JPS59228147A - Particle measuring apparatus - Google Patents

Abstract

PURPOSE:To stabilize a flow path volume and optically measure, with a high accuracy, particles in a sample liquid within a short period of time by previously applying a predetermined pressure to the flow path for trickles of a sample suspension and for sheath flows of a clean fluid passing by the surroundings. CONSTITUTION:The blood is conveyed to a dilute blood tank 13b. A two-way valve 31 is opened and a measuring part 23 of a changeover valve 2 is actuated. Thereupon, a flow path 22 is communicated with flow paths 24 and 25 for an electrolyte 10, which electrolyte containing the dilute blood flows into an optical cell 26 from an inlet. Inside the optical cell 26, a pressurized electrolyte circulates from a pressurized electrolyte tank 27 through flow paths 29, 38 and is pressurized at a given pressure, whereby the electrolyte 10 flows at a stable flow rate from the inlet such as to promptly form sheath flows. The laser light from a light source 20 passes through, in the form of a thin luminous flux, the sheath flow portion inside the cell 26 and is absorbed by a blocker 19. However, the front scattering light which is diffused by blood cells is detected by an optical detector 12 and is then counted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a device for measuring particles such as blood cells floating in a liquid, and particularly to a device for measuring particles in a circulating solution.

[Background of the invention]

A device for measuring the number of particles contained in a circulating fluid can be used for various purposes, but for the time being, the most suitable example of this application is blood cell strength, so this will be explained. Conventional blood cell counting methods include the electrical resistance method and the light scattering method.

The measurement method using the electrical resistance method involves diluting a certain amount of blood with an electrolyte solution, stirring it, and uniformly dispersing it. After that, electrodes are installed on both sides of the pore of a detection cell with pores, and a constant current is applied. The diluted blood is passed through the pores by suction or pressure.

This diluted blood is blood diluted with an electrolyte solution as described above, and white blood cells, red blood cells, platelets, etc. are suspended in it, and when these pass through the pores, a predetermined resistance value changes. That is, the resistance value increases because the pores, which are current paths, are narrowed by blood cells. By extracting and counting this resistance change as a pulse, the number of blood cells floating in the solution can be counted.

On the other hand, in the light scattering method, light is irradiated from the side of an optical cell and the scattered light is detected by a detector such as a photomultiplier.

However, in order to detect only scattered light, the irradiated light is canted by an absorbing member called a blocker. This optical cell allows diluted blood to flow vertically. When blood diluted with an electrolyte solution is passed through such an optical cell by suction or pressure, the blood cells floating in the solution emit light. It is scattered and detected by a detector as a pulse signal. The number of blood cells can then be determined by counting the number of pulses.

However, in the conventional method described above, even if a sample is introduced into the detection cell of the resistance method or the optical cell of the light scattering method and counting is started, the counted value is low at the beginning of the flow of the sample liquid and gradually becomes a constant value. Therefore, counting was performed after a certain period of time had passed after the sample was introduced. As a result, the measurement time becomes long and the amount of blood used also increases.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a particle measuring device which can eliminate the drawbacks of the prior art described above, shorten measurement time, improve accuracy, and reduce the amount of sample liquid used.

[Summary of the invention]

The present invention is characterized in that the channel for supplying a transparent fluid and a sample liquid in which particles are suspended is configured in a predetermined manner.

[Embodiments of the invention]

FIG. 1 is a system diagram of a blood cell counter that is an embodiment of the present invention. This device uses the light scattering method, and the switching valve 1,
2 is for cutting the channel 15, 22 therein by moving it up and down, measuring a portion of the sample liquid, and switching it into another channel. The squeezing pump 3 squeezes the soft tube 4 with a roller, and transfers the liquid inside the soft tube 4 in the rotational direction of the roller. At this time, the blood in the blood tank 13a is sucked by the nozzle 11, and the blood in the flow path 15. Blood detector 14. Transfer by suction via the soft tube 4.

The Shirinhama pumps 5, 6.7 have a function of sucking up the electrolyte solution 10 contained in the electrolyte solution tank 9 and sending out a certain amount of it. The optical cell 26 is a so-called sheath-snow cell as shown in FIG. 4, and the electrolyte solution 10 is sent through a flow path 29, and diluted blood is sent through a flow path 25 to a central nozzle.

As a result, the diluted blood has an electrolyte flow sheath (/-
It becomes a narrow stream surrounded by water, and the laser beam is irradiated here. Note that the forward scattered light emitted from this irradiation point is detected by the photodetector 12, and the irradiation light is detected by the blocker 19.
It is absorbed by. Further, the thickness of the flow of diluted blood is determined by the flow rate ratio with the electrolyte solution, and can be arbitrarily selected.

In addition, 8 is a waste liquid tank, 13b is a diluted blood tank, 16° 23 is a measuring section in each of the switching valves 1 and 2, 17° and 18 are flow paths for the electrolyte solution 10, 20 is a laser light source, and 21 is a compressor. . Further, 24 and 25 are flow paths for electrolyte solution,
27 is a pressurized electrolyte tank containing the electrolyte solution 10.

Furthermore, 30° 31, 32, and 33 are two-way valves that open and close the respective flow passages, and 34.35 are three-way valves that switch the flow passages.

Next, the operation of this blood cell counter will be explained.

When blood is collected from a patient and a request for a blood cell count test is received, the blood is transferred into a blood collection tube containing a blood coagulant, stirred, and then set as a blood tank 13a. When the measurement start switch is pressed, the straining pump 3 is activated, and the nozzle 11 sucks blood and sends it to the blood detector 14 through the channel 15.

Next, when the operation of the squeezing pump 3 is stopped, the flow path 15 of the switching valve 1 is filled with blood, so the metering section 16 is activated to connect the flow path 15 with the electrolyte fluid flow path 17, 18 through the communication valve. The diluted blood is then transferred into the diluted blood tank 13b. In other words, diluted blood with a predetermined dilution degree has been obtained.

This diluted blood is agitated by the compressed air from the compressor 21 introduced through the two-way valve 30 and a predetermined pressure is applied to it, so when the two-way valve 31 is opened, the flow path 22 of the switching valve 2 is filled. do. Next, when the metering section 23 of the switching valve 2 is operated, the flow path 22 communicates with the flow paths 24 and 25 for the electrolyte solution. Note that the compressed air from the compressor 21 applies a predetermined pressure to the pressurized electrolyte liquid tank 27 via the two-way valve 33. Therefore, when the flow path switching device 34 is switched to communicate with the pressurized electrolyte tank 27, the electrolyte solution 10 is changed.

It naturally flows through the channels 24, 22, 25 and rises through the center of the optical cell 26. At this time, by also communicating the flow path switching device 35 as shown in the figure, the pressurized electrolyte solution 10 in the pressurized electrolyte tank 27 flows through the flow path 29, and the pressurized electrolyte solution 10 containing the diluted blood is It surrounds in a sheath and rises. In addition,
32 is a two-way valve that controls the flow in the optical cell 26, and the liquid flowing out from this valve is sent to the waste liquid tank 8.

Now, the above is the most important improvement of this embodiment, but to explain the conventional method, the compressor 21 and the pressurized electrolyte tank 27 are not provided, and the diluted blood in the flow path 22 is pumped by the cylinder pump 6. was extruded into the optical cell 26 through the flow path 25.

In addition, at this time, the Shirinkei pump 7 is also activated to drain the flow path 29.
The electrolyte solution 10 was caused to flow through the tube to form a sheath flow. However, with this method, it takes time for the electrolyte solution flow to stabilize due to the expansion of the flow path due to the pressure that overcomes the resistance of the flow path including the optical cell 26, and stable measurement values could not be obtained until several seconds had elapsed. . In order to improve this, the flow path 24,
Although a metal tube was used at 25 to prevent expansion, it was not possible to significantly improve the measurement of 8 degrees, and the workability was poor, resulting in an increase in assembly time.

In this embodiment, as described above, when the flow path 22 of the switching valve 2 is filled with diluted blood, the measuring section 23 moves to force-feed the diluted blood in the flow path 22. At this time, the pressurized electrolyte liquid flows from the pressurized electrolyte liquid tank 27 through the channels 29, , 38, and the inside of the optical cell 2G is pressurized to a constant pressure. In this way, the flow path system internal pumps 6 and 7 are driven simultaneously. Therefore, the electrolyte liquid 10 flows into the optical cell 26 from the liquid injection port 37 and the sample injection port 36 shown in FIG. 4, and a sheath-like flow with a stable flow rate can be rapidly created.

When the electrolyte solution is irradiated with a light beam, the scattered light is negligible, but when diluted blood passes through it, the blood cells floating in it scatter the light and generate a pulse-like signal. Therefore, by counting this pulsed signal, the number of blood cells can be determined. Note that since the magnitude of the pulse signal is proportional to the amount of scattered light and the size of the blood cells, the number of blood cells and the particle size distribution of the blood cells can be determined by analyzing the pulse height value. This measurement is determined from the results of measurement for 5 to 10 seconds.

FIG. 2 is an explanatory diagram of the operation of the switching valve shown in FIG. 1.

FIG. 2(a) shows a state in which the flow path 15 is connected to the blood flow path shown in FIG. Channel 17.18
and is sent to the diluted blood tank 13b.

FIG. 3 is an enlarged sectional view of the optical cell of FIG. 1.

The electrolyte solution entering through the diluted blood inlet 36 rises to the narrow upper end containing the diluted blood. The electrolyte solution that entered from the electrolyte solution inlet 37 so as to surround this also rises and flows out.

On the other hand, the laser beam from the light source 20 passes through the sheath-shaped flow part in the transparent optical cell 26 as a thin beam and passes through the blocker 1.
Absorbed by 9.

However, the forward scattered light scattered by the blood cells at the center of the sheath flow is detected by the photodetector 12.

FIG. 4 shows a detection curve of a conventional blood cell counter, and FIG. 5 shows a detection curve of the blood cell counter of this embodiment shown in FIG.

In the case of FIG. 4, the electrolyte flow to the optical cell 26 is provided by a cylinder pump 6.7, and no prepressure is applied to the electrolyte in advance. Therefore, since the electrolyte liquid flow passing through the light transmitting part of the optical cell 26 stabilized after about 5 seconds, measurement was started after about 8 seconds after confirming that the electrolyte flow had stabilized. On the other hand, in the case of the blood cell counter of this embodiment, since a pre-pressure is applied to the electrolyte solution as described above, the flow path and the volume inside the optical cell 26 are stable, and a steady flow is achieved within 1 second, resulting in a stable flow of blood cells. You can get the count. Therefore, measurement efficiency has been greatly improved compared to the conventional method. Please note that this blood cell counter was developed as an emergency testing device, so
The effect of being able to perform rapid measurements in this way is significant.

FIG. 6 is a control system diagram of the blood cell counter shown in FIG. 1. When a laboratory technician at a hospital sets the blood tank 13a shown in FIG.
Activate. This mechanism control section 41 includes switching valves 1, 2, .
Cylinder pumps 5, 6, 7. L pump 3 and two-way valves 30 to 33. Flow path switching devices 34, 35, etc. are electrically connected.

Next, the signal detected by the photodetector 12 is analyzed by a pulse height analyzer 42, and a printer 43 and a cathode ray tube (C
RT) 44 displays the blood cell count, particle size distribution value, etc. The computer 40 monitors each part, and when a malfunction occurs, it displays it on the CRT 44 and also generates an alarm.The blood cell counter of this embodiment has a diluted blood tank and a diluted blood tank for storing diluted blood. By pressurizing an electrolyte reservoir containing an electrolyte solution to pre-expand the flow path to the optical cell, and then activating the syringe pump to quickly obtain a stable sheath flow within the optical cell, The effect is that highly accurate measurement values can be obtained efficiently.

Although the above embodiment has been described using a blood cell counter as an example, it is generally applicable to measuring various particles in liquid.

〔Effect of the invention〕

The particle measuring device of the present invention has the effect of improving measurement accuracy, improving measurement efficiency, and reducing the amount of sample liquid.

[Brief Description of the Drawings] Figure 1 is a system diagram of a blood cell counter that is an embodiment of the present invention, Figure 2 is an explanatory diagram of the operation of the switching valve in Figure 1, and Figure 3 is an illustration of the operation of the switching valve in Figure 1.
Fig. 4 is a detection curve diagram of the conventional blood cell counter, Fig. 5 is a detection curve diagram of the blood cell counter shown in Fig. 1, and Fig. 6 is a control system of the blood cell counter shown in Fig. 1. It is a diagram. 1.2...Switching valve, 3...Stretching pump, 4...
Soft titanium use, 5, 6.7... Cylinder pump, 8... Waste liquid tank, 9... Electrolyte liquid tank, 10... Electrolyte liquid, 11
...-nozzle, 12... photodetector, 13a... blood tank, 13b... diluted blood tank, 14... blood detector,
15,17°18.22,24,25,28,2.9・
...Flow path, 16...Measuring section, 19...Blocker, 2
0...Laser light source, 21...Compressor, 23.
...Measuring part, 26...Optical cell, 27...Pressurized electrolyte liquid tank, 30-33...2-way valve, 34.35...Flow path switch (3-way valve), 36...Dilution Blood inlet, 37... Liquid inlet for electrolysis, 38... Outlet, 40. Computer, 41... Mechanism control unit, 42... Pulse height analyzer, 43... Printer, 44... 01M ”, 45...Control bus, 46...Start switch. Agent Patent attorney Hiroo Nagasaki (and 1 other person) No. Z (2) No. 30 $4 Figure f /θ ftfItl (#) $5 Month 5 10 Same #

Claims (1)

[Claims] 1. A sheath flow in which a clean fluid passes around a trickle of sample liquid in which particles are suspended, and an optical cell formed so that measurement light is transmitted across the sheath flow. In a particle measuring device having a syringe pump provided to allow the sample liquid and the fluid to pass through the optical cell, a predetermined prepressure is applied to the flow path for supplying the fluid and the sample liquid. A particle measuring device characterized in that it is configured to stabilize the volume of the flow path and operate the above-mentioned syringe pump.