CN115902268A - Microchip for platelet measurement and platelet measurement device using the same - Google Patents

Abstract

The present invention relates to a microchip for platelet testing, an external device fitted with the microchip, and a system for platelet testing including the microchip. Moreover, the present invention also relates to a method for detecting platelets using the microchip and/or the platelet detection system of the present invention.

Description

Microchip for platelet measurement and platelet measurement device using the same

Technical Field

The invention relates to the technical field of medical instruments, in particular to a microchip for platelet detection and a platelet detection device using the microchip.

Background

Platelets play an important role in many pathophysiological processes, such as hemostasis, atherosclerosis, thrombo-inflammation, and the like. Accordingly, accurate assessment of platelet aggregation function has important value in predicting bleeding and ischemic event risk, elucidating causes of blood coagulation dysfunction, selecting antiplatelet drugs, and the like. Although the end-point detection method based on indexes such as coagulation time (prothrombin time) is simple to operate and widely used, the end-point detection method can only be used for evaluating part of hemostasis processes and is far from the real physiological environment, so that postoperative bleeding and other phenomena often occur in detection based on the method although the indexes such as the coagulation time in the perioperative period are normal. In order to improve the detection effect, most of the platelet function detection methods applied in clinical and scientific research at the present stage are optical turbidimetry methods for inducing platelet aggregation by using an activating agent, but the methods have more defects, such as high dependence on professional inspectors, need of the assistance of central laboratory equipment such as a centrifuge and the like, incapability of evaluating the influence of other peripheral blood cell types on the platelet aggregation function, and the like. In addition, the optical turbidimetry is not high in timeliness due to factors such as the need of waiting for concentrated sample loading of samples; the inactivation speed of the platelets after being isolated is high, and the platelet function result measured by using blood which is collected and placed for hours is not accurate. The VerifyNow equipment developed based on the optical turbidimetry principle shortens the centrifugal process through the design of beads covered with fibrinogen, so that the miniaturization of an instrument is realized, but the equipment and a detection device thereof have complex structures and high prices, and cannot be widely popularized in clinic. And VerifyNow is designed to evaluate the effect of GPIIb-IIIa antagonists, but has insufficient sensitivity to aspirin, clopidogrel and other drugs. Moreover, clinical studies have shown that VerifyNow is not accurate enough even when used solely to evaluate GPIIb-IIIa antagonist effects.

Thromboelastography assesses the overall hemostatic function from thrombosis to lysis by monitoring the viscoelastic changes during clot formation. The method takes whole blood as a specimen, can provide an intuitive and complete blood agglutination generation, development and change process, but still has certain limitations, such as incapability of detecting platelet dysfunction (such as uremia patients) caused by abnormal interaction between platelets and vascular endothelium; the conventional thromboelastogram adopts thrombin as a platelet agonist, and if a patient receives antiplatelet treatment, the conventional thromboelastogram cannot reflect the blood coagulation function of the patient; there is currently no unified reference standard.

By measuring the change of electrical properties in the platelet aggregation process, the function of the platelets in whole blood can be detected without centrifugation, and the implanted electrode provides a reaction plane for the platelet aggregation process, is closer to the aggregation process of the platelets in vivo on damaged endothelium than an optical turbidimetry method, and is not influenced by blood chylation and the like with the influence of hyperlipidemia and the like on light passing rate. Electric impedance analysis of platelet aggregation process has been achieved by Multiplate. However, the existing product needs magnetic stirring, and the system is complex and large in size, so that the timeliness and the use convenience of platelet function analysis are difficult to effectively improve. Plateleworks counts unaggregated platelets in a sample by an electrical impedance counting method to analyze platelet aggregation function, but it cannot detect aspirin inhibition effect and has low clinical relevance.

The micro-fluidic technology has the characteristics of small sample consumption, high detection speed, miniaturized volume and the like. The invention designs and prepares a portable multi-channel microfluidic platelet analysis chip based on the principle of an electrical impedance method, realizes the integrated, automatic and portable platelet function analysis of 'sample input and result output', and can realize the rapid bedside detection of platelet functions.

[ reference documents ]

Panicia, R., priora, R., liotta, A.A. and Abbat, R., platlet function tests: a comparative review, vasc Health Risk Manag,11,133-148, doi.

2.van Werkum, J.W., et al, the use of The VerifyNow system to monitor anti latelteret therapy, a review of The current evaluation, plants, 19,479-488, doi.

3.Kereikes, D.J., et al, time core, magnitude, and relationship of platlet inhibition by abciximab, tifiban, epitification in substrates with independent agriculture subunit, am J Cardiol, 8978 zft 8978-395, doi.

Cardinal, D.C. and Flower, R.J., the electronic imaging meter: a novel device for assessing platelet behavior in blood, J Pharmacol Methods,3,135-158, doi.

Disclosure of Invention

Specifically, the technical problems in the prior art are solved by the following technical schemes:

1. a microchip for platelet testing, wherein said microchip comprises the following areas in communication with each other:

a sample inlet region 1, said sample inlet region 1 comprising a sample inlet 11 for adding a blood sample and one or more sample flow channels 12 connecting the sample inlet 11 with one or more storage chambers 21, respectively;

a reagent storage area 2, said reagent storage area 2 comprising one or more storage chambers 21 that can be used for storing solid reagents;

a mixing zone 3, said mixing zone 3 comprising one or more mixing flow channels for connecting said one or more storage chambers 21 with one or more detection chambers 41, respectively, and mixing said blood sample with said solid reagent therein;

a detection zone 4, said detection zone 4 comprising one or more detection chambers 41 for detecting platelets of said blood sample and a pair of detection electrodes 42 disposed in each detection chamber 41; and

-a sample outlet adapted to be connected to a fluid control means providing a negative pressure.

2. The microchip according to item 1, wherein the sample outlet is provided in the detection zone 4.

3. The microchip according to item 1, wherein the microchip further comprises a waste liquid zone 5, the sample outlet being provided in the waste liquid zone 5.

4. The microchip according to any one of items 1 to 3, wherein the number of the sample injection flow channel 12 is 2 to 8, preferably 3 to 6, and more preferably 4 to 5.

5. The microchip of item 4, wherein the width and length of each of the sample flow channels 12 are adapted to equalize the flow resistance of each flow channel.

6. The microchip of any of items 1-5, wherein one or more of the storage chambers 21 comprises a pre-embedded reagent, and wherein the blood sample is contacted and/or mixed with the reagent in the storage chamber 21.

7. The microchip of any one of items 1-6, wherein at least one of the storage chambers 21 does not include a pre-embedded reagent, which acts as a blank.

8. The microchip according to item 6 or 7, wherein the pre-embedded reagent is a reagent promoting blood coagulation, preferably selected from the group consisting of: arachidonic Acid (AA), adenosine Diphosphate (ADP), collagen (COL), thromboxane A2 (TXA 2), epinephrine (Adr), and 5-hydroxytryptamine (5-HT).

9. The microchip according to items 1 to 8, wherein the storage chamber 21 is a cylindrical or cubic chamber, preferably the storage chamber has a height of 0.1 to 5 mm, preferably the bottom surface area of the cylindrical chamber has a diameter of 1 to 10 mm or the bottom surface area of the cubic chamber has a length and/or width of 1 to 10 mm.

10. The microchip according to any one of items 1 to 9, wherein the mixing channel is a ring-shaped channel or an S-shaped channel having one or more turns, preferably the mixing channel has a height and/or width of 0.5 to 5 mm.

11. The microchip according to item 10, wherein the number of said folding back is 1 to 50, preferably 5 to 20, more preferably 10 to 15.

12. The microchip according to item 10 or 11, wherein each of the folded-back lengths is 0.5 to 20 mm, preferably 1 to 10 mm.

13. The microchip according to any one of items 1 to 12, wherein a plurality of baffles are provided in the mixing channel at an angle to the flow direction of the blood sample, preferably at an angle of 15 to 165 degrees, and preferably at an interval of 0.1 to 1 mm.

14. The microchip according to any one of items 1 to 9, wherein a protrusion is provided on the inner surface of the mixing channel, preferably the height and/or width of the protrusion is 10% to 90%, more preferably 20% to 80%, more preferably 30% to 70% of the height and/or width of the mixing channel.

15. The microchip according to any one of items 1 to 14, wherein the detection chamber 41 is a cylindrical or cubic chamber, preferably the detection chamber has a height of 0.1 to 5 mm, preferably the diameter of the bottom area of the cylindrical chamber is 0.5 to 10 mm or the length and/or width of the bottom area of the cubic chamber is 1 to 10 mm.

16. The microchip as defined in any one of claims 1 to 15, wherein magnetic beads are provided in the detection chamber 41, and the magnetic beads are capable of stirring the sample entering the detection chamber 41 by a magnetic field.

17. The microchip as defined in any one of items 1 to 16, wherein the detection electrode 42 is connected to an external detection circuit to detect an electrical signal for coagulation of the blood sample, preferably the electrical signal is an electrical impedance signal.

18. The microchip of any one of items 1-17, wherein the detection electrode 42 is a planar electrode, preferably the planar electrode has been modified with a modifying material, more preferably the modifying material is selected from the group consisting of: fibrinogen, prothrombin, bovine serum albumin, fibronectin and collagen.

19. The microchip of any one of items 1-18, wherein the waste liquid region is configured to have a volume that is not less than 50% of the volume of the blood sample.

20. The microchip of any one of items 1-19, wherein the surface of the microchip that is in contact with the blood sample has been modified with a surface modifying material.

21. The microchip of item 20, wherein the surface modifying material is a hydrophilic material, preferably a copolymer hydrogel surfactant, more preferably selected from the group consisting of: salicylic acid derivative, polyvinylpyrrolidone, polyvinyl alcohol, and nano TiO ₂ PEGMEM, APTES, 3-chloropropyltrichlorosilane, PEG, brij-35, tween-20, F127, F108, F68 and poly-hema.

22. The microchip according to any one of items 1 to 21, wherein a portion of the microchip other than the detection electrode is made of a material selected from the group consisting of: polydimethylsiloxane (PDMS), polymethylmethacrylate (PMMA), polycarbonate (PC), polypropylene (PP), polystyrene (PS), cyclic Olefin Copolymer (COC), polytetrafluoroethylene (PTFE), polyamide (PI), epoxy, polyurethane, silicon, and glass.

23. The microchip of any one of items 1-22, wherein the detection electrode is made of a material selected from the group consisting of: gold, platinum, carbon-based materials, silver paste, nickel, aluminum and copper, preferably the carbon-based materials are selected from the group consisting of: carbon nanotubes, graphene, and carbon paste.

24. The microchip of any one of items 1-23, wherein the overall dimensions of the microchip are (3-10) cm (0.2-2.0) cm.

25. The microchip of any one of items 1-24, wherein the microchip is capable of providing a result of a platelet test within 15 minutes, preferably within 10 minutes, more preferably within 5 minutes, after addition of a sample.

26. An external device adapted to the microchip of any of claims 1-25, the external device comprising:

an interface for assembling the microchip;

a fluid control device that connects to the sample outlet of the microchip and provides a negative pressure to the microchip when the microchip is mated with the external device through the interface;

an external detection circuit electrically connected to the detection electrode 42 to detect an electric signal when the blood sample is coagulated when the microchip is fitted to the external device through the interface; and

and the output device is used for displaying the detection result.

27. The external device of item 26, further comprising:

an element capable of providing a magnetic field outside the detection chamber 41 when the microchip is adapted to the external device through the interface.

28. A system for platelet testing, comprising:

(a) The microchip of any one of items 1-25; and

(b) The external device of claim 26 or 27,

wherein the microchip is adapted on the external device.

29. A method for platelet testing, comprising:

(a) Mounting a microchip according to any of items 1-25 on an external device of item 26 or 27, or providing a system according to item 28;

(b) Adding a blood sample to the sample inlet 11 of the sample inlet zone 1 of the microchip; and

(c) An output device in the external device reads the results of the platelet testing.

30. The method of item 29, further comprising:

before, after or simultaneously with step (b), a magnetic field is provided outside the detection chamber 41.

In order to make the technical scheme of the microchip for platelet detection according to the present invention more clear, the present invention will be further described with reference to the accompanying drawings and the detailed description.

Drawings

FIG. 1 is a schematic diagram of a platelet function test chip according to the present invention;

FIG. 2 is a schematic cross-sectional view of a platelet function test chip according to the present invention;

fig. 3 is a schematic cross-sectional view of a mixing channel in the platelet function test chip according to the present invention, wherein arrows indicate the flow direction of a blood sample, α indicates the included angle between a baffle and the flow direction of the sample, and d indicates the interval between baffles;

FIG. 4 is an enlarged view of the detection region of the platelet function detection chip according to the present invention;

FIG. 5 is a schematic diagram of the data analysis method of the platelet function test chip of the present invention, in which "ADP" is a platelet activator and "control" is a control, and the result obtained by the method can be represented by the difference between the areas under the electrical impedance curves of the two along with time.

Wherein the reference numerals are:

1-a sample inlet area, 11-a sample inlet and 12-a branch flow channel;

2-a reagent storage area, 21-a circular chamber, 22-a pipeline communicating the circular chamber with a sample inlet area, 23-a pipeline communicating the circular chamber with a mixing area;

3-mixing zone, 31-baffle; 32-mixing flow channel

4-detection zone, 41-detection chamber, 42-detection electrode, 43-electrode pad, 44-sample outlet.

Detailed Description

1. Microchip of the invention

In one aspect, the invention provides a platelet function detection chip, which is based on a microfluidic technology, and is designed by a micro-pipeline structure, so that clinical blood or plasma samples are efficiently mixed with reagents to activate platelets in the samples, and the platelet activation function is evaluated by monitoring and analyzing the electrical impedance of the samples in real time. The microfluidic chip is provided with a plurality of channels, can synchronously detect a plurality of platelet aggregation factors, and is provided with a control group on the chip.

In one embodiment, the microfluidic chip of the present invention comprises the following regions: a sample inlet zone, a reagent storage zone, a mixing zone, a detection zone, and a sample outlet. In one embodiment, the microfluidic chip of the present invention comprises regions that are interconnected. In one embodiment, the sample inlet region comprises a sample inlet for adding a blood sample and one or more sample flow channels connecting the sample inlet with one or more storage chambers, respectively. In one embodiment, the reagent storage region comprises one or more storage chambers that can be used to store solid reagents. In one embodiment, the mixing zone comprises one or more mixing flow channels for connecting the one or more storage chambers with one or more detection chambers, respectively, and mixing the blood sample with the solid reagent in the flow channels. In one embodiment, the detection zone includes one or more detection chambers for detecting platelets of the blood sample and a pair of detection electrodes disposed in each detection chamber. In one embodiment, the microfluidic chip of the present invention further comprises a sample outlet adapted to be connected to a fluid control device providing a negative pressure. In one embodiment, the sample outlet is disposed in the detection zone. In one embodiment, the microfluidic chip of the present invention further comprises a waste region, and the sample outlet is disposed in the waste region.

In one embodiment, after the sample enters the sample inlet region of the microfluidic chip of the present invention, the sample is split to one or more sample injection flow channels and flows through the reagent storage region, the mixing region and the detection region in sequence. In one embodiment, after the sample passes through the detection zone of the microfluidic chip of the present invention, the residual sample is collected in the waste zone.

In one embodiment, the sample inlet region comprises a plurality of sample flow channels to enable multi-channel simultaneous detection. In one embodiment, the number of sample injection flow channels is 2-8, preferably 3-6, more preferably 4-5. In one embodiment, the width and length of each of the sample flow channels are designed to be suitable for equalizing the flow resistance of each channel. In one embodiment, the sample enters the reagent storage region at the same time after entering each sample flow channel from the sample inlet.

In one embodiment, one or more of the storage chambers includes a pre-embedded reagent, and a blood sample is contacted and/or mixed with the pre-embedded reagent in the storage chamber. In one embodiment, at least one of the storage chambers does not include a pre-embedded reagent, which acts as a blank. In one embodiment, the pre-embedded agent is an agent that promotes blood clotting. In one embodiment, the pre-embedded agent is selected from the group consisting of: arachidonic Acid (AA), adenosine Diphosphate (ADP), collagen (COL), thromboxane A2 (TXA 2), epinephrine (Adr), and 5-hydroxytryptamine (5-HT). In one embodiment, the storage chamber is a cylindrical or cubic chamber. In one embodiment, the height of the storage chamber is 0.1 to 5 mm. In one embodiment, the diameter of the bottom area of the cylindrical chamber is 1-10 mm, or the length and/or width of the bottom area of the cubic chamber is 1-10 mm. In one embodiment, the inlet of the sample into the storage chamber and the outlet of the sample from the storage chamber are each located diagonally across the storage chamber, thereby promoting sufficient contact and mixing of the sample with the pre-embedded reagent so that the reagent is more uniformly dispersed in the sample. In one embodiment, the reagent in the chip preparation is embedded in the microchip reagent storage area.

In one embodiment, the mixing zone comprises a mixing flow channel that is an annular flow channel or an S-shaped long flow channel with one or more turns. In one embodiment, the height and/or width of the mixing channel is 0.5 to 5 mm. In one embodiment, the number of such foldovers is from 1 to 50, preferably from 5 to 20, more preferably from 10 to 15. In one embodiment, the length of each of said folds is in the range of 0.5 to 20 mm, preferably 1 to 10 mm. In one embodiment, a plurality of baffles which are arranged in the mixing flow channel and form an included angle with the flowing direction of the blood sample and are spaced from each other are arranged in the mixing flow channel. In one embodiment, the included angle α is from 15 ° to 165 °, preferably from 30 ° to 150 °, more preferably from 45 ° to 145 °, more preferably from 60 ° to 120 °. In one embodiment, the distance of separation is from 0.1 to 1 mm, preferably from 0.2 to 0.8 mm, more preferably from 0.3 to 0.5 mm. In one embodiment, the mixing channel is provided with protrusions on its inner surface. In one embodiment the height and/or width of the projections on the inner surface of the mixing channel is between 10% and 90%, more preferably between 20% and 80%, more preferably between 30% and 70%, more preferably between 40% and 60% of the height and/or width of said mixing channel.

In one embodiment, the detection zone comprises detection chambers that are cylindrical or cubic chambers, and in one embodiment, the detection chambers have a height of 0.1 to 5 mm. In one embodiment, the bottom area of the cylindrical chamber has a diameter of 0.5 to 10 mm. In one embodiment, the bottom area of the cubic chamber is 1-10 mm long and/or wide. In one embodiment, magnetic beads are disposed within the detection chamber, and are capable of agitating a sample entering the detection chamber via a magnetic field. In one embodiment, the bottom region of the detection chamber is provided with a pair of planar electrodes. In one embodiment, the planar electrode is connected to an external detection circuit via a wire to detect an electrical signal generated by coagulation of the blood sample. In one embodiment, the electrical signal is an electrical impedance signal. In one embodiment, the planar electrodes are connected to an external detection circuit via electrode pads by wires for real-time detection of electrical impedance signals of coagulation of the blood sample. In one embodiment, the planar electrode has been modified with a modifying material in order to accelerate platelet aggregation, improve electrical impedance detection, or increase the stability of the electrode. In one embodiment, the modifying material is selected from the group consisting of: fibrinogen, prothrombin, bovine serum albumin, fibronectin and collagen.

In one embodiment, the waste liquid region is a large integral chamber, and liquid in each channel can flow into the waste liquid region to be collected. In one embodiment, the waste zone is specifically sized according to the volume of the sample to be detected. In one embodiment, the volume of the waste liquid region is configured to be not less than 50% of the volume of the blood sample. In one embodiment, the waste liquid zone is provided with 1 outlet, the outlet and a micro pump fluid control device communication to provide the microchip with negative pressure, thereby the sample from the sample inlet to completely fill the detection zone and a small amount of liquid into the waste liquid zone.

In one embodiment, the surface of the microchip that contacts the blood sample has been modified with a surface modifying material. In one embodiment, the surface modifying material is a hydrophilic material. In one embodiment, the surface modifying material is a copolymer hydrogel surfactant. In one embodiment, the surface modifying material is selected from the group consisting of: salicylic acid derivative, polyvinylpyrrolidone, polyvinyl alcohol, and nano TiO ₂ PEGMEM, APTES, 3-chloropropyltrichlorosilane, PEG, brij-35, tween-20, F127, F108, F68, poly-hema.

In one embodiment, the microchip except for the detection electrode is made of a material selected from the group consisting of: polydimethylsiloxane (PDMS), polymethylmethacrylate (PMMA), polycarbonate (PC), polypropylene (PP), polystyrene (PS), cyclic Olefin Copolymer (COC), polytetrafluoroethylene (PTFE), polyamide (PI), epoxy, polyurethane, silicon, and glass. In one embodiment, wherein the detection electrode is made of a material selected from the group consisting of: gold, platinum, carbon-based materials, silver paste, nickel, aluminum, and copper. In one embodiment, the carbon-based material is selected from the group consisting of: carbon nanotubes, graphene, and carbon paste. However, the material for the chip and the electrode according to the present invention is not limited thereto, and materials that can be used for preparing chips or electrodes in the related art can be applied to the present invention.

In one embodiment, the microchip of the present invention is highly integrated, small and portable. In one embodiment, the microchip overall dimensions of (3 ~ 10) cm (0.2 ~ 2.0) cm. In one embodiment, the microchip of the present invention can achieve rapid, accurate, convenient, integrated, automated detection of platelet function in clinical blood or plasma samples. In one embodiment, the microchip is capable of providing results of platelet testing within 15 minutes, preferably within 10 minutes, more preferably within 5 minutes after the addition of the sample.

2. External device adapted to microchip of the present invention

In one aspect, the invention also provides an external device adapted to the microchip of the invention. In one embodiment, the external device comprises: an interface for assembling the microchip, a fluid control device, an external detection circuit, and an output device. In one embodiment, the fluid control device is configured to connect with a sample outlet of the microchip and provide a negative pressure to the microchip when the microchip is mated with the external device through the interface. In one embodiment, the external detection circuit is configured to electrically connect to the detection electrode 42 to detect an electrical signal upon coagulation of the blood sample when the microchip is mated with the external device via the interface. In one embodiment, the output device is configured to display the detection result. In one embodiment, the external device of the present invention further comprises: an element capable of providing a magnetic field outside the detection chamber 41 when the microchip is fitted with the external device through the interface.

3. The invention provides a system for platelet detection

In one aspect, the invention also provides a system for platelet testing. In one embodiment, the system comprises: (a) the microchip of the present invention; and (b) an external device of the present invention. In one embodiment, the system of the microchip is adapted on an external device.

4. The method for detecting the blood platelet of the invention

In one aspect, the invention also provides a method for platelet testing. In one embodiment, the method comprises the steps of: (a) Assembling the microchip of the present invention on the external device of the present invention or providing the system of the present invention; (b) Adding a blood sample to a sample inlet of a sample inlet region of the microchip; and (c) an output device in the external device reads the results of the platelet testing. In one embodiment, the method of the present invention further comprises: before, after or simultaneously with step (b), a magnetic field is provided outside the detection chamber 41.

5. Advantages of the invention

The invention realizes the rapid, accurate, convenient, integrated and automatic detection of the platelet function in clinical blood or plasma samples by the microfluidic chip technology, and lays a foundation for realizing the bedside detection of the platelet function. The microchip of the invention can synchronously and uniformly disperse the sample in a plurality of channels, and the control is arranged on the chip, thereby synchronously analyzing a plurality of platelet function detection indexes. The microchip of the present invention pre-embeds the reaction reagents in solid form in the reagent storage area and dissolves and mixes the reagents by the movement of the sample fluid, significantly reducing system complexity and increasing chip shelf life. The microchip can realize the high-efficiency mixing of a sample and a pre-embedded reagent, and on one hand, the pre-embedded reagent is uniformly dispersed and begins to be mixed due to the design of an inlet and an outlet in a reagent storage area; on the other hand, the mixing area further improves the mixing efficiency through the design of one or more folded S-shaped flow channels and a plurality of baffles which are arranged in the flow channels, form an included angle with the flow direction of the sample and are mutually spaced; and the detection zone can also stir the sample entering the detection chamber more fully through the magnetic beads arranged to rotate under the magnetic field. The microchip of the present invention analyzes the platelet aggregation process in real time by measuring the electrical impedance. Therefore, the microchip of the invention has high integration level, is small and portable, is simple and convenient to operate, has high timeliness of platelet detection, can be used for bedside detection, and can monitor the dynamic change trend of platelet function in the treatment process.

Therefore, the microfluidic chip of the present invention has at least the following technical advantages:

(1) The inspection process is rapid: only about 10 minutes are required from the insertion of the test card to the final data acquisition;

(2) The operation process is simple and convenient: the micro-fluidic chip can be automatically controlled and does not depend on inspectors;

(3) The test result is accurate: the detection process can simulate various physiological coagulation processes;

(4) And (3) application expandability: a plurality of detection indexes can be designed on the chip for synchronous detection according to clinical requirements;

(5) Less blood is needed: only less than 1ml of peripheral blood is needed to complete the rapid test under various conditions each time; and

(6) Small size and convenient carrying.

Detailed Description

The present invention will be further described with reference to specific examples, which should not be construed as limiting the scope of the invention. Those skilled in the art can make various changes or modifications to these specific embodiments without departing from the scope of the present invention, and the embodiments after such changes or modifications still fall within the scope of the present invention.

The present embodiment provides a microchip for platelet measurement based on a microfluidic flow channel, as shown in fig. 1 to 3, comprising:

the sample inlet region 1 has a main body including a sample inlet 11 and a branch flow channel 12. One end of the sample inlet is open, the tested biological sample is added into the sample inlet through a pipette gun and the like, and the other end of the sample inlet is connected with the branch flow passage so as to enter the downstream flow passage. The flow resistance of each branch flow channel is equal by adjusting the length and the width of the flow channel, and the time required for the sample to enter the reagent storage area through the branch flow channel is equal.

The reagent storage zone 2 comprises a circular chamber 21 for storing the solid reagent, and a duct 22 and a duct 23 located diagonally to communicate the inlet zone with the mixing zone, respectively. The solid reagents are pre-embedded in a circular chamber so that the solid reagents dissolve and begin to mix after the sample is introduced. For a round chamber, the design of arranging the inlet and the outlet on the diagonal line can promote the sample to be fully contacted and mixed with the pre-embedded solid reagent, so that the solid reagent is dispersed more uniformly.

The mixing region 3 comprises a plurality of sections of curved flow channels, and baffles 31 arranged in an array manner are arranged in the flow channels. The included angle between the baffle and the moving direction of the liquid in the flow channel is 15-90 degrees, so that the sample and the reagent mixed liquid which originally move in a laminar flow form turbulent flow at the baffle, and the mixing is accelerated. The baffles are arranged in an array manner in the flow channel and repeatedly appear at a certain interval, and the interval range of the baffles is 0.1-1 mm. The sample and reagent mixed solution passes through the 5-20 sections of the bent flow channels in the mixing zone, so that the mixing time of the sample and the reagent is greatly prolonged, the reagent is uniformly dispersed in the sample and fully reacts, and the platelets are fully activated.

The detection region 4 includes detection chambers 41 arranged in parallel, and a pair of detection electrodes 42 disposed in each detection chamber. The detection chamber may be circular or square, and the sample and reagent mixture completely fills the detection chamber and slightly overflows downstream. The planar electrodes are connected to a peripheral detection circuit via electrode pads 43 for functional analysis of platelets in the sample by electrical impedance testing. The sample outlet 44 communicates with a fluid control device, such as a micro-pump, which provides suction to drive liquid from the sample inlet to the detection zone.

The foregoing is merely a preferred embodiment of the invention and is not intended to limit the invention in any manner. While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that this is by way of example only, and that the scope of the invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to the technical contents disclosed above without departing from the technical scope of the present invention, and the changes and modifications all fall into the protective scope of the present invention.

Claims (12)

1. A microchip for platelet testing, wherein said microchip comprises the following areas in communication with each other:

a sample inlet region 1, said sample inlet region 1 comprising a sample inlet 11 for adding a blood sample and one or more sample flow channels 12 connecting the sample inlet 11 with one or more storage chambers 21, respectively;

a reagent storage area 2, said reagent storage area 2 comprising one or more storage chambers 21 that can be used for storing solid reagents;

a mixing zone 3, said mixing zone 3 comprising one or more mixing flow channels for connecting said one or more storage chambers 21 with one or more detection chambers 41, respectively, and mixing said blood sample with said solid reagent therein;

a detection zone 4, said detection zone 4 comprising one or more detection chambers 41 for detecting platelets of said blood sample and a pair of detection electrodes 42 arranged in each detection chamber 41; and

-a sample outlet adapted to be connected to a fluid control means providing a negative pressure.

2. The microchip of claim 1, wherein the sample outlet is disposed in the detection zone 4; or wherein the microchip further comprises a waste zone 5, the sample outlet being provided in the waste zone 5.

3. The microchip according to claim 1 or 2, wherein the number of sample flow channels 12 is 2-8, preferably 3-6, more preferably 4-5, preferably wherein the width and length of each of the sample flow channels 12 is adapted to equalize the flow resistance of each flow channel.

4. The microchip of any one of claims 1-3, wherein one or more of the storage chambers 21 comprises a pre-embedded reagent, and wherein the blood sample is contacted and/or mixed with the reagent in the storage chamber 21, preferably wherein at least one of the storage chambers 21 does not comprise a pre-embedded reagent, as a blank control.

5. The microchip as claimed in claims 1 to 4, wherein

The storage chamber 21 is a cylinder or a cube chamber, preferably the height of the storage chamber is 0.1-5 mm, preferably the diameter of the bottom area of the cylinder chamber is 1-10 mm or the length and/or width of the bottom area of the cube chamber is 1-10 mm; and/or

The detection chamber 41 is a cylinder or a cube chamber, preferably the height of the detection chamber is 0.1-5 mm, preferably the diameter of the bottom area of the cylinder chamber is 0.5-10 mm or the length and/or width of the bottom area of the cube chamber is 1-10 mm.

6. The microchip according to any one of claims 1 to 5, wherein the mixing channel is a circular channel or an S-shaped channel having one or more turns, preferably the mixing channel has a height and/or width of 0.5 to 5 mm, preferably the number of turns is 1 to 50, preferably 5 to 20, more preferably 10 to 15, preferably each of the turns has a length of 0.5 to 20 mm, preferably 1 to 10 mm, preferably the mixing channel has a plurality of baffles arranged therein at an angle to the flow direction of the blood sample, spaced from each other, preferably the angle is 15 to 165 degrees, preferably the spaced distance is 0.1 to 1 mm.

7. The microchip according to any one of claims 1 to 6, wherein a protrusion is provided on the inner surface of the mixing channel, preferably the height and/or width of the protrusion is 10% to 90%, more preferably 20% to 80%, more preferably 30% to 70% of the height and/or width of the mixing channel.

8. The microchip of any one of claims 1-7, wherein magnetic beads are disposed within the detection chamber 41, the magnetic beads being capable of agitating a sample entering the detection chamber 41 via a magnetic field.

9. The microchip according to any one of claims 1 to 8, wherein the detection electrode 42 is connected to an external detection circuit for detecting an electrical signal of coagulation of the blood sample, preferably the electrical signal is an electrical impedance signal.

10. An external device adapted to the microchip of any of claims 1-9, the external device comprising:

an interface for mounting said microchip;

a fluid control device that connects to the sample outlet of the microchip and provides a negative pressure to the microchip when the microchip is mated with the external device through the interface;

an external detection circuit electrically connected to the detection electrode 42 to detect an electric signal when the blood sample is coagulated when the microchip is fitted to the external device through the interface;

the output device is used for displaying the detection result; and

optionally an element capable of providing a magnetic field outside the detection chamber 41 when the microchip is adapted to the external device through the interface.

11. A system for platelet testing, comprising:

(a) A microchip according to any one of claims 1-9; and

(b) The external device according to claim 10, wherein the external device,

wherein the microchip is adapted on the external device.

12. A method for platelet testing, comprising:

(a) Mounting a microchip according to any one of claims 1-9 on an external device according to claim 10, or providing a system according to claim 11;

(b) Adding a blood sample to the sample inlet 11 of the sample inlet zone 1 of the microchip;

(c) An output device in the external device reads the results of the platelet testing; and

optionally before, after or simultaneously with step (b), providing a magnetic field outside the detection chamber 41.

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