Microfluidic chip and method for constructing in vitro biological model

Abstract

The invention discloses a microfluidic chip and an in-vitro biological model construction method, a substrate is provided with a hydrogel channel and a culture fluid channel which are communicated with each other, the extension direction of the hydrogel channel is the longitudinal flow direction of hydrogel, and a cover plate covers the substrate and covers the hydrogel channel and the culture fluid channel. The communication position of the hydrogel channel and the culture fluid channel is divided with the groove structure as the boundary, the groove structure is provided with a plurality of grooves, the grooves extend in the longitudinal flow direction and are distributed at intervals in the longitudinal flow direction, and after hydrogel enters the hydrogel channel, the grooves can prevent the hydrogel from flowing into the culture fluid channel. According to the present invention, the stable gel interface can be formed at the junction position of the hydrogel channel and the culture fluid channel, such that the cells in the culture fluid channel can be easily adhered to the gel interface, and the exchange of the nutrients can be performed through the hydrogel so as to easily ensure the authenticity and the effectiveness of the cell in-vitro culture data research.

Description

(19) State Intellectual Property Office (12) Invention Patent Application (10) Application Publication Number (43) Application Publication Date (21) Application Number 202511345115.9 (22) Application Date 2022.08.12 (66) Domestic Priority Data 202210908280.0 2022.07.29 CN (62) Divisional Application Data 202210967792.4 2022.08.12 (71) Applicant Jiangsu Aiweide Biotechnology Co., Ltd. Address 7th Floor, Building 1, No. 188, Fuchunjiang Road, Suzhou High-tech Zone, Jiangsu Province 215153 (72) Inventor Requests Not to Disclose Name (74) Patent Agency Beijing Hengbo Intellectual Property Agency Co., Ltd. 11528 Patent Attorney Duan Huolin (51) Int.Cl. B01L 3 / 00 (2006.01) C12M 3 / 00(2006.01) C12M 1 / 00(2006.01) (54) Invention Title: Method for Constructing Microfluidic Chip and In Vitro Biological Model (57) Abstract: This application discloses a method for constructing a microfluidic chip and an in vitro biological model. The substrate has a hydrogel channel and a culture fluid channel that are interconnected. The extension direction of the hydrogel channel is the longitudinal flow direction of the hydrogel. A cover plate is placed on the substrate and covers the hydrogel channel and the culture fluid channel. The connection between the hydrogel channel and the culture fluid channel is divided by a groove structure. The groove structure has multiple grooves. The grooves extend along the longitudinal flow direction and are arranged at intervals along the longitudinal flow direction. After the hydrogel enters the hydrogel channel, the grooves can block the hydrogel from flowing into the culture fluid channel. A stable gel interface can be formed at the junction of the hydrogel channel and the culture fluid channel, which helps the cells in the culture fluid channel to adhere to the gel interface. Nutrients can be exchanged through the hydrogel, which helps to ensure the authenticity and effectiveness of cell culture data research. Claims (2 pages), Description (10 pages), Drawings (6 pages), CN 121060636 A 2025.12.05 CN 1 21 06 06 36 A 1. A microfluidic chip, characterized in that it comprises: a substrate having a hydrogel channel and a culture fluid channel interconnected, wherein the extension direction of the hydrogel channel is the longitudinal flow direction of the hydrogel; a cover plate, covering the substrate and covering the hydrogel channel and the culture fluid channel; a groove structure, wherein the connection between the hydrogel channel and the culture fluid channel is divided by the groove structure, the groove structure having one or more grooves, the grooves being recessed at least relative to the channel wall of the hydrogel channel, and the grooves extending along the longitudinal flow direction; wherein, after the hydrogel is injected into the hydrogel channel, the grooves can prevent the hydrogel from flowing into the culture fluid channel.2. The microfluidic chip according to claim 1, wherein the groove is recessed relative to the channel walls of both the hydrogel channel and the culture fluid channel. 3. The microfluidic chip according to claim 2, wherein the groove structure includes a first groove structure disposed on the substrate and a second groove structure disposed on the cover plate, the first groove structure including one or more first grooves, the second groove structure including one or more second grooves, and the groove including the first groove and the second groove. 4. The microfluidic chip according to claim 3, wherein the first groove and the second groove are disposed opposite each other in the stacking direction of the cover plate and the substrate, or the first groove and the second groove are disposed offset in the stacking direction of the cover plate and the substrate. 5. The microfluidic chip according to claim 1, wherein the hydrogel flows from the hydrogel channel to the culture fluid channel in a transverse flow direction, and when each groove structure includes multiple grooves, the multiple grooves are arranged at intervals along the transverse flow direction, and there is a protrusion between adjacent grooves within the same groove structure. 6. The microfluidic chip according to claim 1, wherein the groove is a rectangular groove, one of the groove walls is connected to one of the channel walls of the hydrogel channel, and the connected groove wall is perpendicular to the channel wall. 7. The microfluidic chip according to claim 1, wherein the hydrogel channel includes a mass exchange section and a hydrogel inlet section and a hydrogel outlet section respectively connected to both ends of the mass exchange section, the mass exchange section communicating with the culture fluid channel; the groove structure includes a first groove structure disposed on the substrate and a second groove structure disposed on the cover plate, the first groove structure and the second groove structure being located at the communication point between the mass exchange section and the culture fluid channel, and the first groove structure including a plurality of first grooves, the second groove structure including a plurality of second grooves, and the groove including the first groove and the second groove. 8. The microfluidic chip according to claim 1, wherein the culture fluid channel comprises: a culture fluid channel segment communicating with the hydrogel channel; a culture fluid inlet segment communicating with one end of the culture fluid channel segment and arranged at an angle to the culture fluid channel segment; and a culture fluid outlet segment communicating with the other end of the culture fluid channel segment and arranged at an angle to the culture fluid channel segment. 9. The microfluidic chip according to any one of claims 1-8, wherein the cover plate has a plurality of inlet channels, a plurality of inlet connecting holes, a plurality of outlet channels, and a plurality of outlet connecting holes, wherein the flow cross-section of the inlet connecting holes is smaller than that of the claims.The flow cross-section of the inlet channel is smaller than that of the outlet channel; one end of each hydrogel channel is connected to the inlet channel through the inlet channel, and the other end of each hydrogel channel is connected to the outlet channel through the outlet channel; one end of each culture fluid channel is connected to the inlet channel through the inlet channel, and the other end of each culture fluid channel is connected to the outlet channel through the outlet channel. 10. A method for constructing an in vitro biological model, characterized by comprising the following steps: using a microfluidic chip as described in any one of claims 1-9; introducing and solidifying hydrogel in the hydrogel channel of the microfluidic chip, such that the hydrogel forms a gel interface at the junction of the groove structure and the hydrogel channel, providing base rigidity for the cells to facilitate cell adhesion; introducing cells to be cultured into the culture fluid channel of the microfluidic chip, such that the cells adhere to the gel interface, and then introducing relevant cell culture medium to provide nutrients required for cell growth; the hydrogel comprises a mixed hydrogel of matrix gel, collagen, and fibrin; the cells to be cultured comprise epithelial cells and vascular endothelial cells. Claims 2 / 2 pages 3 CN 121060636 A Microfluidic chip and method for constructing an in vitro biological model

[0001] This application is a divisional application of the patent application filed on August 12, 2022, with application number 2022109677924 and invention title "Microfluidic chip". Technical Field

[0002] This application relates to the field of biomedical technology, and in particular to a microfluidic chip and a method for constructing an in vitro biological model. Background Art

[0003] Organ-on-a-chip technology is a technology for in vitro three-dimensional cell culture on a chip. By constructing microchannels, microreaction chambers and other functional components, the components such as cells, fluids, gases and extracellular microenvironment in the chip are precisely controlled, thereby generating human micro-tissues and micro-organs with biological functions. Organ-on-a-chip technology has the advantages of integration, low consumption, high throughput, high simulation degree and fast analysis, and has broad application prospects in the fields of new drug development, disease models, personalized medicine and aerospace medicine.

[0004] In the human body, nutrients and gases are transported to various parts of the body through blood vessels, and nutrients, gases and metabolites are exchanged through the interface between organs and blood vessels. In order to simulate this structure in the human body, many organ-on-a-chip technology studies have used porous membranes to construct such interfaces. Vascular endothelial cells and cells corresponding to organs are cultured on both sides of the porous membrane to simulate the cell arrangement and interface function of the organ and blood vessel interface. Adding porous membranes places high demands on the properties and biocompatibility of the membranes themselves, and the presence of porous membranes can also affect cell movement in various channels.The free interaction and migration between them, on the other hand, the bonding method of porous membranes in the chip is relatively complex. Summary of the Invention

[0005] The embodiments of this application provide a method for constructing a microfluidic chip and an in vitro biological model, which can enhance the fluid confinement effect in the microfluidic chip to improve the yield of constructing the microfluidic chip.

[0006] In a first aspect, embodiments of this application provide a microfluidic chip, comprising:

[0007] a substrate having a hydrogel channel and a culture fluid channel communicating with each other, wherein the hydrogel channel extends in the longitudinal flow direction of the hydrogel;

[0008] a cover plate covering the substrate and fitting over the hydrogel channel and the culture fluid channel;

[0009] a groove structure, wherein the communication between the hydrogel channel and the culture fluid channel is divided by the groove structure, the groove structure having one or more grooves, the grooves being recessed at least relative to the channel wall of the hydrogel channel, and the grooves extending along the longitudinal flow direction;

[0010] wherein, after the hydrogel is injected into the hydrogel channel, the grooves can prevent the hydrogel from flowing into the culture fluid channel.

[0011] In some embodiments, the grooves are recessed relative to both the channel walls of the hydrogel channel and the culture fluid channel.

[0012] In some embodiments, the groove structure includes a first groove structure disposed on the substrate and a second groove structure disposed on the cover plate. The first groove structure includes one or more first grooves, and the second groove structure includes one or more second grooves. The groove includes the first groove and the second groove.

[0013] In some embodiments, the first groove and the second groove are disposed opposite to each other in the stacking direction of the cover plate and the substrate, or the first groove and the second groove are disposed offset in the stacking direction of the cover plate and the substrate.

[0014] In some embodiments, the hydrogel flows from the hydrogel channel to the culture fluid channel in a crossflow direction. When each groove structure includes multiple grooves, the multiple grooves are arranged at intervals along the crossflow direction, and there is a protrusion between two adjacent grooves in the same groove structure.

[0015] In some embodiments, the groove is a rectangular groove, one of the groove walls is in contact with one of the hydrogel channel walls, and the in contacting groove wall is perpendicular to the channel wall.

[0016] In some embodiments, there is one hydrogel channel and two culture fluid channels, the hydrogel channel is located between the two culture fluid channels, and the groove structure is provided between each culture fluid channel and the hydrogel channel.

[0017] In some embodiments, the hydrogel channel includes a mass exchange section and a hydrogel inlet section and a hydrogel outlet section respectively connected to both ends of the mass exchange section, the mass exchange section being in communication with the culture fluid channel;

[0018] The groove structure includes a first groove structure disposed on the substrate and a second groove structure disposed on the cover plate, the first groove structure and the second groove structure being located at the communication between the mass exchange section and the culture fluid channel, and the first groove structure including a plurality of first grooves, the second groove structure including a plurality of second grooves, the groove including the first groove and the second groove.

[0019] In some embodiments, the culture fluid channel includes:

[0020] a culture fluid channel section, communicating with the hydrogel channel;

[0021] a culture fluid inlet section, communicating with one end of the culture fluid channel section and being arranged at an angle to the culture fluid channel section;

[0022] a culture fluid outlet section, communicating with the other end of the culture fluid channel section and being arranged at an angle to the culture fluid channel section.

[0023] In some embodiments, the substrate has a plurality of inlet channels, a plurality of inlet connecting holes, a plurality of outlet channels, and a plurality of outlet connecting holes. The flow cross-section of the inlet connecting holes is smaller than the flow cross-section of the inlet channels, and the flow cross-section of the outlet connecting holes is smaller than the flow cross-section of the outlet channels;

[0024] One end of each hydrogel channel is connected to an inlet channel through an inlet connecting hole, and the other end of each hydrogel channel is connected to an outlet channel through an outlet connecting hole;

[0025] One end of each culture fluid channel is connected to an inlet channel through an inlet connecting hole, and the other end of each culture fluid channel is connected to an outlet channel through an outlet connecting hole.

[0026] In a second aspect, embodiments of this application provide a method for constructing an in vitro biological model, characterized by comprising the following steps:

[0027] using a microfluidic chip as described above;

[0028] introducing and solidifying hydrogel within the hydrogel channel of the microfluidic chip, such that the hydrogel forms a gel interface at the junction of the groove structure and the hydrogel channel, providing base rigidity for the cells to facilitate cell adhesion;

[0029] introducing cells to be cultured into the culture fluid channel of the microfluidic chip, such that the cells adhere to the gel interface, and then introducing relevant cell culture medium to provide the nutrients required for cell growth;

[0030] the hydrogel comprises a mixed hydrogel of matrix gel, collagen, and fibrin;

[0031] the cells to be cultured comprise epithelial cells and vascular endothelial cells.

[0032] Based on the microfluidic chip and the method for constructing in vitro biological models provided in the embodiments of this application, at least the following beneficial effects are achieved:

[0033] By connecting a hydrogel channel with a culture fluid channel, and dividing the connection point with a groove structure as the boundary, the groove structure can prevent the hydrogel from flowing into the culture fluid channel from the hydrogel channel, so that a stable gel interface can be formed at the junction of the hydrogel channel and the culture fluid channel. Cells in the culture fluid channel can adhere to the gel interface and exchange nutrients through the hydrogel. The groove structure has multiple grooves, which extend along the longitudinal flow direction. Multiple grooves all have a limiting effect on the hydrogel to prevent the hydrogel from flowing into the culture fluid channel, which can improve the stability of the hydrogel in the hydrogel channel, so as to construct a growth environment that is closer to that of organisms, thereby helping to ensure the authenticity and effectiveness of cell in vitro culture data research. Brief Description of the Drawings

[0034] In order to more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 is a schematic diagram of the structure of a microfluidic chip in one embodiment of this application;

[0036] Figure 2 is a schematic diagram of the structure of a substrate in one embodiment of this application;

[0037] Figure 3 is a cross-sectional schematic diagram of a microfluidic chip in one embodiment of this application;

[0038] Figure 4 is another cross-sectional schematic diagram of a microfluidic chip in one embodiment of this application;

[0039] Figure 5 is a cross-sectional schematic diagram of a microfluidic chip (with multiple grooves) in one embodiment of this application;

[0040] Figure 6 is a schematic diagram of the structure of hydrogel acting between a cover plate and a substrate in one embodiment of this application;

[0041] Figure 7 is another schematic diagram of the structure of hydrogel acting between a cover plate and a substrate in one embodiment of this application;

[0042] Figure 8 is yet another schematic diagram of the structure of hydrogel acting between a cover plate and a substrate in one embodiment of this application;

[0043] Figure 9 is a schematic diagram of the structure of a cover plate in one embodiment of this application;

[0044] Figure 10 is a flowchart of the method of using a microfluidic chip for a cell aggregate chip in one embodiment of this application;

[0045] Figure 11 is a flowchart of a method for using a microfluidic chip in a kidney cell chip according to one embodiment of this application.

[0046] Reference numerals:

[0047] 10, substrate; 11, hydrogel channel; 111, material exchange section; 1111, first material exchange section; 1112, second material exchange section; 112, hydrogel inlet section; 113, hydrogel outlet section; 12, culture fluid channel; 121, culture fluid inletSection; 122, Culture fluid outlet section; 123, Culture fluid channel section; 13, Expansion section;

[0048] 20, Cover plate; 21, Liquid inlet channel; 22, Liquid inlet connecting hole; 23, Liquid outlet channel; 24, Liquid outlet connecting hole;

[0049] 31, First groove structure; 311, First groove; 32, Second groove structure; 321, Second groove;

[0050] H, Crossflow direction; Z, Longitudinal flow direction; D, Stacking direction. Detailed Embodiments

[0051] In order to make the purpose, technical solution and advantages of this application clearer, the following describes this application in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0052] In the human body, nutrients and gases are transported to various parts of the body through blood vessels, and nutrients, gases and metabolites are exchanged through the interface between organs and blood vessels. To simulate this structure in the human body, many organ-on-a-chip technologies have used porous membranes to construct such interfaces. Vascular endothelial cells and cells corresponding to organs are cultured on both sides of the porous membrane to simulate the cell arrangement and interface function of the organ and blood vessel interface. Adding a porous membrane places high demands on the properties and biocompatibility of the porous membrane itself. The presence of the porous membrane also affects the free interaction and migration of cells between the channels. On the other hand, the way the porous membrane is integrated into the chip is relatively complex.

[0053] To solve the above problems, please refer to Figures 1 to 3. This application provides a microfluidic chip, which includes a substrate 10, a cover plate 20, and a groove structure.

[0054] The substrate 10 has a hydrogel channel 11 and a culture fluid channel 12. The hydrogel channel 11 and the culture fluid channel 12 can be used to deliver at least one of the extracellular microenvironment components such as cells, fluids, gases, and drugs.

[0055] There is one hydrogel channel 11 and one culture fluid channel 12. The culture fluid channel 12 is located on one side of the hydrogel channel 11 and is connected to the hydrogel channel 11. The hydrogel channel 11 is filled with hydrogel, and the culture fluid channel 12 is filled with culture fluid, such as culture medium.

[0056] It should be noted that the hydrogel and culture fluid can be added by gravity without a pump, or by using an external peristaltic pump, syringe pump, or other device to drive the flow of hydrogel and culture medium, so that the hydrogel and culture medium can provide the fluid shear force environment required for cell growth.

[0057] The cover plate 20 is located on the side of the substrate 10 near the hydrogel channel 11 and the culture fluid channel 12, and covers the hydrogel channel 11 and the culture fluid channel 12, so that the hydrogel channel 11 and the culture fluid channel 12 are closed in the middle and open at both ends.The channel is shaped to allow the hydrogel to flow within the hydrogel channel 11 and the culture medium to flow within the culture fluid channel 12.

[0058] A groove structure is provided at the connection between the hydrogel channel 11 and the culture fluid channel 12. The groove structure is used to divide the hydrogel channel 11 and the culture fluid channel 12. The groove structure has a restrictive effect on the fluid. When the hydrogel is injected into the hydrogel channel 11, the groove can prevent the hydrogel from flowing into the culture fluid channel 12, thereby confining the hydrogel within the hydrogel channel 11. When the hydrogel solidifies within the hydrogel channel 11, a gel interface is formed at the junction of the groove and the hydrogel channel 11, providing a suitable base hardness for the cells, facilitating cell adhesion to the gel interface. The cells grow within the hydrogel, and the nutrients in the culture medium can exchange substances with the hydrogel through the gel interface to meet the growth needs of the cells located within the hydrogel.

[0059] Further, the extension direction of the hydrogel channel 11 is the longitudinal flow direction Z of the hydrogel. The grooves extend along the longitudinal flow direction or multiple grooves are arranged at intervals along the longitudinal flow direction. The extension direction of the multiple grooves is consistent with the extension direction of the hydrogel channel 11, and the grooves have a confining effect on the fluid. The multiple grooves can confine the hydrogel in the longitudinal flow direction, and at the same time improve the stability of the hydrogel in the hydrogel channel 11 to form a more stable gel interface, which is conducive to cell attachment to the gel interface, and also conducive to constructing a growth environment that is closer to the real growth environment in organisms.

[0060] Please refer to Figure 2. When there are two culture fluid channels 12, the two culture fluid channels 12 are located on opposite sides of the hydrogel channel 11. The groove structure is located between the hydrogel channel 11 and the culture fluid channel 12. The hydrogel channel 11 is filled with hydrogel to form a three-layer structure of culture medium, hydrogel and culture medium.

[0061] The groove structure restricts the flow of fluid, thus confining the hydrogel within the hydrogel channel 11 to prevent the hydrogel within the hydrogel channel 11 from flowing into the culture fluid channel 12, thereby confining the hydrogel within the hydrogel channel 11; (Specification 4 / 10 pages 7 CN 121060636 A) It also allows the hydrogel to form a gel interface at the junction of the groove structure and the hydrogel channel 11, facilitating cell adhesion. Cells grow in the culture medium and can adhere to the gel interface. The gel interface provides the necessary substrate rigidity for cell growth, facilitating uniform attachment and distribution of cells on the gel interface; simultaneously, the hydrogel channel 11 is located between two culture fluid channels 12, allowing different cells to be cultured within the two culture fluid channels 12, and the culture media within the two culture fluid channels 12 can exchange substances through the hydrogel located within the hydrogel channel 11 to meet the nutrient requirements for cell growth in the two different culture media.

[0062] Taking a kidney biological model as an example, one of the culture fluid channels 12 is brimming with renal epithelial cells, allowing the renal epithelial cells to...Cells adhere to the gel interface; then, renal epithelial cell culture medium is circulated in the culture fluid channel 12 to provide the nutrients required for renal epithelial cell growth. Another culture fluid channel 12 is circulated with vascular endothelial cells to allow them to adhere to the gel interface; then, vascular endothelial cell culture medium is circulated in the culture fluid channel 12 to provide the nutrients required for vascular endothelial cell growth. The renal epithelial cell culture medium and the vascular endothelial cell culture medium can exchange substances through the hydrogel, allowing the renal epithelial cells to absorb nutrients from the vascular endothelial cell culture medium.

[0063] Furthermore, the gel interface can simulate the real interface in a living organism, making the cell growth environment closer to the growth environment in a living organism, thus ensuring the authenticity and validity of the in vitro cell culture data research.

[0064] In some embodiments, please refer to FIG3, the groove structure has a groove, which may be recessed relative to the channel wall of the hydrogel channel 11, so that the groove is located between the hydrogel channel 11 and the culture fluid channel 12. The groove has a confining effect on the fluid. When the hydrogel is injected into the hydrogel channel 11, the groove can prevent the hydrogel from flowing into the culture fluid channel 12. At the same time, the hydrogel can form a gel interface at the junction of the groove and the hydrogel channel 11, so as to facilitate the uniform attachment and distribution of cells on the gel interface, and can provide the base rigidity and growth microenvironment required for cell growth.

[0065] The number of grooves may be one. The groove has a confining effect on the fluid, thereby confining the hydrogel within the hydrogel channel 11. Please refer to FIG5. When the number of grooves is multiple, the grooves can play a multiple blocking role. Increasing the number of grooves can improve the stability of the hydrogel within the hydrogel channel 11.

[0066] Further, the groove may also be recessed relative to the channel walls of both the hydrogel channel 11 and the culture fluid channel 12, so that the groove is located between the hydrogel channel 11 and the culture fluid channel 12.

[0067] Further, referring to FIG3, the groove structure may include a first groove structure 31 disposed on the substrate 10 and a second groove structure 32 disposed on the cover plate 20; the first groove structure 31 includes a first groove 311, and the second groove structure 32 includes a second groove 321. The groove includes the first groove 311 and the second groove 321. The groove has a limiting effect on the fluid, and thus the groove can block the hydrogel from flowing into the culture fluid channel 12, thereby the groove can play a better limiting role.

[0068] In some embodiments, referring to FIG5, the first groove structure 31 may include a plurality of first grooves 311, and the second groove structure 32 may also include a plurality of second grooves 321. The plurality of first grooves 311 and the plurality of second grooves 321 may be arranged sequentially in a direction perpendicular to the extension direction of the hydrogel channel 11. The plurality of first grooves 311 and the plurality of second grooves 321 can play a multiple blocking role. Appropriately increasing the number of grooves can improve the stability of the hydrogel in the hydrogel channel 11.

[0069] Further, please refer to Figure 3 in conjunction with Figure 1. The first groove 311 and the second groove 321 can be arranged opposite each other in the stacking direction D of the cover plate 20 and the substrate 10. Since the groove has a limiting effect on the fluid, the flow of hydrogel can be restricted at the opposite position on the cover plate 20 and the substrate 10. This allows the hydrogel to form an approximately straight gel interface at the junction of the first groove 311 and the second groove 321 with the hydrogel channel 11, so as to facilitate the uniform adhesion and distribution of cells on the gel wall. The simulation of the real interface in the organism is used to make the cell growth environment closer to the growth environment in the organism, which is conducive to ensuring the authenticity and effectiveness of cell culture data research.

[0070] In some embodiments, referring to FIG4 in conjunction with FIG1, the first groove 311 and the second groove 321 may also be staggered in the stacking direction D of the cover plate 20 and the substrate 10. By utilizing the limiting effect of the grooves on the hydrogel, a gel interface can be formed at the junction of the first groove 311 and the second groove 321 with the hydrogel channel 11, thereby preventing the hydrogel from flowing into the culture fluid channel 12 from the hydrogel channel 11. At the same time, since the cells adhere to the gel interface, the limitation of the grooves can make the hydrogel form a more stable gel interface, thereby providing a more stable base hardness for cell adhesion, which is conducive to cell growth. Moreover, the setting of the gel interface is also conducive to the precise control of the pressure in the hydrogel channel 11 and the culture fluid channel 12, so as to provide a growth environment closer to that in organisms for cell growth, thereby helping to ensure the authenticity and effectiveness of cell in vitro culture data research.

[0071] Referring to Figure 5, further, the flow direction of the hydrogel in the hydrogel channel 11 towards the culture fluid channel 12 is the transverse flow direction H of the hydrogel. When each groove structure includes multiple grooves, the multiple grooves are arranged at intervals along the transverse flow direction H, and there is a protrusion between two adjacent grooves in the same groove structure. The groove has a limiting effect on the fluid, thereby preventing the hydrogel from flowing towards the culture fluid channel 12. Furthermore, it can also ensure the stability of the hydrogel in the hydrogel channel 11.

[0072] Further, the groove is a rectangular groove. One of the groove walls is connected to one of the channel walls of the hydrogel channel 11, and the connected groove wall is perpendicular to the channel wall, so that the connection position between the groove and the hydrogel channel 11 forms a contact angle, thereby forming a gel interface at the junction of the groove and the hydrogel channel 11. The channel wall of the hydrogel channel 11 is perpendicular to the groove wall, thereby increasing the limiting effect of the groove on the hydrogel in the hydrogel channel 11.

[0073] When the hydrogel is injected into the hydrogel channel 11 and spreads, please refer to Figure 6, it satisfies Young's equation: γsg-γsl= γlgcosθ, where γsg is the solid-gas interfacial tension, γsl is the solid-liquid interfacial tension, γlg is the liquid-gas interfacial tension, and θ is the contact angle of the liquid on the solid surface.

[0074] When the hydrogel is in contact with the surface of the cover plate 20, it satisfies: γs1g-γs1l=γlgcosθ1, where γs1g is the solid-gas interfacial tension on the surface of the cover plate 20, γs1l is the solid-liquid interfacial tension on the surface of the cover plate 20, γlg is the liquid-gas interfacial tension, and θ1 is the contact angle of the liquid on the surface of the cover plate 20. When the hydrogel is in contact with the surface of the substrate 10, it satisfies: γs2g-γs2l=γlgcosθ2, where γs2g is the solid-gas interfacial tension on the surface of the substrate 10, γs2l is the solid-liquid interfacial tension on the surface of the substrate 10, γlg is the liquid-gas interfacial tension, and θ2 is the contact angle of the liquid on the surface of the substrate 10.

[0075] From the Laplace pressure difference, we know that: Where R1 is the principal radius of curvature of the liquid-side curved surface in the plane perpendicular to the flat plate, and R2 is the principal radius of curvature of the liquid-side curved surface in the plane parallel to the flat plate. For the microfluidic chip structure, R2 = 0, R1 is related to the channel height (the distance between the relative surfaces of the cover plate 20 and the substrate 10) h. According to its geometric relationship, we know that: h = R1cosθ1 + R1cosθ2, where θ1 is the contact angle between the hydrogel and the surface of the cover plate 20, and θ2 is the contact angle of the hydrogel on the surface of the substrate 10. Substituting this into the pressure difference formula above, we get: When the hydrogel reaches the edge, we introduce the characteristic angle θedge, where: is the geometric boundary angle. θ1 or θ2 in the formula needs to be replaced with θedge. In Figure 6

[0076] In Figure 7, γ lg=72mN / m, h=200μm, θ1=80°, θedge=170°. When grooves are only provided on the substrate, the calculated pressure difference is ΔP=-291Pa. At this time, the relative air pressure inside the hydrogel is P1=291Pa.

[0077] In Figure 8, γ lg=72mN / m, h=200μm, θedge1=170°, θedge2=170°. When grooves are provided on both the substrate and the cover plate, the calculated pressure difference is ΔP=-709Pa. At this time, the relative air pressure inside the hydrogel is P2=709Pa.

[0078] As can be seen from the above calculations, P2 > P1. When grooves are provided on both the substrate 10 and the cover plate 20, the hydrogel can withstand a larger air pressure. Therefore, the limiting effect when grooves are provided on both the substrate 10 and the cover plate 20 is better than the limiting effect when grooves are provided only on the substrate 10.

[0079] Therefore, when a pressure of 500 Pa is applied inside the hydrogel, the hydrogel can withstand a larger pressure when grooves are provided on both the substrate 10 and the cover plate 20. Thus, when 500 Pa is applied inside the hydrogel, the hydrogel can still be confined within the hydrogel channel 11.

[0080] In some embodiments, when one groove is provided between the hydrogel channel 11 and the culture fluid channel 12, and the distance between the relative surfaces of the cover plate 20 and the substrate 10 is greater than or equal to 0 μm and less than or equal to 500 μm, and the width of the groove is greater than or equal to 100 μm and less than or equal to 400 μm, and the depth is greater than or equal to 50 μm and less than or equal to 400 μm, when grooves are provided on both the substrate 10 and the cover plate 20, the grooves have a better blocking effect on the hydrosol located in the hydrogel channel 11.

[0081] When multiple grooves are provided between the hydrogel channel 11 and the culture fluid channel 12, and the distance between the relative surfaces of the cover plate 20 and the substrate 10 is greater than or equal to 0 μm and less than or equal to 500 μm, and the width of the groove is greater than or equal to 100 μm and less than or equal to 400 μm, and the depth is greater than or equal to 50 μm and less than or equal to 400 μm, the number of grooves is not less than two, and the grooves have a relatively stable and effective liquid blocking effect on the hydrosol located in the hydrogel channel 11.

[0082] Further, please refer to Figure 2. The hydrogel channel 11 includes a material exchange section 111 and a hydrogel inlet section 112 and a hydrogel outlet section 113 connected to both ends of the material exchange section 111, respectively. The material exchange section 111 is connected to the culture fluid channel 12.

[0083] The material exchange section 111 can be configured as a straight channel. The hydrogel inlet section 112 and the hydrogel outlet section 113 can also be configured as straight channels and connected to the material exchange section 111, so as to form a hydrogel channel 11 from the hydrogel inlet section 112 to the material exchange section 111 and then to the hydrogel outlet section 113, so as to facilitate the addition of hydrogel from the hydrogel inlet section 112 to the material exchange section 111, so as to allow cells located on one or both sides of the material exchange section 111 to adhere.

[0084] Simultaneously, the central axes of the hydrogel inlet section 112, the hydrogel outlet section 113, and the mass exchange section 111 can be aligned on the same straight line to position the hydrogel inlet section 112 and the hydrogel outlet section 113 in a suitable location, facilitating hydrogel addition and collection of excess hydrogel. In some embodiments, the hydrogel inlet section 112 and the hydrogel outlet section 113 may also be angled with the mass exchange section 111, depending on the actual shape and size of the substrate 10 and the cover plate 20; this application does not impose any limitations. It should be noted that setting the hydrogel inlet section 112, the hydrogel outlet section 113, and the mass exchange section 111 as straight channels can reduce the flow resistance of the hydrogel within the hydrogel channel 11, facilitating hydrogel flow.

[0085] In some embodiments, the hydrogel inlet section 112, the hydrogel outlet section 113, and the mass exchange section 111 may also have other shapes, depending on actual needs; this application does not impose any limitations.

[0086] In some embodiments, referring to Figures 1 to 3, the groove structure includes two mutually spaced first groove structures 31 disposed on the substrate 10 and two mutually spaced second groove structures 32 disposed on the cover plate 20. The two first groove structures 31 and the two second groove structures 32 define a material exchange section 111, and the first groove structure 31 includes one or more first grooves 311, and the second groove structure 32 includes one or more second grooves 321. The groove includes the first groove 311 and the second groove 321.

[0087] Referring to Figure 2, the material exchange section 111 includes a first material exchange section (not shown in the figure) and a second material exchange section (not shown in the figure). The first material exchange section is close to the substrate 10, and the second material exchange section is close to the cover plate 20. Two spaced-apart first grooves 311 on the substrate 10 (page 7 / 10, CN 121060636 A) define a first mass exchange section, which restricts the hydrogel and confines it within this section. Similarly, two spaced-apart second grooves 321 on the cover plate 20 define a second mass exchange section, also restricting the hydrogel and confining it within this section. The combined effect of these two first grooves 311 and second grooves 321 confines the hydrogel within the hydrogel channel 11, preventing it from entering the culture fluid channel 12. Furthermore, the combined restriction of the first grooves 311 and second grooves 321 creates a relatively stable gel interface at the junction of the grooves and the hydrogel channel 11, facilitating mass exchange between cells in the culture fluid channel 12 and nutrients within the hydrogel. This stable gel interface also promotes cell adhesion, closely mimicking the growth environment of living organisms, thus ensuring the authenticity and validity of in vitro cell culture data.

[0088] In some embodiments, the first groove structure 31 may include a plurality of first grooves 311, and the second groove structure 32 may include a plurality of second grooves 321. The first grooves 311 and the second grooves 321 cooperate to form a groove and are arranged in the transverse flow direction H of the hydrogel. The multiple grooves can play a role in multiple barriers. Increasing the number of grooves appropriately can prevent the hydrogel from entering the culture fluid channel 12 from the hydrogel channel 11, thereby improving the stability of the hydrogel in the hydrogel channel 11.

[0089] Referring to FIG2, the culture fluid channel 12 may also include a culture fluid channel segment 123 and a culture fluid inlet segment 121 and a culture fluid outlet segment 122 located at both ends of the culture fluid channel segment 123, so as to form a culture fluid channel 12 from the culture fluid inlet segment 121 to the culture fluid channel segment 123 to the culture fluid outlet segment 122, so as to facilitate the addition of culture medium from the culture fluid inlet segment 121 into the culture fluid channel 12 to provide nutrients for cell growth.

[0090] The culture fluid channel 12 is located on one side of the hydrogel channel 11. The culture fluid inlet section 121 and the culture fluid outlet section 122 can be set as straight channels, and an included angle is provided between them and the culture fluid channel section 123 to set the liquid inlet and outlet of the culture medium at appropriate positions on the substrate 10 and the cover plate 20, so as to facilitate the operator to add the culture medium.

[0091] Referring to FIG. 2, the positions of the culture fluid channel 12 and the hydrogel channel 11 can be set in a shape like the Chinese character "chuan". The culture fluid channel 12 composed of the culture fluid inlet section 12, the culture fluid channel section 123 and the culture fluid outlet section 122 is set in a concave shape to set the liquid inlet of the culture fluid inlet section 121 and the liquid outlet of the culture fluid outlet section 122 at appropriate positions, so as to facilitate adding the culture medium and collecting the excess culture medium.

[0092] Further, referring to FIG. 9 and FIG. 1, the substrate 10 has a plurality of liquid inlet channels 21, a plurality of liquid inlet connection holes holes 22, a plurality of liquid outlet channels 23 and a plurality of liquid outlet connection holes 24. The flow cross-section of the liquid inlet connection hole 22 is smaller than that of the liquid inlet channel 21, and the flow cross-section of the liquid outlet connection hole 24 is smaller than that of the liquid outlet channel 23.

[0093] One end of each hydrogel channel 11 is connected to a liquid inlet channel 21 through a liquid inlet connection hole 22, and the other end of each hydrogel channel 11 is connected to a liquid outlet channel 23 through a liquid outlet connection hole 24;

[0094] The hydrogel channel 11 includes a hydrogel inlet section 112, a hydrogel outlet section 113 and a mass exchange section 111. The liquid inlet channel 21 corresponds to the liquid inlet of the hydrogel inlet section 112, and a liquid inlet connection hole 2 is provided on the side of the liquid inlet channel 21 close to the hydrogel inlet section 112. The flow cross-section of the liquid inlet connection hole 22 is smaller than that of the liquid inlet channel 21, so as to add the hydrogel in the liquid inlet channel 21 to the mass exchange section 111 through the liquid inlet connection hole 22. At the same time, the larger cross-section liquid inlet channel 21 facilitates the liquid outlet end of the pipette to enter, and further helps the hydrogel in the pipette to enter the hydrogel inlet section 112 through the liquid inlet connection hole 22. Further, placing the liquid outlet end of the pipette in the liquid inlet channel 21 can also prevent the hydrogel in the pipette from being contaminated. At the same time, a bulging part 13 is provided at the position of the hydrogel inlet section 112 close to the liquid inlet connection hole 22, so that the hydrogel in the liquid inlet connection hole 22 can all enter the hydrogel inlet section 112.

[0095] The liquid outlet channel 23 corresponds to the hydrogel outlet section 113, and a liquid outlet connection hole 24 is provided on the side of the liquid outlet channel 23 close to the hydrogel outlet section 113. The flow cross-section of the liquid outlet connection hole 24 is smaller than that of the liquid outlet channel 23. The smaller cross-section liquid outlet connection hole 24 facilitates connecting the liquid outlet channel 23 and the hydrogel outlet section, and then the hydrogel in the hydrogel outlet section 113 can beExcess hydrogel is discharged into the outlet channel 23; at the same time, the outlet channel 23 with a larger cross-section can store more hydrogel, and the operator can remove it when the amount of hydrogel in the outlet channel 23 reaches a certain amount, so as to improve the removal efficiency of excess hydrogel.

[0096] At the same time, the hydrogel outlet section 113 is provided with an enlarged part 13 near the outlet communication hole 24, so as to gather excess hydrogel into the enlarged part 13, and then the excess hydrogel enters the outlet channel 23 through the outlet communication hole 24 through the enlarged part 13.

[0097] One end of each culture fluid channel 12 is connected to an inlet channel 21 through an inlet communication hole 22, and the other end of each culture fluid channel 12 is connected to the outlet channel 23 through an outlet communication hole 24.

[0098] The culture fluid channel 12 includes a culture fluid channel section 123 and a culture fluid inlet section 121 and a culture fluid outlet section 122 located at both ends of the culture fluid channel section 123; the liquid inlet channel 21 corresponds to the liquid inlet of the culture fluid inlet section 121, and a liquid inlet connecting hole 22 is provided on the side of the liquid inlet channel 21 near the culture fluid inlet section 121. The flow cross section of the liquid inlet connecting hole 22 is smaller than the flow cross section of the liquid inlet channel 21, so that the culture medium in the liquid inlet channel 21 can be added to the culture fluid channel 12 through the liquid inlet connecting hole 22. At the same time, the larger cross section of the liquid inlet channel 21 facilitates the entry of the liquid outlet end of the pipette, thereby helping the culture medium in the pipette to enter the culture fluid channel 12 through the liquid inlet connecting hole 22. Furthermore, placing the liquid outlet end of the pipette in the liquid inlet channel 21 can also prevent the culture medium in the pipette from being contaminated.

[0099] At the same time, an enlarged portion 13 is provided at the position of the culture fluid inlet section 121 near the liquid inlet communication hole 22, so that all the culture medium in the liquid inlet communication hole 22 can enter the culture fluid inlet section 121.

[0100] The liquid outlet channel 23 corresponds to the culture fluid outlet section 122, and a liquid outlet communication hole 24 is provided on the side of the liquid outlet channel 23 near the culture fluid outlet section 122. The flow cross section of the liquid outlet communication hole 24 is smaller than the flow cross section of the liquid outlet channel 23. The smaller cross section of the liquid outlet communication hole 24 facilitates the connection between the liquid outlet channel 23 and the culture fluid outlet section 122, so that the excess culture medium in the culture fluid outlet section 122 can be discharged into the liquid outlet channel 23; at the same time, the larger cross section of the liquid outlet channel 23 can store more excess culture medium, and the operator can remove it when the amount of excess culture medium in the liquid outlet channel 23 reaches a certain amount, so as to improve the removal efficiency of excess culture medium.

[0101] Simultaneously, an enlarged portion 13 is provided at the position of the culture fluid outlet section 122 near the liquid outlet communication hole 24, so as to facilitate the collection of excess culture medium into the enlarged portion 13, and then through the enlarged portion 13, the excess culture medium enters the liquid outlet channel 23 through the liquid outlet communication hole 24.

[0102] Please refer to Figure 10. When the number of culture fluid channels 12 is one, the microfluidic chip of this embodiment is used for...The method of using the cell aggregate chip includes:

[0103] S11, assembling the cover plate 20 and the substrate 10 to form a microfluidic chip.

[0104] S12, sterilizing the microfluidic chip.

[0105] S13, adding hydrogel containing mixed cell aggregates into the hydrogel channel 11. The groove can restrict the hydrogel containing mixed cell aggregates within the hydrogel channel 11. Excess hydrogel flows out through the outlet communication hole 24 from the outlet flow channel 23.

[0106] S14, after the hydrogel containing mixed cell aggregates solidifies, it forms hydrogel strips containing mixed cell aggregates.

[0107] S15, adding cell aggregate culture medium from the inlet flow channel 21, which enters the culture fluid channel 12 through the inlet communication hole 22. Excess culture medium flows out through the outlet communication hole 24 from the outlet flow channel 23.

[0108] S16, performing subsequent detection after the cell aggregate culture is completed.

[0109] Please refer to Figure 11. When the number of culture fluid channels 12 is two, the microfluidic chip of this embodiment is used in the method of using the kidney cell chip on pages 9 / 10 of the specification, CN 121060636 A, as follows:

[0110] S21, Assemble the cover plate 20 and the substrate 10 to form a microfluidic chip.

[0111] S22, Sterilize the microfluidic chip.

[0112] S23, Add Matrigel / collagen / fibrin mixed hydrogel into the hydrogel channel 11. The groove can restrict the Matrigel / collagen / fibrin mixed hydrogel within the hydrogel channel 11. Excess Matrigel / collagen / fibrin mixed hydrogel flows out from the outlet channel 23 through the outlet communication hole 24.

[0113] S24, After the Matrigel / collagen / fibrin mixed hydrogel is cured, Matrigel / collagen / fibrin mixed hydrogel strips are formed.

[0114] S25. Kidney epithelial cells are added into the culture fluid channel 12 through the inlet channel 21, allowing the kidney epithelial cells to adhere to the gel interface. Kidney epithelial cell culture medium is added through the inlet channel 21 and enters the culture fluid channel 12 through the inlet communication hole 22. Excess culture medium flows out through the outlet communication hole 24 and out through the outlet channel 23.

[0115] S26. Vascular endothelial cells are added into the culture fluid channel 12 through the inlet channel 21, allowing the vascular endothelial cells to adhere to the gel interface. Vascular endothelial cell culture medium is added through the inlet channel 21 and enters the culture fluid channel 12 through the inlet communication hole 22. Excess culture medium flows out through the outlet communication hole 24 and out through the outlet channel 23.

[0116] S27. After successful cell culture, the kidney-endothelial organ model is completed for subsequent testing.

[0117] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components; in the description of this application...It should be understood that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing this application 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, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0118] The above are only preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application. Instruction Manual 10 / 10 Page 13 CN 121060636 A Figure 1 Figure 2 Instruction Manual Appendix 1 / 6 Page 14 CN 121060636 A Figure 3 Figure 4 Figure 5 Instruction Manual Appendix 2 / 6 Page 15 CN 121060636 A Figure 6 Figure 7 Figure 8 Instruction Manual Appendix 3 / 6 Page 16 CN 121060636 A Figure 9 Instruction Manual Appendix 4 / 6 Page 17 CN 121060636 A Figure 10 Instruction Manual Appendix 5 / 6 Page 18 CN 121060636 A Figure 11 Instruction Manual Appendix 6 / 6 Page 19 CN 121060636 A Abstract Abdominal ultrasound examination method, system and device The present application discloses a microfluidic chip and a method for constructing an in vitro biological model. A substrate is provided with a hydrogel channel and a culture fluid channel that are interconnected. The extension direction of the hydrogel channel itself is the longitudinal flow direction of a hydrogel. A cover plate is disposed on the substrate and covers the hydrogel channeland the culture fluid channel. A groove structure serves as a boundary that delimits a junction between the hydrogel channel and the culture fluid channel, wherein the groove structure comprises a plurality of grooves. The grooves extend along the longitudinal flow direction and are spaced apart along the longitudinal flow direction. After the hydrogel is introduced into the hydrogel channel, the grooves can block the hydrogel from flowing into the culture fluid channel, thereby forming a stable hydrogel interface at an interface region between the hydrogel channel and the culture fluid channel. This facilitates adherence of cells within the culture fluid channel to the hydrogel interface, and enables nutrient exchange through the hydrogel, thereby ensuring the authenticity and validity of data obtained from in vitro cell culture studies.

Claims

1. A microfluidic chip, characterized by, The microfluidic chip comprises: a substrate having one hydrogel channel and one culture fluid channel, the hydrogel channel having a longitudinal direction of the hydrogel; a cover plate covering the substrate and covering the hydrogel channel and the culture fluid channel; a groove structure separating the hydrogel channel and the culture fluid channel, the groove structure having one or more grooves, the groove being recessed relative to the channel wall of the hydrogel channel and extending along the longitudinal direction of the hydrogel; wherein, after the hydrogel is injected into the hydrogel channel, the groove can block the hydrogel from flowing into the culture fluid channel.

2. The microfluidic chip of claim 1, wherein, The groove is recessed relative to the channel wall of the hydrogel channel and the culture fluid channel.

3. The microfluidic chip of claim 2, wherein, The groove structure comprises a first groove structure provided on the substrate and a second groove structure provided on the cover plate, the first groove structure comprising one or more first grooves, the second groove structure comprising one or more second grooves, the groove comprising the first groove and the second groove.

4. The microfluidic chip of claim 3, wherein, The first groove and the second groove are arranged in alignment or misalignment in the stacking direction of the cover plate and the substrate.

5. The microfluidic chip of claim 1, wherein, When the groove structure comprises a plurality of grooves, the plurality of grooves are arranged in intervals along the cross-flow direction, and adjacent two grooves in the same groove structure have a protrusion therebetween.

6. The microfluidic chip of claim 1, wherein, The groove is a rectangular groove, one groove wall of the groove is in contact with one channel wall of the hydrogel channel, and the groove wall and the channel wall are arranged perpendicularly.

7. The microfluidic chip according to claim 1, wherein: the hydrogel channel comprises a substance exchange section and a hydrogel inlet section and a hydrogel outlet section connected to both ends of the substance exchange section, respectively, the substance exchange section being in communication with the culture fluid channel; the groove structure comprises a first groove structure provided on the substrate and a second groove structure provided on the cover plate, the first groove structure and the second groove structure being located at the communication between the substance exchange section and the culture fluid channel, and the first groove structure comprising a plurality of first grooves and the second groove structure comprising a plurality of second grooves, the groove comprising the first groove and the second groove.

8. The microfluidic chip of claim 1, wherein, The culture fluid channel comprises: a culture fluid channel section in communication with the hydrogel channel; a culture fluid inlet section in communication with one end of the culture fluid channel section and arranged at an angle with the culture fluid channel section; a culture fluid outlet section in communication with the other end of the culture fluid channel section and arranged at an angle with the culture fluid channel section.

9. The microfluidic chip according to any one of claims 1-8, wherein, The cover plate has a plurality of liquid inlet flow channels, a plurality of liquid inlet communication holes, a plurality of liquid outlet flow channels and a plurality of liquid outlet communication holes, the flow cross section of the liquid inlet communication hole is smaller than the flow cross section of the liquid inlet flow channel, and the flow cross section of the liquid outlet communication hole is smaller than the flow cross section of the liquid outlet flow channel; One end of each of the hydrogel channels is communicated with a liquid inlet flow channel through a liquid inlet communication hole, and the other end of each of the hydrogel channels is communicated with the liquid outlet flow channel through a liquid outlet communication hole; One end of each of the culture fluid channels is communicated with a liquid inlet flow channel through a liquid inlet communication hole, and the other end of each of the culture fluid channels is communicated with the liquid outlet flow channel through a liquid outlet communication hole.

10. A method of constructing an in vitro biological model, characterized by, The method comprises the following steps: The microfluidic chip according to any one of claims 1-9 is used; The step of introducing and solidifying hydrogel in the hydrogel channel of the microfluidic chip, so that the hydrogel forms a gel interface at the junction of the groove structure and the hydrogel channel, and provides a base hardness for the cells to facilitate cell adhesion; The step of introducing the cells to be cultured in the culture fluid channel of the microfluidic chip, so that the cells adhere to the gel interface, and then introducing the related cell culture medium to provide the nutrients required for cell growth; The hydrogel comprises a mixed hydrogel of Matrigel, collagen and fibrin; The cells to be cultured include epithelial cells and vascular endothelial cells.

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