Micro-fluidic chip

Abstract

The utility model discloses a micro-fluidic chip, which belongs to the technical field of medical instruments and comprises an upper cover and a separation container, the upper cover is mounted on the separation container, a sealing layer is arranged at the top of the separation container, the bottom of the upper cover is abutted against the sealing layer, an inner cavity is defined by the upper cover and the sealing layer, a separation chip group is mounted in the inner cavity, and the separation chip group is mounted on the separation container. The top of the separation chip set abuts against the top of the upper cover, the bottom of the separation chip set abuts against the sealing layer, the separation chip set comprises multiple layers of separation chips, and the separation chips are used for separating blood cells in blood from PRP-enriched plasma. The problem that the position of a boundary layer is difficult to judge and control due to the fact that the thickness of the boundary layer of the plasma and red blood cells after blood centrifugal layering is small is solved, and the platelet-rich plasma which is stable in PRP enrichment multiple, large in amount of collected PRP and small in red blood cell residue is finally prepared.

Description

Technical Field

[0001] This utility model relates to a microfluidic chip and belongs to the field of medical device technology. Background Technology

[0002] Platelet-rich plasma (PRP) is a platelet concentrate obtained by centrifuging autologous whole blood, with a platelet concentration at least twice the baseline concentration. Since PRP preparation currently mostly uses autologous whole blood, PRP usually refers to autologous PRP, which mainly contains platelets, fibrin, and leukocytes. Alpha granules in platelets release a large number of growth factors upon platelet activation. The proportions of these growth factors correspond to the physiological state in the body, playing a crucial role in accelerating wound healing, promoting tissue regeneration and repair, and relieving pain. In recent years, it has been widely applied in various medical fields, showing broad application potential and development prospects.

[0003] Methods for preparing PRP mainly include single-stage centrifugation, double-stage centrifugation, and triple-stage centrifugation, with double-stage centrifugation being the most widely used. Existing PRP preparation kits and equipment require multiple transfers of blood cells and extraction of the PRP product during the preparation process, making it cumbersome. Furthermore, these extractions are all performed manually, leading to product contamination and excessively long preparation times. Secondly, because most centrifugation containers are tubular or cup-shaped, the boundary layer between plasma and red blood cells is thin after blood centrifugation, making it difficult to determine and control the boundary layer's position. This results in unstable PRP enrichment folds, low PRP collection volumes, and high levels of residual red blood cells. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a microfluidic chip that solves the problem of difficulty in judging and controlling the position of the boundary layer caused by the thin thickness of the boundary layer between plasma and red blood cells after blood centrifugation and stratification, so as to finally prepare platelet-rich plasma with stable PRP enrichment multiple, large amount of PRP collected and little red blood cell residue.

[0005] The technical solution adopted by this utility model to solve its existing problems is:

[0006] A microfluidic chip includes a top cover and a separation container. The top cover is mounted on the separation container, and a sealing layer is provided on the top of the separation container. The bottom of the top cover abuts against the sealing layer, and the top cover and the sealing layer form an inner cavity. A separation chip assembly is installed in the inner cavity. The top of the separation chip assembly abuts against the top of the top cover and the bottom abuts against the sealing layer. The separation chip assembly includes multiple separation chips. The separation chips are used for separating blood cells from PRP-enriched plasma in blood.

[0007] Preferably, the separation chip includes a blood inlet, a mirror-image blood channel, multiple outlets, and a mirror-image blood cell outlet. One end of the blood channel is connected to the blood inlet, and the other end of the blood channel is connected to the blood cell outlet.

[0008] Preferably, each blood channel is provided with a constriction section, a larynx and a dilation section connected in sequence, one end of the dilation section is connected to the larynx and the other end of the dilation section is connected to the blood cell outlet.

[0009] A microchannel is mirrored near the throat of the expansion section. One end of the microchannel is connected to the expansion section, and the other end of the microchannel is connected to the PRP outlet.

[0010] Preferably, the sealing layer is provided with multiple PRP inlets and mirrored blood cell inlets, with the PRP inlets and PRP outlets aligned, and the blood cell inlets and blood cell outlets aligned.

[0011] Preferably, the separation container includes a PRP collection area and a blood cell collection area, with the PRP inlet connected to the PRP collection area and the blood cell inlet connected to the blood cell collection area.

[0012] The separation container has an extraction port on the side wall of the PRP collection area.

[0013] Preferably, the top of the cover is provided with a cover injection port, which is aligned with the blood inlet.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0015] This invention features a flexible design, convenient operation, and high preparation efficiency. By utilizing the physical properties of different blood cells and the design of blood channels and microchannels, it solves the problem of difficulty in judging and controlling the position of the boundary layer caused by the thin thickness of the boundary layer between plasma and red blood cells after blood centrifugation. It produces platelet-rich plasma with stable PRP enrichment multiple, large PRP collection volume, and low red blood cell residue, ultimately obtaining platelet-rich plasma with high purity. Furthermore, the design of the bottom of the separation container ensures that the amount of platelet-rich plasma residue is extremely small, thus effectively avoiding waste. Attached Figure Description

[0016] Figure 1 This is a structural diagram of a microfluidic chip according to the present invention;

[0017] Figure 2 This is a top view of a microfluidic chip according to the present invention;

[0018] Figure 3 This is a full sectional view at point AA of the top view of a microfluidic chip according to this utility model;

[0019] Figure 4This is a full sectional view at point BB of the top view of a microfluidic chip according to this utility model;

[0020] Figure 5 This is a top view of a discrete chip of a microfluidic chip according to the present invention;

[0021] Figure 6 This is a partial enlarged view of point C in the top view of a microfluidic chip separator according to this utility model;

[0022] Figure 7 This is a structural diagram of a separation container for a microfluidic chip according to the present invention;

[0023] Figure 8 This is a full sectional top view of a microfluidic chip separation container according to the present invention.

[0024] In the picture:

[0025] 1. Top cover; 101. Top cover injection port; 2. Separation container; 201. Extraction port; 202. Sealing layer; 203. PRP inlet; 204. Blood cell inlet; 205. PRP collection area; 206. Separating layer; 207. Blood cell collection area; 208. Bottom of separation container; 3. Separation chip; 301. Blood inlet; 302. Blood channel; 303. Contraction section; 304. Throat; 305. Dilation section; 306. Microchannel; 307. PRP outlet; 308. Blood cell outlet. Detailed Implementation

[0026] This specification and claims do not distinguish components by differences in name, but by differences in function. In the description of this utility model, it should be understood that terms such as "upper," "lower," "front," "rear," "left," "right," and "horizontal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In this utility model, unless otherwise expressly specified and limited, terms such as "installed," "connected," "joined," and "fixed" should be interpreted broadly. Those skilled in the art can understand the specific meaning of these terms in this utility model according to the specific circumstances.

[0027] like Figures 1-8The microfluidic chip shown includes a top cover 1 and a separation container 2. The top cover 1 is mounted on the separation container 2. The top of the separation container 2 is provided with a sealing layer 202. The bottom of the top cover 1 abuts against the sealing layer 202. The top cover 1 and the sealing layer 202 form an inner cavity. A separation chip assembly is installed in the inner cavity. The top of the separation chip assembly abuts against the top of the top cover 1 and the bottom abuts against the sealing layer 202. The separation chip assembly includes multiple separation chips 3. The separation chips 3 are used to separate blood cells from PRP-enriched plasma in the blood. The separation chip assembly is provided with multiple separation chips 3, which increases the blood holding space and improves the separation efficiency.

[0028] The separation chip 3 includes a blood inlet 301, a mirror-image blood channel 302, multiple PRP outlets 307, and a mirror-image blood cell outlet 308. One end of the blood channel 302 is connected to the blood inlet 301, and the other end is connected to the blood cell outlet 308. Each blood channel 302 has a constriction section 303, a throat 304, and an expansion section 305 connected in sequence. The expansion section 305 has the largest cross-sectional area, the throat 304 has the smallest cross-sectional area, and the constriction section 303 has a medium cross-sectional area. One end of the expansion section 305 is connected to the throat 304, and the other end is connected to the blood cell outlet 308. When blood flows through the blood channel 302, the cross-sectional area of ​​the constriction section 303 gradually decreases, and the blood velocity begins to increase. When the blood reaches the throat 304, the flow velocity reaches its maximum value in the throat 304 section with the smallest cross-sectional area, causing the blood to flow quickly into the expansion section 305.

[0029] A microchannel 306 is mirror-imagely provided near the throat 304 in the expansion section 305. One end of the microchannel 306 is connected to the expansion section 305, and the other end of the microchannel 306 is connected to the PRP outlet 307. The blood inlet 301, PRP outlet 307, blood cell outlet 308, and microchannel 306 on the multilayer separation chip 3 are respectively provided one-to-one.

[0030] The sealing layer 202 is provided with multiple PRP inlets 203 and mirror-arranged blood cell inlets 204. The PRP inlets 203 are aligned with the PRP outlets 307, and the blood cell inlets 204 are aligned with the blood cell outlets 308.

[0031] The separation container 2 also includes a PRP collection area 205 and a blood cell collection area 207. A partition layer 206 is provided between the PRP collection area 205 and the blood cell collection area 207 to separate the PRP collection area 205 and the blood cell collection area 207. The PRP inlet 203 is connected to the PRP collection area 205, and the blood cell inlet 204 is connected to the blood cell collection area 207.

[0032] The separation container 2 has an extraction port 201 on its side wall at the PRP collection area 205. The bottom 208 of the separation container is bent, and the part of the bottom 208 of the separation container inside the PRP collection area 205 is inclined toward the extraction port 201, so that the enriched PRP plasma in the PRP collection area 205 is concentrated on one side of the extraction port 201, which facilitates extraction, reduces residue, and avoids waste.

[0033] The top of the upper cover 1 is provided with an upper cover injection port 101, which is aligned with the blood inlet 301 for blood injection.

[0034] The working principle of a microfluidic chip is as follows:

[0035] The velocity distribution of fluid within a channel typically follows a parabolic shape, with the fastest velocity in the central region and the slowest near the wall. This velocity difference creates a shear gradient within the fluid, meaning the shear force gradually changes from the channel center to the wall. Cells in this environment experience shear gradient lift, which causes lateral displacement. Furthermore, due to their larger size and deformability, red blood cells tend to move towards the channel center during flow. This is because their larger mass makes them more susceptible to inertial lift, and their deformability allows them to quickly adjust their posture and follow the flow. In contrast, platelets are smaller and more rigid. In the channel, platelets are not as strongly affected by inertial lift as red blood cells, but rather by shear gradient lift, causing them to tend to distribute closer to the channel wall.

[0036] Whole blood enters the blood inlet 301 through the top cap injection port 101. As the blood flows within the blood channel 302, a thin, cell-free plasma layer forms on the sidewall of the blood channel 302. Due to their small size and rigidity, platelets tend to distribute near the channel wall. When the blood flows through the constriction section 303, the blood flow speeds up. When it flows through the throat 304, the blood flows into the dilation section 305 at the fastest speed. Because the dilation section 305 has microchannels 306 mirrored near the throat 304, it enhances the lateral migration of platelets, bringing them closer to the channel wall and into the dilation section 305. Blood containing red blood cells flows rapidly into the blood cell outlet 308 along with the main flow. From the blood cell outlet 308, it flows through the blood cell inlet 204 and enters the blood cell collection area 207. Meanwhile, the plasma layer and platelets on the side wall are diverted by the microchannel 306, separated from the blood, and flow through the microchannel 306 into the PRP outlet 307. From the PRP outlet 307, it flows through the PRP inlet 203 and enters the PRP collection area 205. The plasma is then extracted through the extraction port 201 located on the side wall of the separation container 2 in the PRP collection area 205, thus obtaining the PRP enriched solution.

[0037] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A microfluidic chip, comprising a top cover (1) and a separation container (2), wherein the top cover (1) is mounted on the separation container (2), characterized in that: The separation container (2) has a sealing layer (202) on top, and the bottom of the cover (1) abuts against the sealing layer (202). The cover (1) and the sealing layer (202) form an inner cavity. A separation chip assembly is installed in the inner cavity. The top of the separation chip assembly abuts against the top of the cover (1) and the bottom abuts against the sealing layer (202). The separation chip assembly includes multiple separation chips (3). The separation chips (3) are used to separate blood cells from PRP-enriched plasma in the blood.

2. The microfluidic chip according to claim 1, characterized in that: The separation chip (3) includes a blood inlet (301), a mirror-image blood channel (302), multiple PRP outlets (307), and a mirror-image blood cell outlet (308). One end of the blood channel (302) is connected to the blood inlet (301), and the other end of the blood channel (302) is connected to the blood cell outlet (308).

3. The microfluidic chip according to claim 2, characterized in that: Each blood channel (302) is provided with a constriction section (303), a throat (304) and an expansion section (305) connected in sequence. One end of the expansion section (305) is connected to the throat (304), and the other end of the expansion section (305) is connected to the blood cell outlet (308). The expansion section (305) is provided with a microchannel (306) near the throat (304). One end of the microchannel (306) is connected to the expansion section (305), and the other end of the microchannel (306) is connected to the PRP outlet (307).

4. The microfluidic chip according to claim 3, characterized in that: The sealing layer (202) is provided with multiple PRP inlets (203) and mirror-set blood cell inlets (204), with the PRP inlets (203) aligned with the PRP outlets (307) and the blood cell inlets (204) aligned with the blood cell outlets (308).

5. The microfluidic chip according to claim 4, characterized in that: The separation container (2) includes a PRP collection area (205) and a blood cell collection area (207), with a PRP inlet (203) connected to the PRP collection area (205) and a blood cell inlet (204) connected to the blood cell collection area (207). The separation container (2) has an extraction port (201) on its side wall located in the PRP collection area (205).

6. The microfluidic chip according to claim 5, characterized in that: The top of the cover (1) is provided with a cover injection port (101), which is aligned with the blood inlet (301).

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