JP2000088863A - Dispensing needle body for microdispenser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dispensing needle body for a microdispenser capable of dispensing stably a sample solution reserved in a vertically split groove a prescribed amount by a prescribed amount, capable of dispensing the solution in a condition to separate surely the solution each other with respect to a dispensing plate, and capable of dispensing a small amount of the sample solution into a large number of samples. SOLUTION: A dispensing needle body 25 is immersed into a pocket provided a sample plate to hold a sample solution, and then the needle body 25 is brought into contact on the a dispensing plate to dispense the sample solution dotlikely. A tip part of the needle body 25 is formed into a tapered form, comprising a prescribed size of an abutting face. A crosswise hole 25b penetrated in a direction orthogonal to an axial line and a vertical groove 25d having a very small space communicated with the hole 25b, extended to a direction of the axial line and splitting the abutting face are formed in the tip part of the needle body 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for specifying the components of various sample solutions such as a biological sample solution and a multi-component substance solution. The present invention relates to a dispensing needle of a microdispensing device for dispensing a minute amount of water.

[0002]

For example, when a component in a sample solution is specified by a surface plasmon resonance angle detecting device, the tip surface of the dispensing needle to which the sample solution is attached is placed on the dispensing plate. A so-called stamp method in which a sample solution is dispensed in a small order of 0.2 nl to 5 nl in contact therewith is known.

The dispensing needle of this microdispensing apparatus is made of a metal material such as stainless steel or a sintered material such as ceramics, and has a shaft end having a diameter of about 2 mm and a tip surface having a diameter of about 50 to 20 mm.
It is formed into a tapered tapered shape having a diameter of 0 μm, and a vertical groove is formed at the center of the tip end with an open side surface. The dispensing needle is immersed in the sample solution stored in each pocket of the sample plate. After the sample solution is filled in the vertically divided groove, the tip surface of the dispensing needle is pressed against the dispensing plate, and the sample solution is dispensed in a dot shape by the surface tension.

However, in the above-mentioned dispensing needle, when the needle is immersed in each pocket and filled in the vertical groove, the sample solution hardly penetrates into the vertical groove, and a predetermined amount of the sample The solution could not be reliably filled. For this reason, the number of dispensed dots by one filling is not constant,
There is a problem that it takes time to manage the dispensing work.

[0005] In addition, at the initial stage of dispensing, since there is a height difference between the sample solutions filled in the vertically divided grooves, there is a possibility that the dispensed sample solution has a large amount of dots and the dots of the dispensed sample solution overlap with each other. . For this reason, there is a problem that component detection cannot be accurately performed due to mixing of the dispensed sample solutions. Furthermore, if the height difference of the sample solution in the vertical groove decreases with the progress of the dispensing work, the amount of dispensed will be reduced and the amount of sample solution required for detection cannot be dispensed stably. are doing.

Further, when the dispensing needle is immersed in the sample solution in each pocket of the sample plate and pulled up, the excess sample solution remains attached to the outer peripheral surface of the tip. ing. In this state, when the dispensing needle tip is pressed against the dispensing plate and dispensed, the sample container attached to the outer peripheral surface as well as the sample solution drawn out from the vertically divided groove is also dispensed on the dispensing plate. The dot diameter of the sample solution that has been injected increases, and there is a risk of mixing with another sample solution that is simultaneously or later dispensed. In this case, since the sample solution itself to be detected becomes unknown, the component detection could not be performed effectively. Further, the amount of the consumed sample solution is increased, and the component identification cannot be effectively performed. Particularly, in the case of a biological sample, the amount of the collected biological sample solution itself is extremely small, so that it has been difficult to dispense the sample to the number of samples necessary for specifying the biological sample.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional drawbacks. An object of the present invention is to stably divide a predetermined amount of a sample solution stored in a vertically divided groove. It is an object of the present invention to provide a dispensing needle for a microdispensing device which can be poured.

Another object of the present invention is to provide a dispensing needle for a microdispensing apparatus capable of dispensing a sample solution on a dispensing plate in a state of being surely separated from each other. It is in.

A further object of the present invention is to provide a dispensing needle for a microdispensing device capable of dispensing a large number of samples with a small amount of sample solution.

[0010]

[Means for Solving the Problems] Therefore, claim 1
After dispensing the dispensing needle into the pocket provided in the sample plate to hold the sample solution, the dispensing needle is brought into contact with the dispensing plate to dispense the sample solution in a dot form. In the dispensing device, the distal end of the dispensing needle body has a tapered tapered shape in which the contact surface with the dispensing plate has a predetermined size, and communicates with the lateral hole penetrating in the direction orthogonal to the axis and the lateral hole and extends in the axial direction. It is characterized in that a vertical groove of a minute gap extending and dividing the contact surface is formed.

The dispensing needle is immersed in a pocket provided in the sample plate to hold the sample solution, and then the dispensing needle is brought into contact with the dispensing plate to contact the sample solution. In a microdispensing device for dispensing a dot in a dot shape, the tip of the dispensing needle body has a tapered tapered shape in which the contact surface with the dispensing plate has a predetermined size, and a lateral hole penetrating in a direction orthogonal to the axis. It is characterized in that a longitudinal groove of a minute gap that extends in the axial direction in communication with the lateral hole and divides the contact surface is formed, and a hydrophobic coating is provided on the outer peripheral surface of the tip excluding the contact surface.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a dispensing needle. FIG. 2 is a longitudinal sectional view of the dispensing needle. FIG. 3 is a perspective view showing the outline of the microdispensing device. FIG. 4 is a partial cross-sectional view showing the microdispensing unit.

First, an outline of the microdispensing apparatus 1 to which the dispensing needle is attached will be described. A dispensing table 5 is provided on the table 3 of the microdispensing apparatus 1. A microplate 7 as a sample plate and a flat plate 9 as a dispensing plate are respectively mounted.

The microplate 7 has many pockets 7.
are integrally formed, and various sample solutions 11 of a biological sample solution and a multi-component substance solution which are dispensed and sampled on the flat plate 9 are stored in the respective pockets 7a. The flat plate 9 is made of a glass plate, a synthetic resin plate, absorbent paper, or the like. For example, twelve dispensing areas 9a (indicated by broken lines in FIG. 6) are sectioned at required intervals. . On each dispensing area 9a, an antibody or a reagent (not shown) for detecting the specific component in accordance with the sample solution 11 is immobilized. Then, on each dispensing area 9a, for example, 30 × 3
0 (900) sample solutions 11 are dispensed in a dot shape.

A washing / drying unit 13 is provided on the left side of the table 3 in the drawing, and the washing / drying unit 13 is divided by the dispensing unit 23 every time the dispensing unit 23 dispenses a sample solution 11 described later. After the injection needle 25 is subjected to ultrasonic cleaning, it is dried with hot air to remove the attached sample solution.

A support frame 15 is provided above the table 3, and each end of the movable frame 17 is connected to a short frame 15b in the longitudinal direction (X-axis direction) of the long frame 15a. It is movably supported in parallel. A feed screw and a timing belt (not shown) connected to a numerically controllable electric motor are connected to each end of the movable frame 17, and the movable frame 17 is moved in the X-axis direction by driving the electric motor. .

A slider 19 is supported on the support frame 15 so as to be movable in a direction (Y-axis direction) perpendicular to the direction of movement of the movable frame 17, and a feed screw connected to a numerically controllable electric motor is provided on the slider 19. And a timing belt (neither is shown). The movement of the slider 19 in the Y-axis direction is controlled by driving the electric motor. Note that the moving resolution of the movable frame 17 and the slider 19 is set to at least 0.05 to 0.1 mm, which is the distance between the sample solutions 11 dispensed into dots of a predetermined diameter on the flat plate 9.

The slider 19 is provided with an elevating member 21 such as an air cylinder having an axis in the vertical direction (Z-axis direction), and a dispensing unit 23 is attached to the elevating member 21. The dispensing unit 23 is moved up and down by the operation of the elevating member 21.

Mounting plate 23a in dispensing unit 23
A large number (for example, six) of dispensing needles 25 each having an axis in the vertical direction are provided at minute intervals (intervals between the center of the distal end surface and each other).
28 mm), the dispensing needles 25 are always urged downward along the axis by the elastic force of an elastic member 23c provided between the head and the cover 23b. You. Each dispensing needle 25 is made of a metal material such as stainless steel or a sintered material such as ceramics, and has a main body shaft portion 25a having a diameter of about 2 mm.
mm and a tapered tapered shape with a tip surface diameter of about 50 to 200 μm. A large-diameter lateral hole 25b extending in a direction perpendicular to the axis is formed at the tip of the main body shaft portion 25a.
A vertical groove 25c having a minute gap communicating with the groove b is formed.
The vertical groove 25c has an interval of 0.12 mm on the side of the horizontal hole 25b, and is set such that the lower portions are as close as possible.

The outer peripheral surface (tapered surface) of the distal end portion of the dispensing needle body 25 excluding the distal end surface is coated with a hydrophobic coating 25d (shown by a broken line in the figure). As the hydrophobic coating 25d, a fluorinated resin (a copolymer of tetrafluoroethylene and hexafluoropropylene, trade name: Teflon, DuPont), a silicon resin or a gold-plated film is suitable.

Next, the dispensing action of the dispensing needle 25 will be described. FIG. 5 is an explanatory diagram showing a state before dispensing. FIG.
FIG. 4 is an explanatory view showing a dispensing body. FIG. 7 is an explanatory view showing a dispensing state on a flat plate.

The dispensing unit 23 is operated by operating the elevating member 21.
The X-axis and Y-axis electric motors are respectively driven and controlled to move the dispensing unit 23 onto the pocket 7a into which the sample solution 11 to be detected is injected, and then move up and down. The dispensing unit 23 is moved downward by operating the member 21 to move the tip of each dispensing needle 25 to the sample solution 11.
Immerse yourself in. As a result, the sample solution 11 is placed in the side hole 25b.
And the inside of the vertical groove 25c.

Next, the elevating member 21 is operated to move the dispensing unit 23 upward to pull out the dispensing needle 25 from the inside of the sample solution 11 in the pocket 7a. The extra sample solution 11 attached to the outer peripheral surface is
The liquid is drained by 5d and returned into the pocket 7a. As a result, each dispensing needle 25 has a horizontal hole 25b and a vertical groove 25b.
Excess sample solution 1 other than sample solution 11 filled in c
1 is prevented from sticking.

Next, the dispensing unit 23 is moved above a predetermined dispensing area 9a on the flat plate 9 by controlling the driving of the electric motors for the X-axis and the Y-axis, respectively.
Is operated to move the dispensing unit 23 downward to bring the tip end surfaces of the respective dispensing needles 25 into contact with each other, so that the sample solution 11 filled in the lateral hole 25b becomes the sample solution 11 adhered on the flat plate 9.
Is drawn out through the vertical groove 25c due to the surface tension of the dispensing needle 25 and dispensed into a dot having a size substantially coincident with the tip surface of the dispensing needle 25. At this time, since the extra sample solution 11 does not adhere to the outer peripheral surface of the distal end portion of the dispensing needle 25 as described above, the extra sample solution 11 is prevented from attaching to the flat plate 9 and dispensing. It is possible to prevent the sample solutions 11 dispensed in a dot form from being mixed with each other by making the dot diameter of the sample solution 11 thus obtained substantially constant. Further, when the dispensing needle 25 comes into contact with the flat plate 9, an impact caused by the contact is applied to the elastic member 23.
c prevents damage to the distal end face of the dispensing needle 25 and the flat plate 9.

After the above dispensing operation, the elevating member 21 is operated to move the dispensing unit 23 upward to separate each dispensing needle 25 from the surface of the flat plate 9, and then the dispensing unit 23 is moved to the X-axis. Dispensing unit 2 by driving the electric motors for
After the needle 3 is moved, for example, by a distance corresponding to two rows of the dispensing needles 25, the elevating member 21 is operated again to move the dispensing unit 23 downward so that the tip end face of each dispensing needle 25 is The dispensed sample solution 11 is pressed against the dot row next to the dot row, and the sample solution 11 stored in the horizontal hole 25b is dispensed in a dot shape in the same manner as described above.

By repeating the above operation, each dispensing area 9a
On top, the sample solution 11 is dispensed into 900 dots. When the sample solution 11 filled in the lateral hole 25b is exhausted during the dispensing operation, the dispensing unit 23 is moved again onto the pocket 7a into which the sample solution 11 to be dispensed is injected, and the lateral hole 25b and The sample solution 11 is filled in the vertical groove 25c, and the dispensing operation is continued. When changing the sample solution 11 to be dispensed on the dispensing area 9a, the X-axis electric motor and the Y-axis electric motor are each driven and controlled to change the dispensing unit 2.
After moving 3 onto the washing / drying unit 13, the tip of each dispensing needle 25 is washed and dried, and then a different type of sample solution 11 is dispensed by the same operation as described above.

[0027]

As described above, according to the present invention, a predetermined amount of the sample solution stored in the vertical groove can be stably dispensed. Further, according to the present invention, the sample solution can be dispensed on the dispensing plate in a state where the sample solutions are surely separated from each other.
Further, the present invention can dispense a large number of samples with a small amount of a sample solution.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a dispensing needle body.

FIG. 2 is a longitudinal sectional view of a dispensing needle body.

FIG. 3 is a perspective view schematically showing a microdispensing device.

FIG. 4 is a partial cross-sectional view showing a minute dispensing unit.

FIG. 5 is an explanatory diagram showing a state before dispensing.

FIG. 6 is an explanatory view showing a dispensing body.

FIG. 7 is an explanatory view showing a dispensing state on a flat plate.

[Explanation of symbols]

Reference Signs List 1 microdispensing device, 7 microplate as sample plate, 9 flat plate as dispensing plate, 9a dispensing area, 11 sample solution, 25 dispensing needle, 25a main shaft, 25b horizontal hole, 25c vertical groove, 25d hydrophobic coating

Claims (5)

[Claims] 1. A dispensing needle is immersed in a pocket provided in a sample plate to hold a sample solution, and then the dispensing needle is brought into contact with the dispensing plate to form a dot-shaped sample solution. In the microdispensing device for dispensing, the tip of the dispensing needle has a tapered tapered shape in which the contact surface with the dispensing plate has a predetermined size, and communicates with the lateral hole penetrating in the direction perpendicular to the axis and the lateral hole. A dispensing needle for a microdispensing device, wherein a longitudinal groove of a minute gap extending in an axial direction and dividing a contact surface is formed. 2. A dispensing needle is immersed in a pocket provided in a sample plate to hold a sample solution, and then the dispensing needle is brought into contact with the dispensing plate to form a dot-shaped sample solution. In the microdispensing device for dispensing, the tip of the dispensing needle has a tapered tapered shape in which the contact surface with the dispensing plate has a predetermined size, and communicates with the lateral hole penetrating in the direction perpendicular to the axis and the lateral hole. A minute groove extending vertically in the axial direction and dividing the contact surface, and a hydrophobic coating is provided on the outer peripheral surface of the tip excluding the contact surface. Needle body for injection. 3. The dispensing needle according to claim 1, wherein the hydrophobic coating is made of a fluorinated resin. 4. The dispensing needle according to claim 1, wherein the hydrophobic coating is made of silicone resin. 5. A dispensing needle according to claim 1, wherein the hydrophobic coating is made of a gold thin film.