Sheath flow impedance counting device and detection method

Abstract

The present invention discloses a sheath flow impedance counting device and a detection method. The sheath flow impedance counting device includes a pre-sheath flow cell and a post-sheath flow cell. The pre-sheath flow cell and the post-sheath flow cell are connected through a counting hole to form a particle path. A pre-cell electrode, a sample needle, a sheath liquid inlet, and a pre-cell flushing inlet are provided on the pre-sheath flow cell. The sample needle is used to transport a sample liquid into the pre-sheath flow cell. A post-cell electrode, a post-cell flushing inlet, a post-cell flushing outlet, and a sample waste liquid collection tube are provided on the post-sheath flow cell. The pre-cell electrode and the post-cell electrode together form a current loop for particle detection. The pre-cell flushing inlet and the post-cell flushing inlet both face the counting hole. The post-cell electrode is a sheet-like structure, and the sheet-like structure of the post-cell electrode is in a vertical plane. The post-cell flushing inlet is located below the X horizontal plane passing through the central axis of the counting hole. The sheath flow impedance counting device of the present invention is convenient for flushing, and can avoid bubbles generated during post-cell flushing from hiding in the dead corners of the electrode sheet.

Description

Technical Field

[0001] The present invention relates to the field of sheath flow impedance counting, and particularly to a sheath flow impedance counting device and a detection method. Background Art

[0002] The principle of sheath flow resistance impedance counting is to make the particles to be measured suspended in the electrolyte pass through a small hole (gem hole) one by one. On both sides of this small hole, an electrode (one positive electrode and one negative electrode) is installed. The positive and negative electrodes are electrically connected through the electrolyte before and after the small hole (gem hole) to form a constant current source. When the particles to be measured pass through the small hole, the overall conductivity of the electrolyte will change, thereby causing a change in resistance and generating a corresponding voltage pulse signal. The sheath flow impedance backpool electrode (positive electrode) generally uses a platinum sheet or a platinum wire. When using a platinum wire, the high-voltage burning function can be realized. The high-voltage burning can clean the residual protein and keep the gem hole unobstructed. When not considering the burning function, a platinum sheet is selected as the positive electrode.

[0003] The current sheath flow impedance counting device has the problem that it is not easy to be rinsed clean, which affects subsequent detection. Moreover, the sheath flow impedance backpool electrode is generally installed in the form of a platinum sheet. If the installation position is improper, it is easy to cause the bubbles generated during the backpool rinsing to hide in the dead corner of the electrode sheet. At the same time, it will also block the fluid flow direction, reduce the backpool rinsing ability, and reduce the accuracy of the sheath flow impedance detection result.

[0004] In view of this, it is necessary to provide a sheath flow impedance counting device and a detection method to solve or at least alleviate the above defects. Summary of the Invention

[0005] In order to solve the existing technical problems, the present invention provides a sheath flow impedance counting device that is easy to rinse.

[0006] To achieve the above object, the technical solution of the embodiment of the present invention is realized as follows:

[0007] A sheath flow impedance counting device includes a sheath flow front pool and a sheath flow back pool. The sheath flow front pool and the sheath flow back pool are connected through a counting hole to form a particle path. The sheath flow front pool is provided with a front pool electrode, a sample needle, a sheath liquid inlet, and a front pool rinsing inlet. The sample needle is used to transport the sample liquid into the sheath flow front pool. The sheath flow back pool is provided with a back pool electrode, a back pool rinsing inlet, a back pool rinsing outlet, and a sample waste liquid collection tube. The sample waste liquid collection tube is used to collect the sample waste liquid. The front pool electrode and the back pool electrode jointly form a current loop for particle detection. The front pool rinsing inlet and the back pool rinsing inlet both face the counting hole. The back pool electrode is a sheet-like structure, and the sheet-like structure of the back pool electrode is in a vertical plane. The back pool rinsing inlet is located below the X horizontal plane passing through the central axis of the counting hole.

[0008] Preferably, the post-pool flushing inlet is located below the post-pool electrode, and the post-pool flushing outlet is located above the post-pool electrode.

[0009] Preferably, the post-pool flushing inlet and the post-pool flushing outlet are located in the same vertical plane.

[0010] Preferably, the central axis of the post-pool flushing inlet is set at a preset angle with respect to the X horizontal plane, and the central axis of the post-pool flushing outlet is perpendicular to the X horizontal plane.

[0011] Preferably, the pre-pool flushing inlet and the sheath fluid inlet are located in the same vertical plane.

[0012] Preferably, the central axis of the pre-pool flushing inlet is set at a preset angle with respect to the X horizontal plane, and the central axis of the sheath fluid inlet is perpendicular to the X horizontal plane.

[0013] Preferably, the pre-pool flushing inlet and the post-pool flushing inlet are symmetrically arranged with respect to the vertical plane where the counting hole is located, and / or the sheath fluid inlet and the post-pool flushing outlet are symmetrically arranged with respect to the vertical plane where the counting hole is located.

[0014] Preferably, the inner wall of the pre-sheath pool near the counting hole is conical, and / or the inner wall of the post-sheath pool near the counting hole is conical.

[0015] In addition, the present invention also provides a detection method applied to the sheath flow impedance counting device as described above. The detection method includes the following steps:

[0016] Send the sample liquid into the pre-sheath pool through the sample needle;

[0017] Send the sheath fluid into the pre-sheath pool through the sheath fluid inlet. The sheath flow wraps the particles in the sample liquid so that they pass through the counting hole one by one and generate electrical signals;

[0018] Obtain the number and volume information of the sample particles according to the statistical analysis of the electrical signals.

[0019] Preferably, the detection method includes the following steps:

[0020] The pre-pool flushing liquid enters the pre-sheath pool through the pre-pool flushing inlet and flushes the counting hole, and flows upward and discharges from the sheath fluid inlet. The post-pool flushing liquid enters the post-sheath pool through the post-pool flushing inlet and flushes the counting hole, and flows upward and discharges from the post-pool flushing outlet.

[0021] In the above embodiments of the present application, the sheath flow impedance counting device includes a pre-sheath flow cell and a post-sheath flow cell. The pre-sheath flow cell and the post-sheath flow cell are connected through a counting hole to form a particle passage, and the sample particles in the pre-sheath flow cell can flow into the post-sheath flow cell through the counting hole. A pre-cell electrode, a sample needle, a sheath liquid inlet, and a pre-cell flushing inlet are provided on the pre-sheath flow cell, and a post-cell electrode, a post-cell flushing inlet, a post-cell flushing outlet, and a sample waste liquid collection tube are provided on the post-sheath flow cell. The sample particles are introduced into the pre-sheath flow cell through the sample needle, and the sample particles enter the post-sheath flow cell through the counting hole under the wrapping of the pre-sheath liquid, and then are discharged out of the post-sheath flow cell through the sample waste liquid collection tube. When the sample particles pass through the counting hole, the overall conductivity of the electrolyte will change, thereby causing a change in resistance and generating a corresponding voltage pulse signal. The pre-cell flushing inlet and the post-cell flushing inlet both face the counting hole, so that the pre-cell flushing liquid injected into the pre-sheath flow cell through the pre-cell flushing inlet can flush the side of the counting hole close to the pre-sheath flow cell, and at the same time, the post-cell flushing liquid injected into the post-sheath flow cell through the post-cell flushing inlet can flush the side of the counting hole close to the post-sheath flow cell. In addition, in order to avoid the situation of air bubbles hiding in the post-cell electrode, the post-cell electrode is a sheet structure, the sheet structure of the post-cell electrode is in a vertical plane, and the post-cell flushing inlet is located below the X horizontal plane passing through the central axis of the counting hole. Since the post-cell flushing liquid flows from bottom to top after entering the post-sheath flow cell, and the sheet structure of the post-cell electrode is in a vertical plane, it can make the fluid in the post-sheath flow cell have the least resistance and the smallest dead angle where air bubbles can hide, thereby avoiding the adhesion or storage of air bubbles at the post-cell electrode and affecting the accuracy of the sheath flow impedance detection result. Description of the Drawings

[0022] Figure 1 It is a front view sectional view of the sheath flow impedance counting device in the embodiment of the present application.

[0023] The realization, functional characteristics, and advantages of the object of the present invention will be further described in conjunction with the embodiments with reference to the drawings.

[0024] Explanation of the Reference Numerals in the Drawings:

[0025] 100 - pre-sheath flow cell, 110 - pre-cell electrode, 120 - sample needle, 130 - pre-cell flushing inlet;

[0026] 200 - post-sheath flow cell, 210 - post-cell electrode, 220 - post-cell flushing inlet, 230 - post-cell flushing outlet, 240 - sample waste liquid collection tube;

[0027] 300 - counting hole. Detailed Embodiments

[0028] The technical solution of the present invention will be further elaborated in detail below in conjunction with the accompanying drawings of the specification and specific embodiments. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. In the following description, the expression "some embodiments" describes a subset of all possible embodiments. However, it should be understood that "some embodiments" may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0029] It should be further noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "inner", "outer", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only implementation.

[0030] Please refer to Figure 1, an embodiment of the present application provides a sheath flow impedance counting device, including a counting cell and a counting circuit connected to the counting cell. The counting cell includes a pre-sheath cell 100 and a post-sheath cell 200. The pre-sheath cell 100 and the post-sheath cell 200 are connected through a counting hole 300 to form a particle passage. A pre-cell electrode 110, a sample needle 120, a sheath fluid inlet, and a pre-cell flushing inlet 130 are provided on the pre-sheath cell 100. The pre-cell electrode 110 is used to connect to the negative electrode of a constant current source, thereby connecting the pre-sheath fluid to the negative electrode. At the same time, the pre-cell electrode 110 can also be used as an input port for the pre-sheath fluid, that is, the sheath fluid inlet is directly provided at the port of the pre-cell electrode 110. The sample needle 120 is used to transport a sample particle suspension into the pre-sheath cell 100. A post-cell electrode 210, a post-cell flushing inlet 220, a post-cell flushing outlet 230, and a sample waste liquid collection tube 240 are provided on the post-sheath cell 200. The post-cell electrode 210 is used to connect to the positive electrode of a constant current source, thereby connecting the post-sheath fluid to the positive electrode. The post-cell flushing inlet 220 is used to introduce a diluted sheath fluid to flush the counting hole 300 at the post-sheath cell 200. The post-cell flushing outlet 230 is used to discharge the flushing waste liquid or air bubbles from the post-sheath cell 200. The nozzle of the sample waste liquid collection tube 240 faces the counting hole 300, so that the particle sample flow passing through the counting hole 300 enters the sample waste liquid collection tube 240, preventing particles from flowing back to the counting hole 300 and interfering with particle counting. Both the pre-cell electrode 110 and the post-cell electrode 210 are electrically connected to the counting circuit. Both the pre-cell flushing inlet 130 and the post-cell flushing inlet 220 face the counting hole 300. The post-cell electrode 210 is in a sheet structure, and the sheet structure of the post-cell electrode 210 is in a vertical plane. The post-cell flushing inlet 220 is located below the X horizontal plane passing through the central axis of the counting hole 300.

[0031] Wherein, the direction passing through the central axis of the counting hole 300 on the figure and perpendicular to the paper surface is the X horizontal plane, and the plane perpendicular to the X horizontal plane and parallel to the central axis of the counting hole 300 is the vertical plane.

[0032] Among them, inner cavities for the sheath fluid or the flushing fluid to flow are formed in both the front sheath fluid chamber 100 and the rear sheath fluid chamber 200. Both the front chamber flushing inlet 130 and the rear chamber flushing inlet 220 face the counting hole 300, so that the front chamber flushing fluid injected into the front sheath fluid chamber 100 through the front chamber flushing inlet 130 can flush the side of the counting hole 300 close to the front sheath fluid chamber 100, and at the same time, the rear chamber flushing fluid injected into the rear sheath fluid chamber 200 through the rear chamber flushing inlet 220 can flush the side of the counting hole 300 close to the rear sheath fluid chamber 200. The front chamber flushing fluid and the rear chamber flushing fluid can be diluted sheath fluid, and by flushing the counting hole 300 after each detection, the accuracy of the next detection can be ensured. After the front chamber flushing fluid finishes flushing the counting hole 300, it flows out from the sheath fluid inlet, and after the rear chamber flushing fluid finishes flushing the counting hole 300, it flows out from the rear chamber flushing outlet 230.

[0033] In the above embodiments of the present application, the counting cell includes a pre-sheath flow cell 100 and a post-sheath flow cell 200. The pre-sheath flow cell 100 and the post-sheath flow cell 200 are connected through a counting hole 300 to form a particle passage. The sample particles in the pre-sheath flow cell 100 can flow into the post-sheath flow cell 200 through the counting hole 300. A pre-cell electrode 110 and a sample needle 120 are provided on the pre-sheath flow cell 100, and a post-cell electrode 210, a post-cell flushing inlet 220, a post-cell flushing outlet 230, and a sample waste liquid collection tube 240 are provided on the post-sheath flow cell 200. The sample particles are introduced into the pre-sheath flow cell 100 through the sample needle 120. The sample particles enter the post-sheath flow cell 200 through the counting hole 300 under the wrapping of the pre-cell sheath fluid, and then are discharged outside the post-sheath flow cell 200 through the sample waste liquid collection tube 240. When the sample particles pass through the counting hole 300, the overall conductivity of the electrolyte changes, thereby causing a change in resistance and generating a corresponding voltage pulse signal, which is acquired by the counting circuit. The pre-cell flushing inlet 130 and the post-cell flushing inlet 220 both face the counting hole 300, so that the pre-cell flushing liquid can better flush the side of the counting hole 300 close to the pre-sheath flow cell 100, and at the same time the post-cell flushing liquid can better flush the side of the counting hole close to the post-sheath flow cell 200. In addition, in order to avoid the situation that air bubbles are hidden in the post-cell electrode 210, the post-cell electrode 210 is a sheet structure, the sheet structure of the post-cell electrode 210 is in a vertical plane, and the post-cell flushing inlet 220 is located below the X horizontal plane passing through the central axis of the counting hole 300. The post-cell flushing liquid passes through the post-cell flushing inlet 220 and flows upward toward the counting hole 300 and is discharged from the post-cell flushing outlet 230. The fluid has a shearing flushing effect on the vertically arranged post-cell electrode 210, and the sheet structure of the post-cell electrode 210 being in a vertical plane can minimize the resistance of the fluid in the post-sheath flow cell and the dead corners where air bubbles can be hidden, thereby avoiding the adhesion or storage of air bubbles at the post-cell electrode and affecting the accuracy of the sheath flow impedance detection result.

[0034] As a preferred embodiment of the present invention, the post-cell flushing inlet 220 is located below the post-cell electrode 210, and the post-cell flushing outlet 230 is located above the post-cell electrode 210. The post-cell flushing liquid flows through the vertically arranged post-cell electrode 210 from bottom to top, producing a shearing flushing effect on the post-cell electrode 210. Further, the post-cell flushing inlet and the post-cell flushing outlet can be located in the same vertical plane. Since the post-cell flushing inlet 220 has a guiding effect on the flow direction of the post-cell flushing liquid, by setting the post-cell electrode 210 and the post-cell flushing inlet 220 in the same vertical plane, the fluid resistance in the post-sheath flow cell can be further reduced.

[0035] As a specific embodiment of the present invention, the central axis of the rear cell flushing inlet 220 is set at a preset angle with respect to the X horizontal plane, and the central axis of the rear cell flushing outlet 230 is perpendicular to the X horizontal plane. In this embodiment, the central line of the rear cell flushing inlet 220 forms a preset angle with the central axis of the counting hole 300. The preset angle can be 20 - 80°, preferably 45°, 60°; wherein, the central line of the rear cell flushing inlet 220 can be set at any position on the rotating surface below the central axis of the counting cell. The central axis of the rear cell flushing outlet 230 is perpendicular to the X horizontal plane to facilitate the discharge of bubbles.

[0036] Similarly, the front cell flushing inlet and the sheath fluid inlet can also be located in the same vertical plane. The sheath fluid inlet, as the outlet of the front cell sheath fluid, being in the same vertical plane as the front cell flushing inlet can reduce the fluid resistance in the sheath flow front cell. Further, the central axis of the front cell flushing inlet 130 is set at a preset angle with respect to the X horizontal plane, and the central axis of the sheath fluid inlet is perpendicular to the X horizontal plane. The preset angle can be 20 - 80°, preferably 45°, 60°. Preferably, to ensure the symmetry of the structure, the front cell flushing inlet 130 and the rear cell flushing inlet 220 are symmetrically arranged with respect to the vertical plane where the counting hole 300 is located, and / or the sheath fluid inlet and the rear cell flushing outlet 230 are symmetrically arranged with respect to the vertical plane where the counting hole 300 is located.

[0037] Further, the rear cell electrode 210 and the sample waste liquid collection tube 240 are spaced apart from each other and adjacent. The vertical plane where the rear cell electrode 210 is located is parallel to the central axis of the sample waste liquid collection tube 240, which is beneficial to reducing the overall fluid resistance in the sheath flow rear cell 200.

[0038] Preferably, the axes of the sample needle 120 and the sample waste liquid collection tube 240 are both collinear with the axis of the counting hole 300. The collinear arrangement of the axis of the sample needle 120 and the axis of the counting hole 300 facilitates the smooth entry of the sample particles coming out of the sample needle 120 into the counting hole 300, and the outlet of the sample needle 120 is close to the counting hole 300. The sheath fluid in the sheath flow front cell 100 and the sheath flow rear cell 200 is a conductive liquid source without particles. The pressure of the front cell sheath fluid is equal to the pressure at the outlet of the sample flow in the sample needle 120, and the pressure of the rear cell sheath fluid is less than the pressure of the front cell sheath fluid, so that the front cell sheath fluid wraps the sample flow and flows into the rear cell sheath fluid. At the same time, the collinear arrangement of the axis of the sample waste liquid collection tube 240 and the axis of the counting hole 300 enables the particle sample flow passing through the counting hole 300 to smoothly enter the sample waste liquid collection tube 240, avoiding the backflow of particles to the counting hole 300 and interfering with particle counting.

[0039] As a specific embodiment of the present invention, one end of the rear - pool electrode 210 is located inside the sheath - flow rear pool 200 and contacts the sheath fluid in the cavity of the sheath - flow rear pool 200, and the other end of the rear - pool electrode 210 is located outside the sheath - flow rear pool 200 to connect to a constant - current source. The rear - pool electrode 210 can be fixed on the sheath - flow rear pool 200 through an electrode mounting hole or integrally provided with the sheath - flow rear pool 200.

[0040] Further, the counting hole 300 is formed in an artificial ruby sheet, and both the inner diameter and the depth of the counting hole 300 are less than 100 microns. The artificial ruby sheet is installed between the sheath - flow front pool 100 and the sheath - flow rear pool 200. The sample needle 120 is provided with a through - hole along the axial direction, thereby providing a passage for injecting sample particles into the sheath - flow front pool 100. There are two inlets on the sheath - flow front pool 100 leading to the inside of the sheath - flow front pool 100, one is the sample needle 120, and the other is the front - sheath - fluid inlet.

[0041] Preferably, the material of the rear - pool electrode 210 is platinum, and / or the material of the front - pool electrode 110 is platinum. The rear - pool electrode 210 needs to be a conductive material to play the role of electrode conduction. Among them, the front - pool electrode and the rear - pool electrode are made of platinum or other metal conductive materials with stable chemical properties and not prone to electrochemical corrosion. Further, both the sheath - flow front pool 100 and the sheath - flow rear pool 200 are made of insulating materials.

[0042] Preferably, the inner wall of the sheath - flow front pool 100 near the counting hole 300 is conical, and / or the inner wall of the sheath - flow rear pool 200 near the counting hole 300 is conical. The conical shape of the sheath - flow front pool 100 near the counting hole 300 can make the flow rate faster near the counting hole 300, and at the same time guide the sample flow towards the counting hole 300. When the sample liquid in the sheath - flow front pool 100 approaches the counting hole 300, its width will be gradually compressed, and at the same time, the distance between the sample particles in the sample liquid will also be gradually elongated. The front - pool sheath flow formed by the front - pool sheath fluid wraps the particles in the sample liquid and passes through the counting hole 300 one by one, and is discharged from the sample waste - liquid collection tube 240 of the sheath - flow rear pool 200. The conical shape of the sheath - flow rear pool 200 near the counting hole 300 has a similar effect.

[0043] In addition, the present invention also provides a detection method, which is applied to the sheath flow impedance counting device as described above. The sheath flow impedance counting device may further include a sample liquid syringe, a front chamber sheath liquid syringe, a front chamber flushing syringe, and a rear chamber flushing syringe; the sample liquid syringe is connected to the input end of the sample needle 120, the front chamber sheath liquid syringe is connected to the sheath liquid inlet (at the port of the front chamber electrode 110), the front chamber flushing syringe is connected to the front chamber flushing inlet 130, and the rear chamber flushing syringe is connected to the rear chamber flushing inlet 220; the detection method includes the following steps:

[0044] S10, controlling the sample liquid syringe to send the sample liquid through the sample needle 120 into the sheath flow front chamber 100, and at the same time controlling the front chamber sheath liquid syringe to send the front chamber sheath liquid through the sheath liquid inlet into the sheath flow front chamber 100, so that the front chamber sheath flow formed by the front chamber sheath liquid wraps the particles in the sample liquid and passes through the counting hole 300 one by one, and is discharged from the sample waste liquid collection tube 240 of the sheath flow rear chamber 200;

[0045] Among them, the sample liquid and the front chamber sheath liquid can obtain a boosting force by connecting an air pump, a liquid pump or other pressure sources. After the sample liquid and the front chamber sheath liquid are injected into the sheath flow front chamber 100, there is a flow rate difference between the sample liquid and the front chamber sheath liquid, forming a laminar flow. One end of the sheath flow front chamber 100 close to the counting hole 300 can be set as a conical fluid acceleration end, so that when the sample liquid in the sheath flow front chamber 100 is close to the counting hole 300, its width will be gradually compressed, and at the same time the distance between the sample particles in the sample liquid will also be gradually elongated. The front chamber sheath flow formed by the front chamber sheath liquid wraps the particles in the sample liquid and passes through the counting hole 300 one by one, and is discharged from the sample waste liquid collection tube 240 of the sheath flow rear chamber 200.

[0046] S20, the counting circuit calculates the data of the sample particles by obtaining the potential changes of the front chamber electrode 110 and the rear chamber electrode 210.

[0047] Since the front chamber electrode 110 and the rear chamber electrode 210 form a constant current source through the conduction of the electrolyte before and after the counting hole 300. When the sample particles pass through the counting hole 300, the overall conductivity of the electrolyte will change, thereby causing a change in resistance and generating a corresponding voltage pulse signal. After the counting circuit obtains the potential changes of the front chamber electrode 110 and the rear chamber electrode 210, the relevant data of the sample particles can be calculated through a preset algorithm program.

[0048] Further, the detection method may further include:

[0049] In S30, control the front-pool flushing syringe to allow the front-pool flushing liquid to enter the sheath-flow front pool 100 through the front-pool flushing inlet 130 to flush the side of the counting hole 300 close to the sheath-flow front pool 100; control the rear-pool flushing syringe to allow the rear-pool flushing liquid to enter the sheath-flow rear pool 200 through the rear-pool flushing inlet 220 to flush the side of the counting hole 300 close to the sheath-flow rear pool 200.

[0050] The front-pool flushing liquid enters the sheath-flow front pool 100 from the front-pool flushing inlet 130 and flushes the counting hole, and then flows upward and is discharged from the sheath liquid inlet. The rear-pool flushing liquid enters the sheath-flow rear pool 200 from the rear-pool flushing inlet 220 and flushes the counting hole 300, and then flows upward and is discharged from the rear-pool flushing outlet. The rear-pool flushing liquid passes through the rear-pool flushing inlet 220 towards the counting hole 300 and flows upward and is discharged from the rear-pool flushing outlet 230. The fluid has a shearing flushing effect relative to the vertically arranged rear-pool electrode 210, and the sheet structure of the rear-pool electrode 210 in the vertical plane can minimize the resistance of the fluid in the sheath-flow rear pool and the dead corners where air bubbles can hide, thereby preventing air bubbles from adhering to or being stored at the rear-pool electrode and affecting the cleaning ability of the sheath-flow rear pool. The front-pool flushing liquid and the rear-pool flushing liquid can be diluted sheath liquid. After each detection, the counting hole 300 is flushed to ensure the accuracy of the next detection.

[0051] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. The protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A sheath flow impedance counting device, comprising a pre-sheath flow cell and a post-sheath flow cell, wherein the pre-sheath flow cell and the post-sheath flow cell are connected through a counting hole to form a particle passageway, characterized in that, A front-pool electrode, a sample needle, a sheath liquid inlet, and a front-pool flushing inlet are provided on the sheath-flow front pool. The sample needle is used to deliver sample liquid into the sheath-flow front pool. A rear-pool electrode, a rear-pool flushing inlet, a rear-pool flushing outlet, and a sample waste liquid collection tube are provided on the sheath-flow rear pool. The sample waste liquid collection tube is used to collect sample waste liquid. The front-pool electrode and the rear-pool electrode together form a current loop for particle detection. Both the front-pool flushing inlet and the rear-pool flushing inlet face the counting hole. The rear-pool electrode is in a sheet structure. The sheet structure of the rear-pool electrode and the rear-pool flushing inlet are in the same vertical plane. The rear-pool flushing inlet is below the X horizontal plane passing through the central axis of the counting hole. The rear-pool electrode and the sample waste liquid collection tube are spaced apart, and the vertical plane where the rear-pool electrode is located is parallel to the central axis of the sample waste liquid collection tube.

2. The sheath flow impedance counting device according to claim 1, wherein The rear-pool flushing inlet is below the rear-pool electrode, and the rear-pool flushing outlet is above the rear-pool electrode.

3. The sheath flow impedance counting device according to claim 2, wherein, The rear-pool flushing inlet and the rear-pool flushing outlet are in the same vertical plane.

4. The sheath flow impedance counting device according to claim 2, wherein The central axis of the rear-pool flushing inlet is set at a preset angle with respect to the X horizontal plane, and the central axis of the rear-pool flushing outlet is perpendicular to the X horizontal plane.

5. The sheath flow impedance counting device according to any one of claims 1 to 4, characterized in that, The front-pool flushing inlet and the sheath liquid inlet are in the same vertical plane.

6. The sheath flow impedance counting device according to any one of claims 1 to 4, characterized in that The central axis of the front-pool flushing inlet is set at a preset angle with respect to the X horizontal plane, and the central axis of the sheath liquid inlet is perpendicular to the X horizontal plane.

7. The sheath flow impedance counting device according to any one of claims 1 to 4, characterized in that The front-pool flushing inlet and the rear-pool flushing inlet are symmetrically arranged with respect to the vertical plane where the counting hole is located, and / or the sheath liquid inlet and the rear-pool flushing outlet are symmetrically arranged with respect to the vertical plane where the counting hole is located.

8. The sheath flow impedance counting device according to any one of claims 1 to 4, characterized in that, The inner wall of the sheath-flow front pool near the counting hole is conical, and / or the inner wall of the sheath-flow rear pool near the counting hole is conical.

9. A detection method, applied to the sheath flow impedance counting device according to any one of claims 1 to 8, characterized in that, The detection method includes the following steps: Feed the sample liquid into the sheath-flow front pool through the sample needle. Feed the sheath liquid into the sheath-flow front pool through the sheath liquid inlet. The sheath flow wraps the particles in the sample liquid and makes them pass through the counting hole one by one to generate an electrical signal. Obtain the quantity and volume information of the sample particles according to the statistical analysis of the electrical signal.

10. The detection method according to claim 9, wherein, The detection method includes the following steps: The front-pool flushing liquid enters the sheath-flow front pool from the front-pool flushing inlet and flushes the counting hole, and flows upward and discharges from the sheath liquid inlet. The rear-pool flushing liquid enters the sheath-flow rear pool from the rear-pool flushing inlet and flushes the counting hole, and flows upward and discharges from the rear-pool flushing outlet.

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