JPH0129567Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a detector for a particle detection device that allows particles such as blood cells and platelets suspended in a liquid to pass through micropores and detects them based on the difference in electrical impedance between the liquid and the particles. This is a detection system that prevents particle entrainment and return phenomena by ensuring that the particle suspension after passing through the particle detection micropores provided below the liquid surface quickly moves away from the vicinity of the micropores. The purpose is to provide equipment.

Particles such as red blood cells or platelets are suspended in physiological saline, etc., and the particle suspension is passed through micropores that are narrow enough to allow the particles to pass through, thereby determining the difference in electrical impedance between the particles and the liquid. In a particle counting device that detects particles based on, for example, when trying to detect platelets in a mixed solution of red blood cells and platelets, the red blood cells after passing through the micropore 1 are detected as shown in Fig. 1. A so-called entrainment phenomenon occurs in which the red blood cells floating in the vicinity of the micropores are caught up in the detection area 2, generating unnecessary pulses.The height of this pulse is the same as that of the platelets, so the apparent height of the platelets is The result is that the number increases. That is, as shown in Fig. 2, the height of pulse A caused by entrainment is the same as that of pulse B caused by platelets, so red blood cells caught in the detection area are also counted as platelets, and therefore the apparent value of platelets is The number increases. C is a pulse caused by red blood cells. For this reason, a double-structured detector that sucks up all the particle suspension after passing through the micropores is used to circulate the sucked liquid near the micropores, and a filter is installed in the middle to ensure that no particles are contained. Methods such as involving liquid have been proposed, but these have not been implemented due to problems with filter replacement, the structure of the circulation pump, and the method of quantifying the suspension passing through the micropores. In particular, the mixing of air bubbles significantly reduces the precision of quantitative determination, so the above circulation method is not common, considering that it is very difficult to remove air bubbles generated in the circulation path, or there are problems such as leakage.

The present invention was developed in view of the above points, and consists of fitting and fixing a detection pellet with fine holes in the lower part of a cylindrical detector body whose lower end is sealed.
A rectification pellet with a small hole bored through a space on the outside of this detection pellet is fixed to the outer surface of the detector body, a rectification liquid supply passage is connected to this space, and a rectification liquid supply passage is connected to this space. By arranging an electrode adjacent to the outlet side, unlike the conventional method of suctioning the sample, the sample is ejected while forming a double liquid flow with two pellets.
The object of the present invention is to provide a detector for a particle detection device that prevents the phenomenon of generating unnecessary pulses due to entrainment or return of particles.

The detector of the particle detection device of the present invention has micro holes 4 at the bottom of a cylindrical detector main body 3 whose lower end is sealed.
A rectifying pellet 8 having a small hole 7 bored through a space 6 on the outside of the detecting pellet 5 is fitted and fixed, and a rectifying pellet 8 having a small hole 7 bored therein is fixed to the outer surface of the detector main body 3. A thick-walled portion 12 is provided on the outer surface of the detector body above the detector pellet 5, and a rectifying liquid supply passage 10 is provided within the thick-walled portion for supplying a rectifying liquid having the same composition as the liquid from which particles are removed from the sample. This rectifying liquid supply passage is connected to the space 6, and an electrode 11 is arranged adjacent to the exit side of the fine hole in this space, so that positive pressure is applied to the sample in the detector body. The detector is configured such that the sample is ejected through the fine holes 4 of the detection pellet and the small holes 7 of the rectification pellet, and is characterized by having an electrode 16 and a sample discharge pipe 17 provided within the detector body.

Hereinafter, the configuration of the present invention will be explained based on embodiments shown in the drawings. 3 to 5 show one embodiment of the detector of the present invention. Reference numeral 3 denotes a cylindrical detector body with a sealed lower end, which is made of glass, synthetic resin, ceramic, or the like. A detection pellet 5 made of ruby, sapphire, ceramic, or the like is fitted in the lower part of the detector body 3, and has a fine hole 4 with a diameter of 30 to 200 μm for detecting particles.
Fixed. Further, a rectifying pellet 8 in which a small hole 7 is bored through a space 6 on the outside of the detecting pellet 5 is fixed to the outer surface of the detector main body.
Furthermore, a rectifying liquid supply passage 10 for supplying a rectifying liquid, such as physiological saline, which is a liquid having the same composition as the liquid from which particles are removed from the particle suspension, is connected to this space 6, and This space 6
An electrode 11 is disposed adjacent to the exit side of the fine hole 4 . Reference numeral 12 denotes a thick part provided on the outer surface of the detector main body 3 above the detection pellet 5;
The rectifying liquid supply passage 10 is provided within the rectifying liquid supply passage 10 . Note that a pipe or the like may be used as the rectifying liquid supply passage and connected to the space 6 from outside the detector main body 3. Reference numeral 13 is a line connected to the electrode 11, and reference numeral 14 is a fixing collar provided on the upper part of the detector main body 3. Note that the inside of the detector main body 3 is connected to a liquid metering device, a sample supply device, and a sample discharge device that are connected to a pressure source, although not shown.

In the detector of the present invention configured as described above, at the time of measurement, a suspension of particles is first introduced into the detector body 3 from the sample supply device, and the inside of the detector body 3 is filled. On the other hand, the rectifying liquid supply passage 1
0, and the space 6 between the detection pellet and the rectification pellet is filled under some pressure with a rectification liquid 15, such as physiological saline used for particle suspension. Next, positive pressure is applied from the liquid quantitative device into the detector body 3, and the sample is ejected through the fine holes 4 of the detection pellet and the small holes 7 of the rectifying pellet, and at the same time, the physiological saline is also ejected to surround the sample. do. Detector body 3
An internal electrode 16 (ground side) is provided inside, and particles are detected based on the change in electrical impedance between the particles and the electrode 11 (hot side) when they pass through the micropores 4. . After measurement, the sample discharge pipe 1 inserted into the detector body 3
7, the sample is discharged to the outside.

As explained above, the detector of the present invention ejects the sample that has passed through the micropores to the outside while being surrounded by a liquid that does not contain particles, so there is no phenomenon of particle entrainment or return. Therefore, since unnecessary pulses due to these phenomena are not generated, it has the effect of allowing accurate particle counting measurements, and is particularly useful for classifying and counting two types of particles, large and small, such as red blood cells and platelets. suitable for In addition, since it is only necessary to eject the sample inside the detector body, the amount of sample required is minimal.Since both the detection pellet and the rectification pellet are fixed to the detector body, it is necessary to align the two holes. It has the advantage of being easy to use and having a simple configuration.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional explanatory diagram showing a state in which an entrainment phenomenon occurs near a microhole in a conventional detector, Fig. 2 is an explanatory diagram of a pulse signal in the state shown in Fig. 1, and Fig. 3 4 is a front view showing one embodiment of the detector of the present invention, and FIG. 4 is A-A in FIG. 3.
The line sectional view, FIG. 5, is an enlarged view of the portion surrounded by a chain line circle in FIG. 4. 1... Fine hole, 2... Detection area, 3... Detector body, 4... Fine hole, 5... Detection pellet, 6
... Space, 7 ... Small hole, 8 ... Rectification pellet, 10 ... Rectification liquid supply passage, 11 ... Electrode, 12 ... Thick wall section, 13 ... Line, 14 ... Flange section, 15... Rectifying liquid, 16... Internal electrode, 1
7...Sample discharge pipe.

Claims (1)

[Scope of utility model registration request] A detection pellet with a microscopic hole was inserted and fixed in the lower part of the cylindrical detector body whose lower end was sealed, and a small hole was formed through the space on the outside of the detection pellet. A rectifying pellet is fixed to the outer surface of the detector body, a thick part is provided on the outer surface of the detector body above the detector pellet, and a rectifying liquid with the same composition as the liquid from which particles are removed from the sample is placed in this thick wall part. A rectifying liquid supply passage is provided for supplying the rectifying liquid, and this rectifying liquid supply passage is connected to the space, and an electrode is disposed adjacent to the exit side of the fine hole in this space, and the rectifying liquid supply passage is connected to the space. The detector is configured such that a positive pressure is applied to the sample and the sample is ejected through the fine holes of the detection pellet and the small holes of the rectification pellet, and is characterized by having an electrode and a sample discharge pipe inside the detector body. Detector of particle detection equipment.