A sperm screening microfluidic organ chip

Abstract

This invention provides a microfluidic organ-on-a-chip for sperm screening, comprising a chip body with a sample injection area, multiple detection channels, and multiple upstream recovery areas of chemotactic gradients. The number of detection channels and upstream recovery areas of chemotactic gradients are the same. The sample injection area and the multiple upstream recovery areas of chemotactic gradients are connected by multiple independent detection channels. Each detection channel includes at least a buffer zone, a microchamber, and a chemotactic gradient generation zone connected sequentially. The sample injection area and the buffer zone are connected by a distribution channel, and the buffer zone and the microchamber are connected by a narrowing channel. The chemotactic gradient generation zone includes a main chemotactic gradient generation channel and tributary channels. The main chemotactic gradient generation channel connects the microchamber and the upstream recovery areas of the chemotactic gradient. Multiple tributary channels are located on both sides of the main chemotactic gradient generation channel and connected to it. Sperm samples are added to the sample injection area, and a transparent glass slide is placed on the chip body to form a sealed structure.

Description

Technical Field

[0001] This invention belongs to the interdisciplinary field of reproductive medicine and biomedical engineering. Specifically, it is a microfluidic organ-on-a-chip for sperm screening. Background Technology

[0002] Sperm screening is a crucial step in assisted reproductive technology. Its core purpose is to separate sperm with strong motility, normal morphology, and intact DNA from semen, thereby improving the conception rate and reducing the risk of embryonic abnormalities. It is mainly used in scenarios such as in vitro fertilization and artificial insemination, and is also involved in the initial screening of donor sperm.

[0003] In existing technologies, sperm screening methods mainly include: (1) Traditional sperm screening methods, such as density gradient centrifugation and the upstream method, rely on centrifugal force or natural swimming ability to separate sperm, but cannot simulate the physiological chemotaxis process; (2) Chemotaxis detection devices: such as Transwell chambers and capillary methods, can only realize static or short-term gradients, and are very different from the in vivo microenvironment; (3) Microfluidic sperm screening chip: Existing chips mostly focus on a single function (such as motility screening or gradient generation) and lack integration of the female reproductive system microenvironment (such as mucus layer and cell interaction); The limitations of existing technologies include: (1) Functional limitation: Traditional methods or chips can only achieve separation or chemotaxis detection, and cannot complete the entire process of "screening-observation-recovery" in a biomimetic microenvironment; (2) Insufficient microenvironment simulation: lack of comprehensive simulation of female reproductive tract mucus resistance, dynamic chemical gradients (such as pH, chemokines) and cell interactions; (3) Poor gradient stability: The gradient of passive diffusion structure has a short maintenance time, and dynamic gradient requires complex fluid control equipment; (4) Throughput and sample size limitations: Traditional methods require a large number of samples and are difficult to test multiple conditions in parallel; (5) Low compatibility of real-time observation: Most devices are not compatible with high-resolution long-term microscopic imaging due to their materials or structures.

[0004] Therefore, it is necessary to provide a microfluidic organ-on-a-chip for sperm screening. Summary of the Invention

[0005] The purpose of this invention is to provide a microfluidic organ-on-a-chip for sperm screening through functional unit design. By constructing a microfluidic chip comprising a sample introduction area, a buffer area, a microchamber, a chemotactic gradient generation area, and an upstream recovery area of ​​the chemotactic gradient, sperm sample introduction and distribution, chemotactic gradient, sperm motility and chemotaxis observation, and sperm separation and recovery can be achieved.

[0006] Therefore, the present invention provides the following technical solution: A microfluidic organ-on-a-chip for sperm screening includes a chip body. The chip body has a sample introduction area, multiple detection channels, and multiple upstream recovery areas of chemotactic gradients. The number of detection channels and upstream recovery areas of chemotactic gradients is the same. The sample introduction area and the multiple upstream recovery areas of chemotactic gradients are connected by multiple independent detection channels. Each detection channel includes at least a buffer zone, a microchamber, and a chemotactic gradient generation zone connected sequentially. The sample introduction area is connected to the buffer zone by a distribution channel, and the buffer zone is connected to the microchamber by a narrowing channel. The chemotactic gradient generation zone includes a main chemotactic gradient generation channel and tributary channels. The main chemotactic gradient generation channel connects the microchamber and the upstream recovery areas of the chemotactic gradient. Multiple tributary channels are located on both sides of the main chemotactic gradient generation channel and connected to it. Sperm samples are added to the sample introduction area, and a transparent glass slide is placed over the chip body to form a sealed structure.

[0007] Preferably, the sample injection area is circular, and a first angle is formed between adjacent distribution channels, the first angle ranging from 10° to 180°.

[0008] Preferably, the buffer zone is provided with isotonic buffer, which diffuses from the buffer zone along the dispensing channel to the injection zone and along the narrowing channel to the microchamber, the chemotactic gradient generation zone, and the upstream recovery zone of the chemotactic gradient.

[0009] Preferably, a chemotactic substance is added to the upstream recovery region of the chemotactic gradient, and the chemotactic substance passively diffuses from the upstream recovery region of the chemotactic gradient to the chemotactic gradient generation region and the microchamber to form a chemotactic concentration gradient.

[0010] Preferably, female reproductive system cells are cultured in the upstream recovery zone of the chemotactic gradient, and the sperm sample is added to the sample introduction zone after the female reproductive system cells have been cultured.

[0011] Preferably, there are multiple tributary channels, which are spaced apart on both sides of the main channel for generating the chemotactic gradient. The tributary channels are J-shaped, with the higher end of the tributary channel being the first end and the lower end being the second end. The first end is located near the microchamber, and the second end is located near the upstream recovery region of the chemotactic gradient. The tributary channel includes a straight section and an arc-shaped section, with the central angle of the arc-shaped section being 10°-270°.

[0012] Preferably, the width of one end of the microchamber connected to the main channel for generating the chemotactic gradient gradually decreases, forming a funnel shape.

[0013] Preferably, the microcavity is provided with a hydrogel or a porous membrane to simulate a barrier under high resistance conditions.

[0014] Preferably, the width range of the distribution channel, the narrowing channel, the chemotactic gradient generation main channel, and the tributary channel is 10μm-100mm.

[0015] Preferably, the area of ​​the buffer zone, the microchamber, and the upstream recovery zone of the chemotactic gradient are all 100 μm. 2 -4cm 2 .

[0016] The sperm screening microfluidic organ-on-a-chip of the present invention has at least the following advantages compared with the prior art: For example, the sperm screening microfluidic organ-on-a-chip provided by this invention has a sample introduction area, a buffer zone, a microchamber, a chemotactic gradient generation zone, and an upstream recovery zone of the chemotactic gradient on the chip body, realizing the functions of gradient generation, biomimetic co-culture, motility observation, chemotactic screening, and sorting and collection; it has multiple detection channels and multiple upstream recovery zones of the chemotactic gradient, with multiple channels running in parallel, enabling simultaneous testing of multiple sets of conditions at one time; a glass slide is covered on the upper surface of the chip to form a locally closed structure, so as to facilitate microscopic observation of sperm migration trajectory and chemotactic behavior; after observation, sperm samples can be recovered in different functional zones.

[0017] For example, the sperm screening microfluidic organ chip provided by this invention utilizes bioactive materials, such as hydrogels and porous membranes, to simulate the resistance microenvironment, such as the mucus layer, and the chemical microenvironment, such as pH value, of the female reproductive system; it can also construct an interaction system between sperm and female reproductive system cells by culturing female reproductive system cells, thereby achieving biomimetic organs and microenvironment. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the sperm screening microfluidic organ-on-a-chip provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the connection between the sample injection area and the dispensing channel provided in an embodiment of the present invention; Figure 3 This is a schematic diagram showing the connection between the tributary channel and the main channel for generating the chemotactic gradient provided in an embodiment of the present invention. Detailed Implementation

[0019] This invention provides a microfluidic organ-on-a-chip for sperm screening.

[0020] Specifically, this sperm screening microfluidic organ-on-a-chip includes a chip body with a sample introduction area, multiple detection channels, and multiple upstream recovery areas of chemotactic gradients. The number of detection channels and upstream recovery areas of chemotactic gradients is the same. The sample introduction area and the multiple upstream recovery areas of chemotactic gradients are connected by multiple independent detection channels. Each detection channel includes at least a buffer zone, a microchamber, and a chemotactic gradient generation area connected sequentially. The sample introduction area and the buffer zone are connected by a distribution channel, and the buffer zone and the microchamber are connected by a narrowing channel. The chemotactic gradient generation area includes a main chemotactic gradient generation channel and tributary channels. The main chemotactic gradient generation channel connects the microchamber and the upstream recovery area of ​​the chemotactic gradient. There are multiple tributary channels, which are located on both sides of the main chemotactic gradient generation channel and connected to it. Sperm samples are added to the sample introduction area, and a transparent glass slide is placed on the chip body to form a sealed structure.

[0021] In some embodiments, the sample injection area is circular, and a first angle is formed between adjacent dispensing channels, the first angle ranging from 10° to 180°.

[0022] In some embodiments, the buffer zone is provided with isotonic buffer, which diffuses from the buffer zone along the dispensing channel to the injection zone and along the narrowing channel to the microchamber, the chemotactic gradient generation zone, and the upstream recovery zone of the chemotactic gradient.

[0023] In some embodiments, a chemotactic substance is added to the upstream recovery region of the chemotactic gradient, and the chemotactic substance passively diffuses from the upstream recovery region of the chemotactic gradient to the chemotactic gradient generation region and the microchamber to form a chemotactic concentration gradient.

[0024] In some embodiments, female reproductive system cells are cultured in the upstream recovery zone of the chemotactic gradient, and sperm samples are added to the injection zone after the female reproductive system cells have been cultured.

[0025] In some embodiments, there are multiple tributary channels, which are spaced apart on both sides of the main channel for generating the chemotactic gradient. The tributary channels are J-shaped, with the higher end of the tributary channel being the first end and the lower end being the second end. The first end is located near the microchamber, and the second end is located near the upstream recovery region of the chemotactic gradient. The tributary channel includes a straight section and an arc-shaped section, with the central angle of the arc-shaped section being 10°-270°.

[0026] In some embodiments, the width of one end of the microchamber connecting the chemotactic gradient generation main channel gradually decreases, forming a funnel shape.

[0027] In some embodiments, the microcavity is provided with a hydrogel or porous membrane to simulate a barrier under high resistance conditions.

[0028] In some embodiments, the widths of the distribution channel, narrowing channel, chemotactic gradient generation main channel, and tributary channel are all in the range of 10μm-100mm.

[0029] In some embodiments, the areas of the buffer zone, the microchamber, and the upstream recovery zone of the chemotactic gradient are all 100 μm. 2 -4cm 2 .

[0030] Specifically, the number of detection channels on the chip body ranges from 2 to 20 to support simultaneous testing of different chemokine concentrations or drug conditions, reducing batch errors; multiple detection channels can be set in parallel or distributed in a circle with the sample injection area as the center.

[0031] To make the objectives, features, and beneficial effects of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It is to be understood that the specific embodiments described below are merely for explaining the present invention and are not intended to limit the present invention. Furthermore, the same or similar reference numerals may be used in the drawings to refer to the same or similar elements in different embodiments, and descriptions of the same or similar elements in different embodiments, as well as descriptions of prior art elements, features, effects, etc., may be omitted.

[0032] Reference Figures 1 to 3 This invention provides a microfluidic organ-on-a-chip for sperm screening.

[0033] This sperm screening microfluidic organochip includes a chip body with a sample introduction area A1, two detection channels, and two upstream recovery areas H1 and H2 of the chemotactic gradient. The number of detection channels and upstream recovery areas H1 and H2 is the same. The sample introduction area A1 and the two upstream recovery areas H1 and H2 are connected by two independent detection channels. Each detection channel includes at least sequentially connected buffer zones C1 and C2, microchambers E1 and E2, and a chemotactic gradient generation area. The sample introduction area A1 is connected to the buffer zones C1 and C2 by dispensing channels B1 and B2. The buffer zones C1 and C2 are connected to... Microchambers E1 and E2 are connected by narrowed channels D1 and D2. The chemotactic gradient generation region includes main chemotactic gradient generation channels F1 and F2 and tributary channels G1 and G2. The main chemotactic gradient generation channels F1 and F2 connect microchambers E1 and E2 and upstream recovery regions H1 and H2. There are multiple tributary channels G1 and G2, which are located on both sides of the main chemotactic gradient generation channels H1 and H2 and connect to them. Sperm samples are added to the sample injection area A1, and a transparent glass slide is covered on the chip body to form a closed structure for observing sperm motility and chemotactic ability.

[0034] Specifically, the chip body can be manufactured using common transparent materials such as transparent glass, PC (Polycarbonate), PMMA (Polymethyl methacrylate), PS (Polystyrene), and PDMS (Polydimethylsiloxane). The transparent glass slides are commonly used light-transmitting consumables such as cover slips and slides. The chip body, manufactured using transparent materials, combined with transparent glass slides, allows for the observation of sperm motility and chemotaxis in all areas and channels.

[0035] Specifically, after observing sperm motility and chemotaxis, the transparent slide was removed to collect sperm in each functional unit: sperm with strong activity and chemotaxis were collected in the upstream collection zones H1 and H2 of the chemotaxis gradient; sperm with strong activity and slightly weak chemotaxis were collected in the tributary channels G1 and G2; sperm with relatively weak activity and chemotaxis were collected in the buffer zones C1 and C2, the narrowed channels D1 and D2, and the microchambers E1 and E2; and sperm with poor activity were collected in the sample injection zone A1 and the distribution channels B1 and B2.

[0036] In some embodiments, the sample injection area A1 is circular, and a first included angle α is formed between adjacent dispensing channels B1 and B2, the first included angle α being in the range of 10°-180°.

[0037] Specifically, the upstream regeneration regions H1 and H2 of the chemotactic gradient are circular.

[0038] In some embodiments, isotonic buffer is added to buffer zones C1 and C2. The isotonic buffer diffuses from buffer zones C1 and C2 along dispensing channels B1 and B2 to sample injection zone A1 and along narrowing channels D1 and D2 to microchambers E1 and E2, chemotactic gradient generation zone and upstream recovery zones H1 and H2 of chemotactic gradient.

[0039] Specifically, the isotonic buffer can be Duchenne phosphate buffer, sodium calcium buffer, or other commercially available buffers. After being added, it can spontaneously flow and diffuse to achieve the "wetting" effect on the functional areas and channels of the chip.

[0040] Specifically, in some embodiments, a microfluidic driven pump and capillary are used to construct a circulating flow channel in the sample injection zone A1 and the upstream recovery zones H1 and H2 of the chemotactic gradient, so as to maintain the chemotactic concentration gradient for a long time. The construction of the circulating flow channel can be achieved by setting capillary tubes with matching pore sizes and disposable pipette tips in the sample injection zone A1 and the upstream recovery zones H1 and H2 of the chemotactic gradient to realize circulating flow.

[0041] In some embodiments, chemotactic substances are added to the upstream recovery regions H1 and H2 of the chemotactic gradient. The chemotactic substances passively diffuse from the upstream recovery regions H1 and H2 of the chemotactic gradient to the chemotactic gradient generation region and the microcavities E1 and E2 to form a chemotactic concentration gradient.

[0042] Specifically, chemokines include, but are not limited to, lipid signaling molecules such as progesterone, follicular fluid, and prostaglandins, protein chemokines such as CXCL12, and small molecules and compounds such as adenosine. They can be one chemokine or a mixture of multiple chemokines.

[0043] In some embodiments, female reproductive system cells are cultured in the upstream recovery zones H1 and H2 of the chemotactic gradient. The upstream recovery zones H1 and H2 integrate biomimetic capabilities, and the female reproductive system cells are oocytes, follicular cells, fallopian tube epithelium, or endometrial epithelial cells. After the female reproductive system cells are cultured, a chemotactic concentration gradient is constructed by passive diffusion. Then, a sperm sample is added to the sample introduction zone.

[0044] In some embodiments, there are multiple tributary channels G1 and G2, which are spaced apart on both sides of the main chemotactic gradient generation channels F1 and F2. The tributary channels G1 and G2 are J-shaped, with the higher end of the tributary channel G1 and G2 being the first end and the lower end being the second end. The first end is located near the microchambers E1 and E2, and the second end is located near the upstream recovery regions H1 and H2 of the chemotactic gradient. The tributary channels G1 and G2 include straight sections and arc-shaped sections, with the central angle β corresponding to the arc-shaped section being 10°-270°.

[0045] Specifically, the preferred number of tributary channels G1 and G2 is 3-10. The tributary channels G1 and G2 form local microchemotactic concentration anomalous units. The tributary channels G1 and G2 form reverse concentration gradient regions in the form of passive diffusion and increase the distance of sperm motility.

[0046] In some embodiments, the width of one end of the microchambers E1 and E2 that connect to the main channels F1 and F2 for generating the chemotactic gradient gradually decreases, forming a funnel shape, which is beneficial for the long-term maintenance of the chemotactic concentration gradient.

[0047] In some embodiments, hydrogels or porous membranes are disposed in microcavities E1 and E2 to simulate a barrier under high resistance conditions.

[0048] Specifically, hydrogel is directly added to microcavities E1 and E2 and locally solidified; porous membranes are cut into suitable shapes and then placed into microcavities E1 and E2. Microcavities E1 and E2 are used to simulate physiological narrow structures in the female reproductive system, such as the cervix and fallopian tubes.

[0049] In some embodiments, the widths of the distribution channels B1 and B2, the narrowing channels D1 and D2, the chemotactic gradient generation main channels F1 and F2, and the tributary channels G1 and G2 are all in the range of 10 μm to 100 mm. Preferably, the widths are all in the range of 20 μm to 100 μm.

[0050] In some embodiments, the areas of buffer zones C1 and C2, microchambers E1 and E2, and upstream recovery zones H1 and H2 of the chemotactic gradient are all 100 μm in size. 2 -4cm 2 The preferred area for buffer regions C1 and C2 is 250 μm. 2 -100mm 2 The preferred area range for microcavities E1 and E2 is 250 μm. 2 -400mm 2 The preferred area range for the upstream recovery regions H1 and H2 of the chemotactic gradient is 250 μm. 2 -400mm 2 .

[0051] The following describes the sperm screening microfluidic organochip process using the sperm screening microfluidic chip provided in this embodiment, specifically including the following steps: S1: The sperm sample is injected into the injection area A1. Isotonic buffer is added to the buffer areas C1 and C2. The isotonic buffer diffuses from the buffer areas C1 and C2 along the distribution channels B1 and B2 to the injection area A1, and along the narrowing channels D1 and D2 to the microchambers E1 and E2, the chemotactic gradient generation area, and the upstream recovery areas H1 and H2 of the chemotactic gradient. S2: Add chemotactic substances to the upstream recovery zones H1 and H2 of the chemotactic gradient. The chemotactic substances passively diffuse from the upstream recovery zones H1 and H2 of the chemotactic gradient to the chemotactic gradient generation zone and microchambers E1 and E2 to form a chemotactic concentration gradient. S3: A closed structure is formed by covering the chip body with a transparent glass slide to observe sperm motility and chemotaxis. S4: After observing sperm motility and chemotaxis, remove the transparent glass slide and collect sperm in each functional unit: collect sperm with strong activity and strong chemotaxis in the upstream collection zones H1 and H2 of the chemotaxis gradient; collect sperm with strong activity and slightly weaker chemotaxis in the tributary channels G1 and G2; collect sperm with relatively weak activity and chemotaxis in the buffer zones C1 and C2, the narrowed channels D1 and D2, and the microchambers E1 and E2; and collect sperm with poor activity in the sample injection zone A1 and the distribution channels B1 and B2.

[0052] In some embodiments, female reproductive system cells are cultured in the upstream recovery regions H1 and H2 of the chemotactic gradient. After the female reproductive system cells are cultured, a chemotactic concentration gradient is constructed by passive diffusion, and then the above steps S1, S3 and S4 are performed to complete sperm screening.

[0053] The sperm screening microfluidic organ chip provided in this embodiment of the invention has the following beneficial effects: 1. By adopting a single-layer chip to integrate the entire process of sample processing, gradient generation, biomimetic culture, observation, and sorting, the integration of functions can be improved, the number of operation steps can be reduced, sample transfer loss can be avoided, and experimental efficiency and data consistency can be improved.

[0054] 2. Control the stability of the concentration gradient, adopt passive + active dual-mode regulation as needed, realize long-term dynamic culture through fluid drive, and can continuously stimulate chemotaxis under conditions closer to physiological conditions, which is suitable for long-term studies such as sperm-cell interaction.

[0055] 3. Utilizing bioactive materials such as hydrogels and porous membranes to simulate the physicochemical properties of the mucus layer, or providing biological signals such as chemokines through cell co-culture, can enhance the biomimeticity of the microenvironment and help improve the physiological relevance of screening results.

[0056] 4. Excellent observation compatibility: It adopts a fully transparent material and a flat micro-chamber design, which is compatible with inverted microscopes, microscope imaging or AI-assisted orbit analysis software image processing, to provide accurate quantitative assessment of sperm motility parameters and provide reliable data to support clinical practice.

[0057] 5. Ensure application scalability. Through modular design, it can be adapted to different experimental needs, such as toxicology testing, biomimetic interaction research, personalized medicine and other scenarios, which is conducive to promoting the translation of reproductive medicine from basic to clinical.

[0058] Although specific embodiments have been described above, these embodiments are not intended to limit the scope of the invention, even when only a single embodiment is described with respect to a particular feature. The feature examples provided in this disclosure are intended to be illustrative and not limiting, unless otherwise stated. In practice, one or more technical features of the dependent claims may be combined with the technical features of the independent claims as needed and where technically feasible, and may be derived from the technical features of the respective independent claims in any suitable manner rather than solely by the specific combinations listed in the claims.

[0059] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A sperm screening microfluidic organ-on-a-chip, characterized in that, The device includes a chip body, which has a sample injection area, multiple detection channels, and multiple upstream recovery areas of chemotactic gradients. The number of detection channels and upstream recovery areas of chemotactic gradients is the same. The sample injection area and the multiple upstream recovery areas of chemotactic gradients are connected by multiple independent detection channels. Each detection channel includes at least a buffer zone, a microchamber, and a chemotactic gradient generation zone connected in sequence. The sample injection area and the buffer zone are connected by a distribution channel, and the buffer zone and the microchamber are connected by a narrowing channel. The chemotactic gradient generation zone includes a main chemotactic gradient generation channel and tributary channels. The main chemotactic gradient generation channel connects the microchamber and the upstream recovery areas of chemotactic gradients. There are multiple tributary channels, which are located on both sides of the main chemotactic gradient generation channel and connected to it. A sperm sample is added to the sample injection area, and a transparent glass slide is placed on the chip body to form a sealed structure.

2. The sperm sorting microfluidic organ-on-chip of claim 1, wherein, The sample injection area is circular, and a first angle is formed between adjacent distribution channels, with the first angle ranging from 10° to 180°.

3. The sperm sorting microfluidic organ-on-chip of claim 1, wherein, The buffer zone is supplemented with isotonic buffer, which diffuses from the buffer zone along the dispensing channel to the injection zone and along the narrowing channel to the microchamber, the chemotactic gradient generation zone, and the upstream recovery zone of the chemotactic gradient.

4. The sperm sorting microfluidic organ-on-chip of claim 1, wherein, A chemotactic substance is added to the upstream recovery region of the chemotactic gradient. The chemotactic substance passively diffuses from the upstream recovery region of the chemotactic gradient to the chemotactic gradient generation region and the microchamber to form a chemotactic concentration gradient.

5. The sperm sorting microfluidic organ-on-chip of claim 1, wherein, Female reproductive system cells are cultured in the upstream recovery zone of the chemotactic gradient. After the female reproductive system cells are cultured, sperm samples are added to the sample introduction zone.

6. The sperm sorting microfluidic organ-on-chip of claim 1, wherein, There are multiple tributary channels, which are spaced apart on both sides of the main channel for generating the chemotactic gradient. Each tributary channel is J-shaped, with the higher end being the first end and the lower end being the second end. The first end is located near the microchamber, and the second end is located near the upstream recovery region of the chemotactic gradient. Each tributary channel includes a straight section and an arc-shaped section, with the central angle of the arc-shaped section being 10°-270°.

7. The sperm sorting microfluidic organ-on-chip of claim 1, wherein, The width of the microchamber, which connects to one end of the chemotactic gradient generation main channel, gradually decreases, forming a funnel shape.

8. The sperm sorting microfluidic organ-on-chip of claim 1, wherein, The microcavities are equipped with hydrogels or porous membranes to simulate barriers under high resistance conditions.

9. The sperm screening microfluidic organ-on-a-chip according to claim 1, characterized in that, The width range of the distribution channel, the narrowing channel, the chemotactic gradient generation main channel, and the tributary channel is 10μm-100mm.

10. The sperm screening microfluidic organ-on-a-chip according to claim 1, characterized in that, The area of the buffer zone, the microchamber and the chemotactic gradient upstream recovery zone ranges from 100 pm 2 - 4 cm 2 .

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