Micro-fluidic chip

Abstract

The utility model provides a microfluidic chip and relates to the technical field of microfluidics. Comprising an inlet, an outlet and a micro-channel, the inlet is arranged at the first end of the micro-channel, and the outlet is arranged at the second end of the micro-channel; a micro-pit structure is arranged at the bottom end of the micro-channel, the micro-pit structure comprises a pit wall and a pit bottom, and the pit bottom is arranged at the lower end of the pit wall; the section of the pit wall is in the shape of a horn with an upward opening, and the section of the pit bottom is in the shape of a hemisphere. The cell huddling device is high in cell huddling efficiency, and the size uniformity of grown cell bodies is good; culture of organ-like cells of different sizes can be completed at a time; and the proportion uniformity of various cells forming the organoid is good.

Description

Technical Field

[0001] This utility model relates to the field of microfluidics technology, specifically to a microfluidic chip. Background Technology

[0002] Organoids are miniature cell clusters that grow in a three-dimensional (3D) environment outside the body. Under the influence of cytokines, small molecule inhibitors / activators, culture media, and other additives, these cell clusters self-organize and differentiate into functional cell populations, possessing tissue structures and genetic characteristics similar to corresponding organs. Organoids can mimic the mechanical structure and function of organs in vivo to the greatest extent possible and can be stably passaged for a long time; therefore, they are also called "miniature organs."

[0003] Traditional organoid construction methods often employ methods such as hanging drop, centrifugation, ultra-low adsorption plates, or stirred reactors. These methods often result in organoids with inconsistent sizes, uneven proportions of various cell types, long construction cycles, and high consumption of cells and culture reagents.

[0004] Microfluidic chip technology, through the cross-integration of chemistry, fluid physics, microelectronics, new materials, biology, and biomedical engineering, can simulate the environment inside living organisms on a chip, constructing more biomimetic microenvironments to establish and culture cell or organ models. Microfluidic chips allow for the construction of organoid models using trace amounts of liquid and extremely small numbers of cells.

[0005] The prior art CN212316139U discloses a biomimetic multi-organ chip, which uses a micro-pit structure at the bottom of the cell culture area to capture 3D cell spheres and micro-tissues. However, when the cell suspension is seeded, the cells settle due to gravity, resulting in a large randomness in the landing point, poor cell aggregation, and insufficient uniformity in the size of the grown cells. Furthermore, when fluid is introduced into the chip to flush away the cells, the grown cells are easily washed away, and the micro-pit structure does not effectively fix the grown cells, making it unstable. Utility Model Content

[0006] The purpose of this invention is to provide a microfluidic chip with high cell aggregation efficiency, good uniformity of cell size after growth, and the ability to construct organoid models using only a small amount of liquid and a very small number of cells, for the culture of cell aggregates or organoids.

[0007] To achieve the above objectives, this utility model employs the following technical solution:

[0008] A microfluidic chip includes an inlet, an outlet, and a microchannel, wherein the inlet is disposed at a first end of the microchannel, and the outlet is disposed at a second end of the microchannel;

[0009] The bottom of the microchannel is provided with a micropit structure, which includes a pit wall and a pit bottom. The pit bottom is located at the lower end of the pit wall. The cross-sectional shape of the pit wall is a funnel shape with the opening facing upwards, and the cross-sectional shape of the pit bottom is a hemispherical shape.

[0010] Furthermore, the number of micropit structures is multiple, and the multiple micropit structures form a micropit structure array.

[0011] Furthermore, the opening areas of the multiple micro-pit structures in the micro-pit structure array are the same, and the depths of the multiple micro-pit structures in the micro-pit structure array are the same.

[0012] Furthermore, the number of the micro-pit structure arrays is multiple.

[0013] Furthermore, the micropit structure sizes are not uniform in different micropit structure arrays.

[0014] Furthermore, the shape of the pit wall is an inverted cone.

[0015] Furthermore, the shape of the pit wall is an inverted pyramid.

[0016] Furthermore, the number of microchannels is one or more, and the multiple microchannels are connected in parallel.

[0017] Furthermore, the diameter of the micro-pit structure is 100μm-1000μm, and the depth of the micro-pit structure is 10μm-200μm.

[0018] Furthermore, the bottom of the pit is located at the center of the micro-pit structure.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] I. This device adopts a microfluidic chip and a micro-pit structure with a funnel-shaped pit wall and a spherical pit bottom. After the cells settle, they fall into the spherical pit bottom along the funnel-shaped pit wall under the influence of gravity. The cells have high aggregation efficiency and good uniformity of cell size after growth. Using a microfluidic chip, a small amount of liquid and a very small amount of cells are sufficient to construct organoid models.

[0021] Second, the microfluidic chip of this device can achieve cell seeding of all micropits in one go by connecting different microchannels in parallel; and the micropit structure arrays in the microchannels are of different sizes, which can achieve the culture of organoid cells of different sizes in one go.

[0022] Third, the micro-pit structures in the same micro-pit structure array of this device have the same opening area and the same pit depth, which ensures that the number of cells gathered in the pit is highly uniform, and achieves the technical effect of good uniformity of the proportion of various cells constituting organoids; moreover, it is simple to operate and easy to use, and can be applied to a variety of cells for rapid, standardized and reproducible organoid model construction. Attached Figure Description

[0023] Figure 1 A schematic diagram of the structure of a microfluidic chip provided in one embodiment of this utility model;

[0024] Figure 2 A schematic diagram of the micro-pit structure of a microfluidic chip provided in one embodiment of this utility model;

[0025] Figure 3 yes Figure 2 The diagram shows a top view of the micro-pit structure of the microfluidic chip.

[0026] Figure 4 yes Figure 2 The diagram shows a side view of the micro-pit structure of the microfluidic chip.

[0027] Figure 5 A schematic diagram of the micro-pit structure of a microfluidic chip provided for another embodiment of the present invention;

[0028] Figure 6 yes Figure 5 The diagram shows a top view of the micro-pit structure of the microfluidic chip.

[0029] Figure 7 yes Figure 5 The diagram shows a side view of the micro-pit structure of the microfluidic chip.

[0030] In the picture:

[0031] 1. Inlet; 2. Outlet; 3. Microchannel; 4. Micropit structure array; 5. Micropit structure; 6. Pit wall; 7. Pit bottom. Detailed Implementation

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

[0033] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0034] like Figure 1-7 As shown:

[0035] This utility model provides a microfluidic chip, including an inlet 1, an outlet 2 and a microchannel 3, wherein the inlet 1 is disposed at the first end of the microchannel 3 and the outlet 2 is disposed at the second end of the microchannel 3;

[0036] The microchannel 3 has a micropit structure at its bottom, which includes a pit wall 6 and a pit bottom 7. The pit bottom 7 is located at the lower end of the pit wall 6. The pit wall 6 has a funnel shape with the opening facing upwards, and the pit bottom 7 has a hemispherical shape.

[0037] According to a specific embodiment of the present invention, the number of micro-pit structures 5 is multiple, and the multiple micro-pit structures 5 form a micro-pit structure array 4.

[0038] According to a specific embodiment of the present invention, the multiple micro-pit structures 5 in the micro-pit structure array 4 have the same opening area and the multiple micro-pit structures 5 in the micro-pit structure array 4 have the same depth.

[0039] According to a specific embodiment of the present invention, the number of the micro-pit structure array 4 is multiple.

[0040] According to a specific embodiment of the present invention, the micro-pit structures 5 in different micro-pit structure arrays 4 have non-uniform sizes.

[0041] According to a specific embodiment of this utility model, the pit wall 6 is shaped like an inverted cone.

[0042] According to a specific embodiment of this utility model, the pit wall 6 is shaped like an inverted pyramid.

[0043] According to a specific embodiment of the present invention, the number of microchannels 3 is one or more, and the connection method between the multiple microchannels 3 is parallel.

[0044] According to a specific embodiment of the present invention, the diameter of the micro-pit structure 5 is 100μm-1000μm, and the depth of the micro-pit structure 5 is 10μm-200μm.

[0045] According to a specific embodiment of the present invention, the pit bottom 7 is located at the center of the micro-pit structure 5.

[0046] To illustrate the technical solution of this utility model, specific embodiments are described below.

[0047] Example 1

[0048] See Figure 1 This is a schematic diagram of a microfluidic chip according to a specific embodiment of the present invention, including an inlet 1, an outlet 2, and a microchannel 3; the inlet 1 is located at the first end of the microchannel 3, and the outlet 2 is located at the second end of the microchannel 3; a micro-pit structure array 4 is provided at the bottom end of the microchannel 3, and the area of ​​the micro-pit structure array 4 covers the entire width of the microchannel 3;

[0049] There are multiple micro-pit structures 5 in the micro-pit structure array 4. The multiple micro-pit structure arrays 4 are arranged sequentially from inlet 1 to outlet 2 along the fluid flow direction. The dimensions of the micro-pit structures 5 in each individual micro-pit structure array 4 are the same, but the dimensions of the micro-pit structures 5 in different micro-pit structure arrays 4 are different. The dimensions of the micro-pit structures 5 in the micro-pit structure array 4 are arranged sequentially from large to small along the fluid flow direction.

[0050] The micro-pit structure 5 includes a pit wall 6 and a pit bottom 7, with the pit bottom 7 located at the lower end of the pit wall 6. The pit wall 6 has a trumpet-shaped cross-section, and the pit bottom 7 has a hemispherical cross-section. The pit bottom 7 is located at the center of the micro-pit structure 5.

[0051] In an embodiment of this utility model, the microfluidic chip includes two microchannels 3, which are connected in parallel. Fluid can enter the first microchannel and the second microchannel respectively through the inlet 1, so as to complete the micro-pit seeding of all cells at one time.

[0052] In an embodiment of this utility model, three micro-pit structure arrays 4 are provided at the bottom of the first microchannel. The pit walls 6 of all the micro-pit structures 5 are in the shape of inverted cones. The micro-pit structures 5 in the three micro-pit structure arrays 4 are divided into three different sizes. The three sizes of the micro-pit structures 5 with inverted cone-shaped walls are: opening diameter of 300 μm and pit depth of 150 μm; opening diameter of 200 μm and pit depth of 100 μm; and opening diameter of 100 μm and pit depth of 50 μm. They are arranged in descending order along the fluid flow direction. Three micro-pit structure arrays are also provided at the bottom of the second microchannel. 4. In this array, the pit walls 6 of all micropit structures 5 are shaped like inverted pyramids. The micropit structures 5 in the three micropit structure arrays 4 are divided into three different sizes. The three sizes of the micropit structures 5 with inverted pyramid shapes are: opening side length of 300μm and pit depth of 150μm; opening side length of 200μm and pit depth of 100μm; and opening side length of 100μm and pit depth of 50μm. They are arranged in descending order of size along the fluid flow direction. By setting micropit structures of different sizes, cell aggregates of different sizes can be generated at one time, and cell aggregates of different sizes can be studied simultaneously.

[0053] In the embodiments of this utility model, the three different micro-pit structure arrays 4 in the first microchannel each cover the same area of ​​the microchannel 3, and the ratio of the area of ​​the microchannel 3 covered by the three different micro-pit structure arrays 4 along the fluid flow direction is 1:1:1; the three different micro-pit structure arrays 4 in the second microchannel each cover the same area of ​​the microchannel 3, and the ratio of the area of ​​the microchannel 3 covered by the three different micro-pit structure arrays 4 along the fluid flow direction is 7:2:1. This achieves the same number of micro-pit structures of different sizes, so that when statistically analyzing cell growth in micro-pit structures of different sizes in the next step, there is the same number of samples for reference, which can better evaluate the role of micro-pit structures of different sizes on cell growth under the same conditions.

[0054] The working principle of this utility model is as follows:

[0055] During cell culture, fluid is first introduced into the microchannel 3 through inlet 1. After the fluid stabilizes, cell suspension is prepared into the fluid in the microchannel 3 for cell seeding. After entering the fluid in the microchannel 3, the cells are deposited at the bottom of the microchannel 3 under the influence of gravity. After falling into the micropit structure 5 at the bottom of the microchannel 3, the cells fall along the funnel-shaped pit wall 6 into the pit bottom 7 located in the center of the micropit structure 5, allowing the cells to settle and aggregate in the central part, facilitating cell clustering and growth. After the cells have completed settling and clustering, fluid is introduced into the microchannel 3 to flush away excess cells, and subsequent cell aggregate or organoid culture and in situ detection are carried out.

[0056] It should be noted that this invention can not only achieve sedimentation and aggregation culture of one type of cell, but also achieve the above-mentioned technical effects when applied to sedimentation and aggregation culture of multiple types of cells, resulting in good uniformity of the proportions of various cells constituting organoids.

[0057] This invention is simple to operate and easy to use. It can be applied to various cells and is used for rapid, standardized and reproducible construction of organoid models.

[0058] The above embodiments are only for illustrating the technical concept and features of this utility model, and are intended to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be construed as limiting the scope of protection of this utility model. All equivalent transformations or modifications made in accordance with the spirit and essence of this utility model should be included within the scope of protection of this utility model.

Claims

1. A microfluidic chip, characterized by: The microfluidic channel comprises an inlet and an outlet, the inlet is arranged at the first end of the microfluidic channel, and the outlet is arranged at the second end of the microfluidic channel. The bottom end of the microfluidic channel is provided with a micro-pit structure, the micro-pit structure comprises a pit wall and a pit bottom, the pit bottom is arranged at the lower end of the pit wall, the cross-sectional shape of the pit wall is an upward-opening horn shape, and the cross-sectional shape of the pit bottom is a hemispherical shape.

2. The microfluidic chip of claim 1, wherein: The number of the micro-pit structures is multiple, and the multiple micro-pit structures form a micro-pit structure array.

3. The microfluidic chip of claim 2, wherein: The opening areas of the multiple micro-pit structures in the micro-pit structure array are the same, and the depths of the multiple micro-pit structures in the micro-pit structure array are the same.

4. The microfluidic chip of claim 2, wherein: The number of the micro-pit structure arrays is multiple.

5. The microfluidic chip of claim 4, wherein: The sizes of the micro-pit structures in different micro-pit structure arrays are not uniform.

6. The microfluidic chip of claim 1, wherein: The shape of the pit wall is an inverted cone.

7. The microfluidic chip of claim 1, wherein: The shape of the pit wall is an inverted pyramid.

8. The microfluidic chip of claim 1, wherein: The number of the microfluidic channels is one or more, and the connection mode between the multiple microfluidic channels is parallel connection.

9. The microfluidic chip of claim 1, wherein: The diameter of the micro-pit structure is 100 μm-1000 μm, and the depth of the micro-pit structure is 10 μm-200 μm.

10. The microfluidic chip of claim 1, wherein: The pit bottom is arranged at the central position of the micro-pit structure.

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