magnetic particles 41a and 41b is L ₁ , the distance between the magnetic particles 41b and 41c is L ₂ , the distance between the magnetic particles 41c and 41d is L ₃ ,
The distance between d and the magnetic particles 41e L _4, the distance between the magnetic particles 41e and the magnetic particles 41f and L _5. The distance the L _x from the outlet of the solenoid coil 19 to the magnetic particle detector 43, the radius of the solenoid coil 19 a, the length b
And

Now, as shown in FIG. 12, a time t _n (n = 1, 2,...) From the moment when the magnetic particles 41a to 41f are detected by the magnetic particle detector 43 until the magnetic particles 41a to 41f are detected.
If 6) is measured, the positional relationship on the x-axis of the n-th magnetic particle detected by the magnetic particle detector 43 can be defined as follows.

[0144]

(Equation 6)

The above equation (10) indicates that the solenoid coil 19
Corresponds to the capturing position of the magnetic particles when a predetermined magnetic field was generated. If it is possible to estimate the catching position x = X _l of the magnetic particles, (2) the magnetic flux density B from the equation, the magnetic flux density gradient dB / dx is obtained.

The relative velocity v of the captured magnetic particles is as follows: v = −v ₀ (11)

Therefore, by measuring the time t ₀ from the moment when the magnetic particles 41 a to 41 f are erased by the magnetic particle detector 43 to the time when the magnetic particles 41 a to 41 f are detected by the magnetic particle detector 43, the movement time detector 4
In 4, the capture position of the magnetic particles is estimated and calculated based on the movement time difference. If the capture position x = _Xl can be estimated, the magnetic flux density B and the magnetic flux density gradient dB / dx are given.
If the liquid moving speed v ₀ , liquid susceptibility χ _m , magnetic particle radius r, and liquid viscosity η are known in advance, the magnetic susceptibility χ _l of the magnetic particles can be calculated from the above equation (8).

That is, the magnetic susceptibility measuring device 25 has the above (8)
If the equation is defined, the measurement of the detection time from the magnetic particle detector 43 indicates that the magnetic flux density B and the magnetic flux density gradient dB /
Since dx can be obtained, magnetic susceptibility meter 25 is able to calculate the magnetic susceptibility chi _l of the magnetic particles.

Further, in the present embodiment, since the individual magnetic particles are identified after the magnetic particles are separated in position, a state in which a plurality of magnetic particles having different magnetic susceptibilities are mixed in a liquid can be handled. There is an advantage.

Incidentally, the tube 15 of the third embodiment is described.
Is connected to a flow cytometer 40 for detecting the affinity binding of DNA on the downstream side of the magnetic particle outlet of the solenoid coil 19. Therefore, in the above particle properties detectors and identification methods, following after the detection of the magnetic susceptibility chi _l of each magnetic particles, it is possible to detect the reaction product bound to the magnetic particles by a flow cytometer 40.

Furthermore, in the third embodiment, since the DNA in the reagent solution is modified with a fluorescent dye, if the dye is excited at a specific wavelength in the flow cytometer 40 and the fluorescence is measured. It is possible to detect whether affinity binding has occurred on the surface of the magnetic particles. Therefore, according to the present embodiment, the result of the affinity binding can be measured together with the magnetic susceptibility χ of each magnetic particle.
The NA binding reaction can be revealed.

That is, by using a plurality of particles having different magnetic susceptibility χ and identifying and separating each particle, while identifying the type of DNA on the surface of each magnetic particle, which DNA corresponds to which reagent D
It is possible to individually detect whether or not it has reacted with NA.

Therefore, in the third embodiment,
In addition to the effects of the first and second embodiments described above, there are the following specific effects.

That is, a DNA array is generally used as a method for examining the affinity reaction of a biological substance such as DNA. However, as in the third embodiment, DNA is placed on a three-dimensional surface. By arranging, the reaction efficiency of affinity binding is higher than in the case of a two-dimensional surface. In addition, the type of DNA to be immobilized can be changed for each particle having a different magnetic susceptibility, and the user can select only magnetic particles on which necessary DNA is immobilized to perform an affinity reaction. Can be handled in one reaction vessel at a time. Therefore, the customizability of the experiment is very high, and the amount of biological materials and reagents required for the experiment is extremely small.

Further, by combining with a flow cytometer, an affinity binding result can be obtained in a short time. As a result, the cost can be reduced.

In addition, in the third embodiment, the particle diameter of a magnetic particle having a known magnetic susceptibility and an unknown particle diameter is applied by applying the principle of the magnetic susceptibility measuring method for magnetic particles described above. Can also be measured.

In the measurement of the particle size of the magnetic particles, the above-described magnetic particle identification apparatus and method are applied to magnetic particles having a known magnetic susceptibility and an unknown particle size. In step (1), the capture position of the magnetic particles is estimated and calculated based on the movement time difference. Capture position of magnetic particles x = X _l
Can be estimated, the magnetic flux density B, the magnetic flux density gradient dB / dx
Is given, the liquid movement speed v ₀ , the magnetic susceptibility χ _l of the magnetic particles, the liquid susceptibility χ _m , and the liquid viscosity η are given in advance. The magnetic particle radius r can be calculated by the equation.

That is, as shown in FIG. 13, a particle size measuring device 47 for calculating the particle size of the magnetic particles is provided in the particle characteristic detector 46 instead of the magnetic susceptibility measuring device 25, If the equation (9) is defined in the detector 47, the output signal from the movement time detector 44 is received and the relative velocity v of the magnetic particle 41 is given. Can be calculated.

It is to be noted that each configuration of the third embodiment can of course be variously modified and changed. For example, magnetic particles include, in addition to diamagnetic substances, one or more magnetic substances or superconducting substances, including ferromagnetic substances, paramagnetic substances, antiferromagnetic substances, diamagnetic substances, and superconductors including high-temperature superconductors. The immiscible liquid may be a paramagnetic substance or a diamagnetic substance.

In addition, the solenoid coil may be configured so that the product of the magnetic flux density and the magnetic flux density gradient is asymmetric. For example, a configuration may be adopted in which the diameter of the solenoid decreases or the diameter of the coil decreases from the side where the magnetic particles are introduced to the side where the magnetic particles are discharged. Conversely, from the side where the magnetic particles are introduced to the side where the magnetic particles are discharged, the solenoid coil is configured so that the number of turns is reduced and reduced, or the solenoid diameter is configured to increase or the coil diameter increases. It may be configured as described above. In addition, the magnetic field generator may be constituted by permanent magnets or the like other than the solenoid coil.

Further, the particle characteristic detector includes a laser irradiator for irradiating a laser to the magnetic particles, a half mirror provided between the laser irradiator and a tube in which the magnetic particles move, and a laser reflection from the magnetic particles. It may be constituted by a photodetector for detecting light, and a half mirror provided between the photodetector and the moving path of the magnetic particles.

The biological substance to be fixed on the surface of the magnetic particles may be other than DNA, such as RNA, gene, chromosome, cell membrane, virus, specific binding protein, and the like.
Antigens, antibodies, lectins, haptens, hormones, receptors, enzymes, nucleic acids and the like may be used.

Further, as means for measuring the affinity binding of the biological substance, for example, a flow cell, a cell sorter or the like may be connected to the downstream side of the tube in addition to the flow cytometer.

Further, a magnetic particle extraction mechanism that can extract necessary particles depending on the type of the identified magnetic particles or the result of affinity binding may be provided on the downstream side of the tube.

Next, a fourth embodiment of the present invention will be described.

FIG. 14 is a diagram showing a configuration of a magnetic particle identification device according to the fourth embodiment of the present invention.

In FIG. 14, the magnetic particles have a particle size of about several μm and are made of a diamagnetic substance. The tube 50 is filled with a liquid that is incompatible with the magnetic particles. In this tube 50, magnetic particles 51 having a specific magnetic susceptibility are placed.
An introduction mechanism 52 for introduction into the inside of the camera is connected. The introduction mechanism 52 is arranged such that the magnetic particles 51 are introduced into a portion where the magnetic flux density gradient of the magnetic field generator becomes zero.

The cross-sectional shape and cross-sectional area of the introduction mechanism 52 and the tube 50 can be arbitrarily set within a range where the liquid and the magnetic particles can sufficiently move. Although not shown,
Since there is a particle isolation mechanism on the upstream side of the introduction mechanism 52 for isolating the magnetic particles, the magnetic particles are introduced into the tube from the introduction mechanism in an individually isolated state.

Both ends of the tube 50 are on the magnetic particle discharge side. Along the outer peripheral surface of the tube 50, there are provided solenoid coils 53 each having a uniform number of coil turns per unit. Further, magnetic particle detectors 56 and 57 of a particle characteristic detector 55 are provided on the outer downstream side near the two magnetic particle discharge ports of the solenoid coil 53, respectively. A magnetic particle detector 58 is also provided near the introduction mechanism 52. The particle characteristic detector 55 according to the fourth embodiment includes magnetic particle detectors 56 and 57 near the magnetic particle outlet of the solenoid coil and magnetic particles provided in the introduction mechanism 52 for detecting passage of the particles. The detector 58 and the magnetic particle detectors 56 and 58, or the time difference between the passage of the particles in the magnetic particle detectors 57 and 58,
And a speed detector 59 for calculating the speed of the vehicle.

Further, a magnetic susceptibility measuring device 61 is connected to the velocity detector 59 in the particle characteristic detector 55.

Further, a magnetic field control mechanism 60 for generating a magnetic field in the solenoid coil 53 with a predetermined magnetic field strength is connected to the solenoid coil 53. The magnetic field control mechanism 60 controls magnetic field strength, magnetic field generation, and magnetic field erasure.

Next, the operation of the fourth embodiment will be described.

Each of the magnetic particles 5 introduced by the introduction mechanism 52
1 exists in a state where the inside of the tube 50 is isolated, but when the magnetic particles 51 are not affected by an external magnetic field, they stay in the liquid after introduction. Outside the tube 50, a solenoid coil 53 having a uniform number of turns on the circumference is provided as a magnetic field generator for artificially generating a magnetic field for the magnetic particles 51 inside the tube 50. I have.

Now, consider a case where the magnetic field control mechanism 60 causes the solenoid coil 53 to generate a magnetic field of a predetermined strength.

In the solenoid coil 53 according to the fourth embodiment, since the number of coil turns per unit is configured to be uniform, as shown in FIG. It becomes largest near the magnetic particle detectors 56 and 57 which are the magnetic particle outlets of the coil 53.

Here, according to the above equation (6), the moving speed v of the magnetic particles is determined by the magnetic susceptibility χ _l , χ
_m and the magnetic flux density, the magnitude of the magnetic flux density gradient, and the size of the magnetic particles, the relative velocity v = 0 at the position of the introduction mechanism 52 where the product of the magnetic flux density and the magnetic flux density gradient becomes zero, for example. It is.

However, in the case of diamagnetic particles, the relative velocity v of the magnetic particles with respect to the liquid is accelerated as the magnetic flux density gradient approaches a position where the magnetic flux density has a minimum value, and the magnetic flux density gradient has a minimum value point (near the magnetic particle detector 57). , The relative speed v becomes the maximum value. Conversely, in the case of paramagnetic particles, the relative velocity v of the magnetic particles with respect to the liquid becomes maximum at the position where the magnetic flux density gradient has a maximum value (near the magnetic particle detector 56).

In the present embodiment, the magnetic particle is individually identified by the particle characteristic detector detecting a change in the velocity of the magnetic particle.

As shown in FIG. 16, the magnetic particle detectors 56 to 58 each include an optical fiber for irradiating the magnetic particles with light, and a photodetector provided at the opposite end of the optical fiber for detecting light. And detects the magnetic particles by detecting the light blocking due to the passage of the magnetic particles.

That is, the magnetic particle detector 58 comprises: an optical fiber 67 for irradiating the magnetic particles in the introduction mechanism 52 with light;
A light detector 68 is provided at the opposite electrode of the optical fiber 67 via the introduction mechanism 52. The magnetic particle detector 56 includes an optical fiber 63 for irradiating the magnetic particles in the tube 64 with light, and a photodetector 64 installed at the opposite electrode of the optical fiber 63 via the tube 64. I have. Similarly, the magnetic particle detector 57 includes an optical fiber 65 for irradiating the magnetic particles in the tube 64 with light, and a photodetector 66 installed at a counter electrode of the optical fiber 65 via the tube 64.
It is composed of

Therefore, as described above, when the moving speed v is measured at the position of the magnetic particle outlet (the magnetic particle detectors 56 and 57) where the effect of the magnetic flux density and the magnetic flux density gradient is the largest, the magnetization of each magnetic particle is obtained. The rate difference can be detected with the highest sensitivity. At the same time, the magnetic particle detector 56
Are magnetic particles detected by the magnetic particle detector 5
The magnetic particles detected at 7 can be identified as diamagnetic particles.

[0182] Incidentally, the above (8), since it is possible to calculate the magnetic susceptibility chi _l of the magnetic particles, as shown in FIG. 14, the subsequent particle characteristics detector 55, equation (8) is defined If the magnetic susceptibility measuring device 61 is provided,
By receiving the output signal from the velocity detector 59 and giving the relative velocity v of the magnetic particles 51, the known liquid magnetic susceptibility χ _m , magnetic particle radius r, liquid viscosity η, magnetic flux density B, and magnetic flux density gradient dB / based on the dx, magnetic susceptibility meter 61 is able to calculate the magnetic susceptibility chi _l of the magnetic particles 51.

Further, in the fourth embodiment, FIG.
If a particle size measuring device for calculating the particle size of the magnetic particles defined by the above equation (9) is provided instead of the magnetic susceptibility measuring device 61 shown in FIG. Then, the relative diameter v of the magnetic particles is given, so that the particle diameter measuring device can calculate the particle radius r of the magnetic particles.

It should be noted that each configuration according to the fourth embodiment can be variously modified and changed.

For example, when magnetic particles are introduced from the introduction mechanism in a state where no magnetic field is generated in the tube, and when a plurality of types of magnetic particles are introduced into the tube, a magnetic field generator instantaneously generates a magnetic field. Each magnetic particle may be identified by measuring the moving speed with a particle characteristic detector while individually separating the magnetic particles according to the magnetic susceptibility of each magnetic particle.

The magnetic particles include, in addition to the diamagnetic substance,
Of the ferromagnetic material, paramagnetic material, antiferromagnetic material, diamagnetic material or superconductor including high-temperature superconductor, it can be composed of one or more magnetic materials or superconductor materials. Further, the immiscible liquid may be any of a paramagnetic substance and a diamagnetic substance. In addition to filling the inside of the tube, besides liquid,
It may be gas or vacuum.

The solenoid coil has a distribution having a maximum value,
What is necessary is just to be comprised so that it may have a minimum value. For example, a configuration may be adopted in which the diameter of the solenoid decreases or the diameter of the coil decreases from the side where the magnetic particles are introduced to the side where the magnetic particles are discharged. Conversely, the solenoid coil is configured so that the number of turns decreases and decreases from the side where magnetic particles are introduced to the side where magnetic particles are discharged, or the solenoid diameter is configured to increase, or the coil diameter is monotonic. May be configured so as to increase the number. Alternatively, the number of turns of the solenoid coil, the diameter of the solenoid coil, and the coil diameter may be uniform. Further, the magnetic field generator may be constituted by a permanent magnet or the like in addition to the solenoid coil.

Note that the magnetic particle detectors 56, 57, 58
A laser irradiator that irradiates a laser to the magnetic particles, a half mirror provided between the laser irradiator and a tube in which the magnetic particles move, a photodetector that detects laser reflected light from the magnetic particles, It may be constituted by a half mirror provided between the detector and the moving path of the magnetic particles. Alternatively, an annular conductor provided on the outer downstream side near the magnetic particle discharge port, and an electromotive force detector connected to the annular conductor and detecting a change in induced electromotive force generated by movement of the magnetic particles, ,
A speed detector connected to the electromotive force detector to calculate the speed of the magnetic particles from a detection signal pattern of the electromotive force detector.

On the other hand, a bio-related substance such as DNA may be fixed on the surface of the magnetic particles. Further, biologically-related substances include, for example, RNA, genes, chromosomes, cell membranes, viruses, specific binding proteins, antigens, antibodies, lectins, haptens, hormones, receptors, enzymes,
It may be a nucleic acid or the like. Further, as a means for measuring the affinity binding of such a biological substance, a flow cytometer, a flow cell, a cell sorter, etc. are connected to the downstream side of the tube,
A configuration in which magnetic particles are identified and separated based on the magnetic susceptibility χ and the particle size of the magnetic particles, so that it is possible to individually detect which DNA has reacted with which reagent DNA while identifying the type of DNA on the surface of each magnetic particle. It does not matter.

In addition, a magnetic particle extraction mechanism that can extract necessary particles depending on the type of the identified magnetic particles may be provided on the downstream side of the tube.

Next, a fifth embodiment of the present invention will be described.

FIG. 17 is a diagram showing a configuration of a magnetic particle identification device according to the fifth embodiment of the present invention.

In FIG. 17, the magnetic particles 1
6 is filled with a liquid that is incompatible with
5 is connected to an introduction mechanism 17 for introducing the magnetic particles 16 into the tube 15. The magnetic particles 16 have a size of several μm.
It has a particle size of about m to several hundred μm and is made of a ferromagnetic substance.

The introduction mechanism 17 is arranged so that the magnetic particles 16 are introduced into the center of the tube 15. The cross-sectional shape and cross-sectional area of the introduction mechanism 17 and the tube 15 can be arbitrarily set as long as the liquid and the magnetic particles can sufficiently flow.

Now, the pipe 15 is made of a transparent material, the cross section of the pipe 15 is circular, and the pipe diameter is several tens to several hundreds mm. The tube 15 is provided with a liquid transport mechanism 18 for moving the fluid inside the tube at a predetermined speed.

Outside the tube 15, magnetic particles 16 inside the tube
A pair of electromagnets 71 is provided as a magnetic field generator for artificially generating a magnetic field. The electromagnets 71 are opposed to each other with the tube 15 interposed therebetween so that the magnetic flux density is asymmetric from the side where the magnetic particles are introduced to the side where the magnetic particles are discharged. The electromagnet 71 is connected to the magnetic field control mechanism 26 that controls the magnetic field strength, the generation of the magnetic field, and the elimination of the magnetic field, and the distance between the opposing electromagnets 71 can be changed as appropriate.

Further, two magnetic particle detectors 22 and 23 are provided along both ends of the electromagnet 71 along the tube 15. The magnetic particle detector 22 is provided on the outer upstream side of the magnetic particle inlet of the electromagnet 71, and the magnetic particle detector 23
Is provided on the outer downstream side of the magnetic particle discharge port of the electromagnet 71.

The speed detector 24 connected to the two magnetic particle detectors 22 and 23 has a known time difference between the detection signals of the magnetic particles at the respective positions where the magnetic particle detectors 22 and 23 are installed. The speed of the magnetic particles 16 is calculated based on a certain two magnetic particle detector installation distances.

The magnetic particle detectors 22, 23
And the velocity detector 24 constitute a particle characteristic detector 21.

The susceptibility measuring device 25 is connected to the subsequent stage of the particle characteristic detector 21. The magnetic susceptibility measuring device 25 calculates the magnetic susceptibility of the magnetic particles 16 based on the known physical quantity and the detected speed of the magnetic particles.

Next, the operation of the fifth embodiment will be described.

The inside of the tube 15 is made of a diamagnetic material, and the magnetic particles 16
Liquid incompatible with the liquid transport mechanism 18
As a result, the liquid inside the tube 15 is moving at a predetermined speed in the direction of the arrow shown in the figure. Although not shown, there is a particle isolation mechanism upstream of the introduction mechanism 17 for isolating the magnetic particles in the liquid. Therefore, the magnetic particles 16 are individually isolated from the introduction mechanism 17. It is introduced inside the tube 15. After the introduction, each magnetic particle 16 moves in a state where the inside of the tube 15 is isolated, but the magnetic particle 16 flows at the same speed as the liquid when there is no influence of the external magnetic field.

Now, the magnetic field control mechanism 26 controls the electromagnet 7
Consider a case where 1 generates a magnetic field of a predetermined strength.

The electromagnet 71 according to the present invention is similar to the electromagnet 71 shown in FIG.
As shown in (a) and (b), a pole tip in which the magnetic flux density is asymmetric and the magnetic flux density in the width direction of the tube 15 is uniform from the side where the magnetic particles are introduced to the side where the magnetic particles are discharged. It has a shape. The magnetic flux density of the electromagnet of the fifth embodiment has a maximum value at the particle outlet as shown in FIG. Further, the magnetic flux density gradient with respect to the moving direction of the liquid has a maximum value at the particle inlet as shown in FIG.

The liquid immiscible with the magnetic particles 16 filled in the pipe 15 is supplied to the liquid transport mechanism 18 at a predetermined velocity v _0.
Is moving inside the pipe 15. By the magnetic field control mechanism 26,
When a magnetic field is generated in the electromagnet 71 at a predetermined magnetic field strength, the tube 15 inside of the magnetic particles 16, (3) a magnetomotive force F _m by a magnetic field of the formula results.

On the other hand, when the magnetic particles 16 move at a relative speed v to the liquid due to the magnetomotive force, the viscous force Fv of the fluid
Is expressed by the above equation (4).

When the magnetic particles move by the magnetomotive force, the above equation (5) holds. At this time, the relative velocity v of the magnetic particles 16 is as shown in the above equation (6), and the magnitude of the relative velocity v is the magnetic susceptibility χ _l , χ _m of the magnetic particles and the liquid, the magnetic flux density, and the magnitude of the magnetic flux density gradient. It can be seen that the size is determined by the magnetic particle size.

As described above, the electromagnet of the present invention is configured to be asymmetric from the side where the magnetic particles are introduced to the side where the magnetic particles are discharged, and the effects of the magnetic flux density and the magnetic flux density gradient are affected by the magnetic properties of the electromagnet. Largest at the particle outlet. Therefore, if the relative velocity v is measured at this position, the difference in the magnetic susceptibility of each magnetic particle can be detected with the highest sensitivity. That is, individual magnetic particles can be identified with the highest sensitivity.

Now, when the magnetic particle size is constant and the absolute values of the magnetic susceptibility χ ₁ , χ ₂ , χ ₃ and the magnetic susceptibility χ _m of the magnetic particles have the relationship of the above equation (7), The relative velocity v of the magnetic particles with respect to the magnetic susceptibility of the particles and the liquid is shown in FIG.
The relationship is as shown in FIG. In each graph, the horizontal axis represents the distance in the moving direction of the liquid, and the vertical axis represents the relative velocity v.

The magnetic particles of the present embodiment are made of a ferromagnetic substance and have a specific magnetic susceptibility. In general, the relative velocity changes greatly when the sign of the magnetic property of the magnetic particle and that of the liquid are opposite (one is a diamagnetic substance and the other is a paramagnetic substance), and as the magnetic susceptibility of the magnetic particle increases. .

Further, considering these results and FIG. 18, in the case of paramagnetic particles, the relative velocity v of the magnetic particles with respect to the liquid becomes maximum at the position where the magnetic flux density gradient takes the maximum value, It moves inside the pipe faster (with acceleration) than the moving speed. Conversely, in the case of diamagnetic particles, the relative velocity v of the magnetic particles to the liquid is minimized at the position where the magnetic flux density gradient has a maximum value. Relative to the liquid is reduced.

Therefore, the magnetic particle detector 2 provided outside and upstream of the magnetic particle inlet of the electromagnet 71 according to the present invention.
2, and the passage of the particles is detected by the magnetic particle detector 23 provided outside and downstream of the magnetic outlet of the electromagnet 71 where the magnetic flux density gradient becomes maximum. Since the installation distances of these two magnetic particle detectors 22 and 23 are known, the speed detector 24 determines the magnetic distance based on the time difference between the detection signals of the magnetic particles at the installation positions of the magnetic particle detectors 22 and 23. The relative velocity v of the particles 16 is determined.

By transforming the above equation (6), the magnetic susceptibility χ _l of the magnetic particles is given by the above equation (8). Therefore, the measured relative velocity v of the magnetic particles and the magnetic susceptibility Given χ _m , magnetic particle radius r, liquid viscosity η, magnetic flux density B, and magnetic flux density gradient dB / dx, the magnetic susceptibility χ _l of the magnetic particles can be calculated.

That is, if the above equation (8) is defined in the susceptibility measuring device 25, the relative speed v of the magnetic particles is given by receiving the output signal from the moving time detector (not shown). As a result, the magnetic susceptibility measuring device 25
It is possible to calculate the magnetic susceptibility χ _l.

Furthermore, in the present invention, the magnetic particles 16
By applying the principle of the magnetic susceptibility measuring method in the above, it is also possible to measure the particle diameter of magnetic particles whose magnetic susceptibility is known and whose particle diameter is unknown.

In the measurement of the particle size of the magnetic particles, the magnetic particle identification apparatus and method described above were applied to a magnetic particle having a known magnetic susceptibility.
This is performed on magnetic particles whose particle size is unknown, and the relative velocity v of the magnetic particles to the liquid is calculated. The relative velocity v of the magnetic particles can be measured, the magnetic susceptibility χ _l of the magnetic particles, the magnetic susceptibility χ _{m of} the liquid, the liquid viscosity η, the magnetic flux density B, the magnetic flux density gradient dB /
If dx is known, the magnetic particle radius r is calculated by the above equation (9) by modifying the above equation (8).

That is, as shown in FIG. 21, a particle size measuring device 32 for calculating the particle size of the magnetic particles 16 is provided in place of the magnetic susceptibility measuring device 25, and the particle size measuring device 32 is provided with the above (9). If the equation is defined, the output signal from the movement time detector (not shown) is received, and the relative velocity v of the magnetic particle 16 is given. Can be calculated.

Incidentally, each configuration of the fifth embodiment of the present invention can of course be variously modified and changed. For example, magnetic particles can be paramagnetic, antiferromagnetic,
Among the superconductors including diamagnetic material or high-temperature superconductor, it can be composed of one or more magnetic materials or superconductor materials, and the immiscible liquid is either a paramagnetic material or a diamagnetic material. There may be. What fills the inside of the flow path may be gas or vacuum other than liquid.

Furthermore, the electromagnet may be configured so that the magnetic flux density gradient is asymmetric and has a maximum value. For example, the pole tip portion of the electromagnet may be circular other than rectangular.

The magnetic flux density distribution in the flow channel width direction may not be uniform, and may be a symmetric distribution. Further, the magnetic field generator may be constituted by, for example, a solenoid coil, a permanent magnet, a superconducting magnet, etc., in addition to the electromagnet in the fifth embodiment.

On the other hand, a bio-related substance such as DNA may be fixed on the surface of the magnetic particles. Examples of the bio-related substance include RNA, gene, chromosome, cell membrane, and the like.
It may be a virus, a specific binding protein, an antigen, an antibody, a lectin, a hapten, a hormone, a receptor, an enzyme, a nucleic acid, or the like.

As a means for measuring the affinity binding of such a biological substance, as shown in FIG.
A flow cytometer 40, a flow cell, a cell sorter, etc. are connected downstream of the tube 15, and identify and separate the magnetic particles 16 based on the magnetic susceptibility χ and the particle size of the magnetic particles 16 to specify the type of DNA on the surface of each magnetic particle. However, the configuration may be such that it is possible to individually detect which DNA has reacted with which reagent DNA.

Further, a magnetic particle extraction mechanism for extracting necessary particles depending on the type of the identified magnetic particles may be provided downstream of the tube.

[0224]

As described above, according to the present invention, it is possible to use magnetic particles composed of a plurality of materials to individually identify and separate particles even when the types of substances to be detected are extremely large. It is an object of the present invention to provide a magnetic particle identification device and a magnetic particle identification method applicable to affinity binding.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of a first embodiment of a magnetic particle identification device according to the present invention.

FIG. 2 is a diagram specifically showing a configuration of the magnetic particle identification device according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of magnetic particle detectors 22 and 23 of FIG.

4A and 4B show characteristics of a solenoid coil according to the first embodiment, in which FIG. 4A shows a relationship between a length and the number of turns, and FIG. 4B shows a relationship between a length and a magnetic flux density. The figure shown,
(C) is a diagram showing the relationship between the length and the magnetic flux density gradient.

5A and 5B show relative velocity distribution characteristics with respect to a distance in a moving direction of a liquid in the first embodiment, and show (a) characteristics in the case of diamagnetic particles / diamagnetic fluid, and FIG. ) Is a diagram showing characteristics in the case of paramagnetic particles / diamagnetic liquid,
(C) is a diagram showing characteristics in the case of diamagnetic particles / paramagnetic liquid, and (d) is a diagram showing characteristics in the case of paramagnetic particles / paramagnetic liquid.

FIG. 6 is a diagram showing an example of the detection time in the magnetic particle detectors 22 and 23 in the case of paramagnetic particles and diamagnetic particles.

FIG. 7 is a diagram showing a configuration of a magnetic particle identification device according to a modification of the first embodiment of the present invention.

FIG. 8 is a diagram showing a configuration of a magnetic particle identification device according to a second embodiment of the present invention.

FIG. 9 shows a magnetic particle discharge port of a solenoid coil 19;
FIG. 9 is a characteristic diagram showing an example of a detection signal pattern in the electromotive force detector 37 when three magnetic particles are sequentially discharged.

FIG. 10 is a diagram showing a configuration of a magnetic particle identification device according to a third embodiment of the present invention.

FIG. 11 is a diagram illustrating the operation of the magnetic particle identification device according to the third embodiment.

FIG. 12 is a diagram illustrating a relationship between magnetic particles and a signal detection time according to a third embodiment.

FIG. 13 is a diagram showing a configuration of a magnetic particle identification device according to a modification of the third embodiment of the present invention.

FIG. 14 is a diagram illustrating a configuration of a magnetic particle identification device according to a fourth embodiment of the present invention.

15A and 15B show characteristics of a solenoid coil 53 according to a fourth embodiment, wherein FIG. 15A is a characteristic diagram showing a relationship between length and magnetic flux density, and FIG. FIG. 3 is a characteristic diagram showing a relationship with the relationship.

FIG. 16 shows the magnetic particle detectors 56, 57 and 58 of FIG.
FIG. 3 is a diagram showing the configuration of FIG.

FIG. 17 is a diagram illustrating a configuration of a magnetic particle identification device according to a fifth embodiment of the present invention.

FIGS. 18A and 18B show a structure of an electromagnet 71 according to a fifth embodiment, wherein FIG. 18A is a plan view and FIG. 18B is a side sectional view.

19A and 19B show characteristics of the electromagnet according to the fifth embodiment, in which FIG. 19A shows a relationship between length and magnetic flux density,
(B) is a diagram showing the relationship between the length and the magnetic flux density gradient with respect to the moving direction of the liquid.

FIG. 20 is a diagram showing a relationship between magnetic susceptibility of magnetic particles and liquid and relative velocity v of magnetic particles.

FIG. 21 is a diagram showing a configuration of a magnetic particle identification device according to a modification of the fifth embodiment of the present invention.

FIG. 22 is a diagram showing a configuration of a magnetic particle identification device according to another modification of the fifth embodiment of the present invention.

[Explanation of symbols]

 1,15 tube, 2,16 magnetic particle, 3,17 introduction mechanism, 4,19 solenoid coil, 6,7,22,23 magnetic particle detector, 8,24 speed detector, 10,21,35 particle characteristic detection , 11, 25 magnetic susceptibility measuring device, 26 magnetic field control mechanism, 28 laser irradiator, 29a, 29b half mirror, 30 photodetector. 32 particle size analyzer, 37 electromotive force detector.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G053 AB06 BA04 BA05 BB03 BB11 BC14 CA03 DA01 DA02 DA10 DB02 DB05

Claims (27)

[Claims] An apparatus for identifying magnetic particles using a magnetic particle having a specific magnetic susceptibility, a tube through which the magnetic particles pass, and a magnetic field generator for generating a magnetic field inside the tube. Introducing means for introducing a plurality of magnetic particles having different magnetic susceptibilities into the tube; magnetic field generating means for applying a magnetic field to the inside of the tube through which the magnetic particles pass to change the speed of the magnetic particles; And a speed detecting means for detecting the speed of the magnetic particles according to claim 1, wherein the magnetic particles are identified by a change in the speed of the magnetic particles. 2. The method according to claim 1, wherein the introduction means introduces the magnetic particles into the tube at a position where a magnetic flux density gradient of a magnetic field generated by the magnetic field generation means becomes zero inside the tube. The magnetic identification device according to claim 1, wherein: 3. The magnetic particle identification apparatus according to claim 1, wherein the inside of the tube is filled with a fluid, and the introduction unit introduces the magnetic particles into the tube by a flow of the fluid. 4. A magnetic particle detecting means for detecting the magnetic particles discharged by the movement of the fluid with respect to the magnetic particles moving by the flow of the fluid when the fluid in the tube is moved at a constant speed. The magnetic force is acted on by the magnetic field generating means, and after the particles move at a speed different from the moving speed of the fluid in the tube, the magnetic force by the magnetic field generating means is erased to detect the magnetic particles. 4. The magnetic particle identification apparatus according to claim 3, wherein the magnetic particles are identified based on a time at which the magnetic particles are detected after the magnetic field is erased by the means. 5. The magnetic particle identification device according to claim 1, wherein the magnetic field generation means generates a magnetic field gradient that is asymmetric with respect to a moving direction of the magnetic particles in the tube. 6. The magnetic field generating means is constituted by a solenoid coil, and is provided such that any one of the number of turns of the solenoid coil, the diameter of the solenoid coil, and the diameter of the coil increases or decreases with respect to the moving direction of the magnetic particles. The magnetic particle identification device according to claim 5, wherein the magnetic particle identification device is used. 7. The speed detecting means has at least two magnetic particle detectors, and detects a difference in time when the magnetic particles pass through the two magnetic particle detectors, thereby detecting the speed of the magnetic particles. 2. The method according to claim 1, wherein
7. The magnetic particle identification device according to item 1. 8. The magnetic particle detector includes a light source and a light detector that receives light from the light source, and detects light incident on the light detector that changes as the magnetic particles pass. The magnetic particle identification device according to claim 7, wherein the magnetic particles are detected by: 9. The light source of the magnetic particle detector comprises a laser irradiator for irradiating a laser, and the photodetector detects laser reflected light from magnetic particles moving in the tube, and detects the magnetic particle. The device further includes a first half mirror provided between the laser irradiator and the tube in which the magnetic particles move, and a second half mirror provided between the photodetector and the tube in which the magnetic particles move. The magnetic particle identification device according to claim 8, comprising: two half mirrors. 10. An optical fiber for transmitting light from the light source to the magnetic particles in the tube, wherein the photodetector is provided at a position facing the optical fiber and the tube. The magnetic particle identification device according to claim 8, wherein 11. The speed detecting means detects a conductive wire provided adjacent to the magnetic field generating means in the direction in which the tube extends, and an electromotive force generated in the conductive wire when a magnetic particle moves in the tube. 2. The magnetic particle identification device according to claim 1, further comprising: an electromotive force detecting means for detecting a moving speed of the magnetic particles based on a signal from the electromotive force detecting means. apparatus. 12. The speed detecting means has an imaging means for acquiring an image of a magnetic particle passing through the inside of the tube,
2. The magnetic particle identification device according to claim 1, wherein a moving speed of the magnetic particles is detected based on the acquired image. 13. A magnetic particle having a different specific magnetic susceptibility and suspended in a liquid incompatible with the particle with a biological substance fixed on the surface, and a reagent labeled with the magnetic particle. Or a reactor for reacting a biological substance, a discrete means connected to the reactor and discretely dispersing the magnetic particles in a liquid, and a tube for passing the magnetic particles connected to the discrete means therein, A liquid conveying means for feeding the liquid into the tube at a predetermined speed; and a magnetic field generated in the tube. The magnetic force acting on the magnetic particles passing through the tube by the magnetic field causes a speed of the magnetic particles moving in the tube. A magnetic field generating means for changing the moving speed of the particles, a particle identification means for identifying the particles by detecting a change in the speed of the magnetic particles, and a position of the tube where the magnetic field generating means is provided. A biological substance reaction detecting means for specifying an affinity binding of the particles to a reagent or a biological substance provided downstream; anda signal from the particle identifying means and a signal from the biological substance reaction detecting means. A magnetic particle identification device characterized by detecting an affinity binding state of a particle surface corresponding to an identified particle by using the method. 14. A magnetic particle having a different specific magnetic susceptibility and suspended in a liquid immiscible with the particle with a biological substance fixed on the surface, and a reagent labeled with the magnetic particle Or a reactor for reacting a bio-related substance; discrete means connected to the reactor, for discretely dispersing the magnetic particles in a liquid; and a tube for passing the magnetic particles connected to the discrete means therein, Liquid transport means for feeding the liquid to the pipe at a predetermined speed; and a magnetic field generated in the pipe, and a magnetic force acting on a plurality of types of magnetic particles passing through the pipe due to the magnetic field. A magnetic field generating means for changing the moving speed of the particles, and a magnetic field provided downstream of the magnetic field generating means of the tube and moving with the transport of the liquid when the magnetic field generated by the magnetic field generating means is erased. A magnetic particle identification means for individually identifying the magnetic particles from the time from when the magnetic field is erased until the magnetic particles are detected, and downstream of the position of the tube where the magnetic particle identification means is provided. A biological substance reaction detecting means for specifying an affinity binding of the particles to a reagent or a bio-related substance provided in, comprising: a signal from the particle identifying means and a signal from the biological substance reaction detecting means. A magnetic particle identification apparatus for detecting an affinity binding state of a particle surface corresponding to an identified particle using the apparatus. 15. The biological substance reacting with the magnetic particles is labeled with a fluorescent dye, and the biological substance reaction detecting device is a flow cell, a flow cytometer, or a cell sorter. The magnetic particle identification device according to any one of the above. 16. The biological substance immobilized on the surface of the magnetic particle may be DNA, RNA, gene, chromosome, cell membrane, virus, specific binding protein, antigen, antibody, lectin, hapten, hormone, receptor, enzyme. 15. The magnetic particle identification device according to claim 13, wherein the magnetic particle identification device contains a substance selected from the group consisting of nucleic acids and nucleic acids. 17. A magnetic susceptibility detecting means or a particle diameter detecting means for calculating a magnetic susceptibility or a particle diameter of the magnetic particle from a velocity change of the magnetic particle and a known physical quantity of the magnetic particle. The magnetic particle identification device according to claim 1, wherein: 18. A magnetic susceptibility detecting means or a magnetic particle diameter detecting means for calculating a magnetic susceptibility or a particle diameter of the magnetic particles from a time from when the magnetic field is erased to when the magnetic particles are detected and a known physical quantity of the magnetic particles. 15. The method according to claim 4, further comprising: means.
6. A magnetic particle identification device according to any one of the preceding claims. 19. The method according to claim 1, wherein the magnetic particles include at least one of a ferromagnetic material, a paramagnetic material, a diamagnetic material, and a superconductor. Magnetic particle identification device. 20. A method for identifying magnetic particles by passing magnetic particles having a specific magnetic susceptibility into the interior of a tube, generating a magnetic field inside the tube, and applying a magnetic force to the magnetic particles. Introducing a plurality of magnetic particles having different specific magnetic susceptibility into the inside of the tube; and applying a magnetic force to the magnetic particles introduced into the inside of the tube to change the speed of the magnetic particles, Detecting a change in velocity of the magnetic particles. 21. A method for introducing magnetic particles having a specific magnetic susceptibility into a tube in which a fluid moves, generating a magnetic field inside the tube, and applying a magnetic force to the magnetic particles to identify the magnetic particles. A step of introducing a plurality of magnetic particles having different specific magnetic susceptibilities into a tube by transporting a fluid, and applying a magnetic force to the magnetic particles introduced into the tube to form a fluid in the tube. Moving the magnetic particles at a speed different from the conveying speed, erasing the magnetic force acting on the magnetic particles, and detecting the particles conveyed downstream of the portion of the tube where the magnetic force acts And a step of detecting the time from when the magnetic force is erased to when the particles are detected. 22. A magnetic particle having a specific magnetic susceptibility is introduced into a tube in which a fluid moves, and a magnetic field is generated inside the tube to cause a magnetic force to act on the magnetic particle to identify the magnetic particle. A method comprising: suspending magnetic particles having different specific susceptibilities and immobilizing a biological substance on the surface thereof in a liquid incompatible with the magnetic particles; and labeling the magnetic particles. A step of reacting a reagent or a biological substance, a step of mutually separating the magnetic particles in a liquid, a step of sending a liquid in which the discrete magnetic particles are suspended into a tube at a predetermined speed, A step of generating a magnetic field inside and applying a magnetic force to the magnetic particles passing through the tube to change the moving speed of the magnetic particles, and identifying the magnetic particles by detecting a change in the moving speed of the magnetic particles The process of Detecting the affinity binding of the magnetic particles with the reagent or the biological substance, and detecting the affinity binding of the magnetic particles with the reagent or the biological substance with respect to the identified magnetic particles. Characteristic magnetic particle identification method. 23. A magnetic particle having a specific magnetic susceptibility is introduced into a tube in which a fluid moves, and a magnetic field is generated inside the tube to cause a magnetic force to act on the magnetic particle to identify the magnetic particle. A method comprising: suspending a magnetic particle having a specific substance having a different specific magnetic susceptibility and immobilizing a biological substance on a surface thereof in a liquid incompatible with the magnetic particle; and labeling the magnetic particle. A step of reacting a reagent or a biological substance, a step of mutually dispersing the magnetic particles in a liquid, a step of sending a liquid in which the discrete magnetic particles are suspended into a tube at a predetermined speed, and A step of generating a magnetic field inside, applying a magnetic force to a plurality of magnetic particles moving in the tube, and changing the moving speed of the magnetic particles, and a step of erasing the magnetic force acting on the magnetic particles, The magnetic force in the pipe A step of detecting magnetic particles conveyed downstream of the part where the magnetic particles are conveyed; a step of detecting the time from when the magnetic force is erased to when the magnetic particles are detected; and Discriminating; detecting the affinity of the magnetic particles with a reagent or a biological substance; and detecting the affinity binding of the magnetic particles with the reagent or the biological substance to the identified magnetic particles. A magnetic particle identification method, comprising: 24. The magnetic particle identification device according to claim 5, wherein said magnetic field generating means has an electromagnet. 25. The magnetic particle identification apparatus according to claim 5, wherein said magnetic field generating means has a permanent magnet. 26. The magnetic particle identification apparatus according to claim 5, wherein said magnetic field generating means has a superconducting magnet. 27. The magnetic field generating means has a pole tip shape such that the magnetic flux density is asymmetric and the magnetic flux density in the width direction of the tube is uniform from the side where magnetic particles are introduced to the side where magnetic particles are discharged. The magnetic particle identification device according to any one of claims 25 to 27, wherein: