Microfluidic chip for filtering blood impurities

Abstract

The application provides a blood impurity filtering micro-fluidic chip, which comprises a filtering part, an inlet, an outlet, a flushing port and a waste liquid outlet, the filtering part has a filtering structure, the inlet, the outlet, the flushing port and the waste liquid outlet are communicated with the filtering part; the inlet is used for introducing raw blood, and the raw blood introduced by the inlet can flow through the filtering part and then flow out through the outlet; the flushing port is used for introducing a flushing liquid, and the flushing liquid introduced by the flushing port can flow through the filtering part and then flow out through the waste liquid outlet, thereby solving the technical problem that the micro-fluidic chip is prone to blockage when processing blood.

Description

Technical Field

[0001] This invention relates to the field of blood microfluidics, and more particularly to a blood impurity filtration microfluidic chip. Background Technology

[0002] Some microfluidic chips are used to process blood, requiring blood to be fed into them. However, blood may contain impurities such as lipid clots and blood clots; these impurities can clog the microfluidic channels, slowing down blood flow or even blocking the channels completely. Summary of the Invention

[0003] The purpose of this invention is to provide a microfluidic chip for filtering blood impurities, so as to solve the technical problem that microfluidic chips are prone to clogging when processing blood.

[0004] The above-mentioned objectives of the present invention can be achieved by the following technical solutions:

[0005] This invention provides a microfluidic chip for filtering blood impurities, comprising: a filter section, an inlet, an outlet, a rinsing port, and a waste liquid outlet. The filter section has a filter structure, and the inlet, outlet, rinsing port, and waste liquid outlet are all connected to the filter section.

[0006] The inlet is used to introduce raw blood, and the raw blood introduced through the inlet can flow through the filter section and then out through the outlet.

[0007] The flushing port is used to introduce flushing liquid, and the flushing liquid introduced through the flushing port can flow through the filter section and then flow out through the waste liquid outlet.

[0008] In a preferred embodiment, the liquid inlet is directly connected to the filter section, and / or the liquid outlet is directly connected to the filter section, and / or the rinsing port is directly connected to the filter section, and / or the waste liquid outlet is directly connected to the filter section.

[0009] In a preferred embodiment, the filtration unit has an inlet end and an outlet end, and raw blood flows from the inlet end to the outlet end for filtration; the liquid inlet and the waste liquid outlet are connected to the inlet end, and the liquid outlet and the rinsing port are connected to the outlet end.

[0010] In a preferred embodiment, the inlet, outlet, flushing port, and waste outlet are connected to a pressurized fluid-passing device. The pressurized fluid-passing device can control the inlet to introduce raw blood at a first pressure, while simultaneously applying a second pressure to the flushing port and waste outlet, and a third pressure to the outlet. The first pressure is greater than the second pressure, and the second pressure is greater than the third pressure. The pressurized fluid-passing device can also control the flushing port to introduce flushing liquid at a fourth pressure, while simultaneously applying a fifth pressure to the inlet and outlet, and a sixth pressure to the waste outlet. The fourth pressure is greater than the fifth pressure, and the fifth pressure is greater than the sixth pressure.

[0011] In a preferred embodiment, the filtration section includes a filtration channel, and the filtration structure includes a plurality of impurity interceptors spaced apart in the filtration channel.

[0012] In a preferred embodiment, the filtration unit includes a plurality of filtration structures, which are spaced apart along the direction from the inlet end to the outlet end, and the density of the impurity interceptors in the filtration structures near the outlet end is greater than the density of the impurity interceptors in the filtration structures near the inlet end.

[0013] In a preferred embodiment, at least in the region of the filter channel near the inlet end, the width of the filter structure is smaller than the width of the filter channel; and / or, at least in the region of the filter channel near the inlet end, a plurality of filter structures are spaced apart along the width direction of the filter channel, and an overflow channel is provided between adjacent filter structures.

[0014] In a preferred embodiment, the impurity interceptor has a forked portion at one end near the inlet end, and the forked portion forms a groove with an opening facing the inlet end.

[0015] In a preferred embodiment, a groove is formed between two adjacent impurity interceptors along the width direction of the filter channel.

[0016] In a preferred embodiment, the width of the groove at the end near the inlet is greater than the width at the end near the outlet.

[0017] The features and advantages of this invention are:

[0018] When this blood impurity filtering microfluidic chip is in operation, raw blood is first introduced through the inlet. The blood flows through the filtration section, where impurities are filtered out. The filtered blood then flows out through the outlet and proceeds to the downstream application device, preventing clogging. After a period of time, a flushing process is performed. Flushing liquid is introduced through the flushing port and flows through the filtration structure, washing away impurities retained in the structure. The flushing liquid containing impurities flows out through the waste liquid outlet. By filtering the raw blood before introducing it into the downstream application device, this blood impurity filtering microfluidic chip prevents clogging. Furthermore, the chip is easy to flush, and the flushing process does not interfere with the inlet and outlet, which helps ensure the long-term stable operation of the blood impurity filtering microfluidic chip and the downstream application device. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A schematic diagram showing the connection between an embodiment of the blood impurity filtering microfluidic chip provided by the present invention and a downstream application device;

[0021] Figure 2 A schematic diagram showing the connection between another embodiment of the blood impurity filtering microfluidic chip provided by the present invention and a downstream application device;

[0022] Figure 3 for Figure 2 A magnified view of point A in the image;

[0023] Figure 4 for Figure 3 A magnified view of point B in the image;

[0024] Figure 5 A schematic diagram of another embodiment of the blood impurity filtering microfluidic chip provided by the present invention;

[0025] Figure 6 This is a partial schematic diagram of another embodiment of the filtration structure in the blood impurity filtration microfluidic chip provided by the present invention.

[0026] Explanation of icon numbers:

[0027] 10. Filter section; 11. Filter channel; 12. Inlet end; 13. Outlet end;

[0028] 20. Filter structure; 21. Flow channel;

[0029] 30. Impurity interceptor; 31. Forked portion; 32. Groove;

[0030] 41. Liquid inlet; 42. Liquid outlet; 43. Rinse outlet; 44. Waste liquid outlet;

[0031] 50. Downstream application devices. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Option 1

[0034] This invention provides a microfluidic chip for filtering blood impurities, such as... Figures 1-5 As shown, the blood impurity filtration microfluidic chip includes: a filter section 10, an inlet 41, an outlet 42, a rinsing port 43, and a waste liquid outlet 44. The filter section 10 has a filter structure 20. The inlet 41, outlet 42, rinsing port 43, and waste liquid outlet 44 are all connected to the filter section 10. The inlet 41 is used to introduce raw blood, and the raw blood introduced through the inlet 41 can flow through the filter section 10 and then out through the outlet 42. The rinsing port 43 is used to introduce rinsing liquid, and the rinsing liquid introduced through the rinsing port 43 can flow through the filter section 10 and then out through the waste liquid outlet 44.

[0035] When this blood impurity filtering microfluidic chip is in operation, raw blood is first introduced through the inlet 41. The blood flows through the filter section 10, where impurities are filtered by the filter structure 20. The filtered blood then flows out through the outlet 42 and proceeds to the downstream application device 50, preventing clogging of the downstream application device 50. After a period of time, rinsing is performed by introducing rinsing liquid through the rinsing port 43. The rinsing liquid flows through the filter structure 20, flushing out impurities retained in the filter structure 20. The rinsing liquid containing impurities flows out through the waste liquid outlet 44. By using this blood impurity filtering microfluidic chip to filter the raw blood before introducing it into the downstream application device 50, clogging by impurities can be avoided. Furthermore, this blood impurity filtering microfluidic chip is easy to rinse, and the rinsing process does not interfere with the inlet 41 and outlet 42, which helps ensure the long-term stable operation of the blood impurity filtering microfluidic chip and the downstream application device.

[0036] In one implementation, such as Figure 1 , Figure 2 and Figure 5As shown, the inlet 41 is directly connected to the filter section 10, and / or the outlet 42 is directly connected to the filter section 10, and / or the rinsing port 43 is directly connected to the filter section 10, and / or the waste liquid outlet 44 is directly connected to the filter section 10. The raw blood introduced through the inlet 41 flows directly into the filter section 10, and the blood filtered by the filter section 10 flows directly to the outlet 42, which helps ensure smooth blood flow. The rinsing liquid introduced through the rinsing port 43 flows directly into the filter section 10, and the rinsing liquid containing impurities flows directly to the waste liquid outlet 44, which helps ensure smooth rinsing liquid flow and improves rinsing efficiency.

[0037] In one embodiment, the filter section 10 has an inlet end 12 and an outlet end 13, through which raw blood flows from the inlet end 12 to the outlet end 13 for filtration; an inlet 41 and a waste liquid outlet 44 are connected to the inlet end 12, and an outlet 42 and a rinsing port 43 are connected to the outlet end 13.

[0038] During blood filtration, blood flows from the inlet end 12 to the outlet end 13; during rinsing, the rinsing liquid flows from the outlet end 13 to the inlet end 12. The flow direction of the rinsing liquid is opposite to that of blood filtration, which makes it easier for the rinsing liquid to carry away the impurities retained in the filter structure 20 during blood filtration, thus improving the rinsing efficiency.

[0039] Furthermore, the inlet 41, outlet 42, flushing port 43, and waste outlet 44 are connected to a pressurized fluid supply device (not shown in the figure). The pressurized fluid supply device can control the inlet 41 to supply raw blood at a first pressure, while simultaneously applying a second pressure to the flushing port 43 and waste outlet 44, and applying a third pressure to the outlet 42. The first pressure is greater than the second pressure, and the second pressure is greater than the third pressure. The pressurized fluid supply device can also control the flushing port 43 to supply flushing liquid at a fourth pressure, while simultaneously applying a fifth pressure to the inlet 41 and outlet 42, and applying a sixth pressure to the waste outlet 44. The fourth pressure is greater than the fifth pressure, and the fifth pressure is greater than the sixth pressure.

[0040] During blood filtration, raw blood is introduced into the inlet 41. At the same time, the pressurized liquid flow device controls the pressure of the inlet 41, outlet 42, flushing port 43, and waste liquid outlet 44 respectively. Since the first pressure is greater than the second pressure, and the second pressure is greater than the third pressure, the blood cannot flow out from the flushing port 43 and the waste liquid outlet 44, but can only flow out from the outlet 42. This eliminates the need for a valve structure and ensures control over the blood flow path.

[0041] During rinsing, rinsing liquid is introduced into rinsing port 43. At the same time, the pressurized liquid supply device controls the pressure of inlet 41, outlet 42, rinsing port 43 and waste liquid outlet 44 respectively. Since the fourth pressure is greater than the fifth pressure, and the fifth pressure is greater than the sixth pressure, the rinsing liquid cannot flow out from inlet 41 and outlet 42, but can only flow out from waste liquid outlet 44. This achieves the goal of eliminating the need for valve structure and ensuring control over the flow path of rinsing liquid.

[0042] Specifically, during blood filtration, the flushing port 43 and waste liquid outlet 44 operate at a second pressure, which can be a range of pressure values. The pressure at the flushing port 43 can be equal to or unequal to the pressure at the waste liquid outlet 44. The outlet 42 operates at a third pressure, which can be zero or less than the second pressure. When the third pressure is zero, the outlet 42 is not pressurized. During flushing, the inlet port 41 and outlet 42 operate at a fifth pressure, which can be a range of pressure values. The pressure at the inlet port 41 can be equal to or unequal to the pressure at the outlet 42. The waste liquid outlet 44 operates at a sixth pressure, which can be zero or less than the fifth pressure. When the sixth pressure is zero, the waste liquid outlet 44 is not pressurized. The pressurized fluid flow device is used to control the pressure at the inlet port 41, outlet 42, flushing port 43, and waste liquid outlet 44. Existing devices in the field of microfluidics can be used, and their specific structures are not described here.

[0043] In one implementation, such as Figures 2-4 As shown, the filter section 10 includes a filter channel 11, and the filter structure 20 includes a plurality of impurity interceptors 30 spaced apart in the filter channel 11. When blood flows through the filter channel 11, impurities in the blood are intercepted by the impurity interceptors 30, thereby achieving impurity filtration.

[0044] Furthermore, the filtration section 10 includes a plurality of filtration structures 20, which are spaced apart along the direction from the inlet end 12 to the outlet end 13. The density of impurity interceptors 30 in the filtration structures 20 near the outlet end 13 is greater than the density of impurity interceptors 30 in the filtration structures 20 near the inlet end 12. Blood flows from the inlet end 12 to the outlet end 13, passing through the plurality of filtration structures 20 for multi-stage filtration; and, as... Figure 1 and Figure 2 As shown, in the front filter structure 20, the spacing between the impurity interceptors 30 is relatively large, which is used to intercept large-sized impurities, while small-sized impurities can pass through the front filter structure 20; in the rear filter structure 20, the spacing between the impurity interceptors 30 is relatively small, and small-sized impurities will be intercepted in the rear dense filter structure 20.

[0045] Furthermore, the arrangement of the impurity interceptors 30 in the filter structure 20 gradually changes from sparse to dense, such as... Figure 1 and Figure 2As shown, the filter structure 20 is divided into at least three units along the direction from the inlet end 12 to the outlet end 13. The density of the impurity interceptors 30 in the filter structure 20 closest to the inlet end 12 is greater than the density of the impurity interceptors 30 in the filter structure 20 of the middle unit, and the density of the impurity interceptors 30 in the filter structure 20 of the middle unit is greater than the density of the impurity interceptors 30 in the filter structure 20 closest to the outlet end 13. The spacing of the impurity interceptors 30 in the last unit of the filter structure 20 must be sufficiently close to ensure that all impurities are intercepted and that blood cells smaller than the impurities can pass through.

[0046] In one embodiment, such as Figure 2 and Figure 3 As shown, at least in the region near the inlet end 12 of the filter channel 11, the width of the filter structure 20 is smaller than the width of the filter channel 11. The region near the inlet end 12 of the filter channel 11 comes into contact with the blood first, and the filter structure 20 in this region needs to intercept more impurities, making it prone to clogging after intercepting a large number of impurities. By ensuring that the filter structure 20 does not fill the entire filter channel 11 in the width direction in the region near the inlet end 12 of the filter channel 11, a flow channel 21 without the filter structure 20 is reserved, so that even if the filter structure 20 is blocked due to intercepting a large number of impurities, the blood can still flow through the flow channel 21.

[0047] In one embodiment, such as Figure 2 and Figure 3 As shown, at least in the region near the inlet end 12 of the filter channel 11, multiple filter structures 20 are spaced apart along the width direction of the filter channel 11, and a flow channel 21 is provided between adjacent filter structures 20. The region near the inlet end 12 of the filter channel 11 is the first to come into contact with blood, and the filter structures 20 in this region are prone to clogging due to the interception of more impurities. By reserving a flow channel 21 in the region near the inlet end 12 of the filter channel 11, blood can still flow through the flow channel 21 even after the filter structures 20 are clogged due to the interception of more impurities.

[0048] The region near the inlet end 12 of the filter channel 11 includes the area where the first n columns of filter structures 20 are located, where n can be any value from 1 to 15. Preferably, in the region near the inlet end 12 of the filter channel 11, the width of some columns of filter structures 20 is smaller than the width of the filter channel 11; some columns are: multiple filter structures 20 are distributed at intervals along the width direction of the filter channel 11, and a flow channel 21 is provided between adjacent filter structures 20.

[0049] Preferably, such as Figure 3As shown, a filter structure 20 includes 3 to 5 rows of impurity interceptors 30 to ensure the interception of impurities and avoid excessive overall resistance that would reduce the flow rate. If there are too many rows of impurity interceptors 30 in a filter structure 20, impurities will generally accumulate in the first few rows of impurity interceptors 30, and no impurities will pass through the later rows of impurity interceptors 30, which means that the interception and filtration effect will not be achieved, and the overall resistance will be increased instead.

[0050] In some implementations, such as Figures 2-4 As shown, the impurity interceptor 30 has a forked portion 31 at the end near the inlet end 12, forming a groove 32 with its opening facing the inlet end 12. Experiments have shown that impurities in blood are mostly linear or block-shaped structures. For linear impurities, the forked portion 31 can trap them; for block-shaped impurities, they will get stuck in the groove 32 formed by the forked portion 31. Furthermore, the width of the impurity interceptor 30 at the end near the outlet end 13 is narrower, allowing the flushing liquid to flow in the direction from the outlet end 13 to the inlet end 12 during flushing, making it easier for impurities to detach from the impurity interceptor 30. Preferably, as... Figure 4 As shown, the impurity interceptor 30 is roughly V-shaped.

[0051] In another embodiment, such as Figure 6 As shown, a groove 32 is formed between two adjacent impurity interceptors 30 along the width direction of the filter channel 11. If two adjacent impurity interceptors 30 are spaced apart, the groove 32 formed between them is through-hole in the direction from the inlet end 12 to the outlet end 13.

[0052] Furthermore, such as Figure 4 and Figure 6 As shown, the width of the groove 32 near the inlet end 12 is greater than the width near the outlet end 13, in order to intercept impurities during filtration and to remove impurities during rinsing. Figure 4 As shown, the end of the groove 32 near the outlet end 13 can be closed. In this case, the width of the end of the groove 32 near the outlet end 13 is equal to 0.

[0053] like Figures 2-4 As shown, the width of the impurity interceptor 30 near the inlet end 12 is greater than the width of the end near the outlet end 13, so that when the raw blood flows from the inlet end 12 to the outlet end 13, the impurity interceptor 30 can intercept impurities in the raw blood; and it is also convenient for impurities to be removed from the impurity interceptor 30 with the flushing liquid during rinsing.

[0054] like Figure 1 and Figure 2As shown, the outlet 42 can be connected to a downstream application device 50. The downstream application device 50 can be a component of the blood impurity filtering microfluidic chip, or it can be a separate module that works in conjunction with the blood impurity filtering microfluidic chip. The downstream application device 50 can be a DLD (Deterministic Lateral Displacement) structure, etc.

[0055] Option 2

[0056] This invention provides a blood impurity filtration method using the aforementioned blood impurity filtration microfluidic chip. The blood impurity filtration method includes a filtration step and a rinsing step. The filtration step includes: introducing raw blood into the inlet 41, the introduced raw blood flowing through the filter section 10 and then flowing out through the outlet 42. The rinsing step includes: introducing rinsing liquid into the rinsing port 43, the introduced rinsing liquid flowing through the filter section 10 and then flowing out through the waste liquid outlet 44. This blood impurity filtration method has all or at least some of the features and effects of the aforementioned blood impurity filtration microfluidic chip, which will not be elaborated further here.

[0057] Furthermore, the filtration step includes: applying a higher pressure to the inlet 41 and introducing blood, applying a lower pressure to the flushing port 43 and the waste liquid outlet 44 at the same time, and not applying pressure to the outlet 42, so that the blood cannot flow out from the flushing port 43 and the waste liquid outlet 44, but can only flow out from the unpressurized outlet 42. The blood passes through the filter structure 20 from the inlet end 12 to the outlet end 13, and impurities in the blood are trapped in the filter structure 20.

[0058] After a period of blood flow, the flushing process begins. The flushing process includes: applying higher pressure to flushing port 43 to introduce flushing fluid; applying lower pressure to inlet port 41 and outlet port 42; and leaving waste outlet 44 unpressurized, preventing flushing fluid from flowing out of inlet port 41 and outlet port 42, allowing it to flow only from waste outlet 44. The flushing fluid flows from outlet end 13 to inlet end 12 through filter structure 20, backflushing out impurities trapped in filter structure 20. The flushing fluid can be physiological saline or other fluids that do not affect the blood, or a solution capable of dissolving blood lipids and blood clots.

[0059] The above descriptions are merely a few embodiments of the present invention. Those skilled in the art can make various modifications or variations to the embodiments of the present invention based on the content disclosed in the application documents without departing from the spirit and scope of the present invention.

Claims

1. A microfluidic chip for filtering blood impurities, characterized in that, include: The system includes a filter section, a liquid inlet, a liquid outlet, a rinsing port, and a waste liquid outlet. The filter section has a filtration structure, and the liquid inlet, the liquid outlet, the rinsing port, and the waste liquid outlet are all connected to the filter section. The inlet is used to introduce raw blood, and the raw blood introduced through the inlet can flow through the filter section and then out through the outlet. The flushing port is used to introduce flushing liquid, and the flushing liquid introduced through the flushing port can flow through the filter section and then flow out through the waste liquid outlet; The liquid inlet, the liquid outlet, the flushing port, and the waste liquid outlet are connected to the pressurized liquid flow device; In filtration mode, the pressurized liquid flow device controls the inlet to introduce raw blood at a first pressure, while simultaneously applying a second pressure to the flushing port and the waste liquid outlet, and a third pressure to the outlet. The first pressure is greater than the second pressure, and the second pressure is greater than the third pressure, so that blood flows out from the outlet. In the flushing mode, the pressurized liquid-passing device controls the flushing port to pass flushing liquid at a fourth pressure, while applying a fifth pressure to the inlet and outlet, and a sixth pressure to the waste liquid outlet. The fourth pressure is greater than the fifth pressure, and the fifth pressure is greater than the sixth pressure, so that the flushing liquid flows out from the waste liquid outlet.

2. The blood impurity filtering microfluidic chip according to claim 1, characterized in that, The liquid inlet is directly connected to the filter section, and / or the liquid outlet is directly connected to the filter section, and / or the rinsing port is directly connected to the filter section, and / or the waste liquid outlet is directly connected to the filter section.

3. The blood impurity filtering microfluidic chip according to claim 1, characterized in that, The filtration unit has an inlet end and an outlet end, and raw blood flows from the inlet end to the outlet end for filtration; the liquid inlet and the waste liquid outlet are connected to the inlet end, and the liquid outlet and the rinsing port are connected to the outlet end.

4. The blood impurity filtering microfluidic chip according to claim 3, characterized in that, The filtration section includes a filtration channel, and the filtration structure includes a plurality of impurity interceptors spaced apart in the filtration channel.

5. The blood impurity filtering microfluidic chip according to claim 4, characterized in that, The filtration section includes a plurality of filtration structures, which are spaced apart along the direction from the inlet end to the outlet end. The density of the impurity interceptors in the filtration structures near the outlet end is greater than the density of the impurity interceptors in the filtration structures near the inlet end.

6. The blood impurity filtering microfluidic chip according to claim 4, characterized in that, At least in the region near the inlet end of the filter channel, the width of the filter structure is smaller than the width of the filter channel; And / or, at least in the region near the inlet end of the filter channel, a plurality of filter structures are spaced apart along the width direction of the filter channel, and an overflow channel is provided between adjacent filter structures.

7. The blood impurity filtering microfluidic chip according to claim 4, characterized in that, The impurity interceptor has a forked portion at one end near the inlet end, and the forked portion forms a groove with an opening facing the inlet end.

8. The blood impurity filtering microfluidic chip according to claim 4, characterized in that, Along the width direction of the filter channel, a groove is formed between two adjacent impurity interceptors.

9. The blood impurity filtering microfluidic chip according to claim 7 or 8, characterized in that, The width of the groove at the end near the inlet is greater than the width at the end near the outlet.

Images