A microfluidic channel and a dynamic embryo culture dish

Abstract

This invention discloses a microfluidic channel and a dynamic embryo culture dish, relating to the field of embryo culture technology. The microfluidic channel includes a first flow channel segment, a connecting flow channel segment, and a second flow channel segment. The first flow channel segment has a first end and a second end positioned opposite each other. The first end is connected to a reservoir, and the second end is connected to the connecting flow channel segment. The second flow channel segment has a third end and a fourth end positioned opposite each other. The third end is connected to the connecting flow channel segment, and the fourth end is connected to a culture tank. The extension directions of both the connecting flow channel segment and the second flow channel segment are parallel to the horizontal plane, and a preset angle is formed between the extension directions of the first flow channel segment and the connecting flow channel segment, with the preset angle being 150-180 degrees. The microfluidic channel provided by this invention enables automatic replenishment of the culture medium in the culture tank, saving time and effort, improving the control accuracy of the culture medium injection flow rate, shortening the medium change cycle, improving medium change efficiency, and avoiding adverse effects on the embryos.

Description

Technical Field

[0001] This invention relates to the field of embryo culture technology, and more specifically, to a microfluidic channel and a dynamic embryo culture dish. Background Technology

[0002] Currently, during embryo culture, the embryos produce a large amount of metabolic waste and continuously consume nutrients in the culture medium. Therefore, it is necessary to change the culture medium in a timely manner to ensure the embryo's development. The current method of changing the medium involves manually using a pipette to first aspirate the waste liquid from the culture dish and then injecting fresh culture medium. However, this method requires precise control of the aspiration or injection rate to avoid excessively rapid flow that could affect embryo development. Manual operation is time-consuming and labor-intensive, has low precision in flow rate control, a long medium-change cycle, and low efficiency.

[0003] In view of this, it is particularly important to design and manufacture a time-saving, labor-saving, and highly efficient microfluidic channel and a dynamic embryo culture dish, especially in embryo culture. Summary of the Invention

[0004] The purpose of this invention is to provide a microfluidic channel that enables automatic replenishment of culture medium in the culture tank, saving time and effort, improving the control accuracy of the culture medium injection flow rate, shortening the medium change cycle, improving the medium change efficiency, and avoiding adverse effects on the embryo.

[0005] Another objective of this invention is to provide an embryo dynamic medium exchange culture dish that can automatically replenish the culture medium in the culture tank, saving time and effort, improving the control accuracy of the culture medium injection flow rate, shortening the medium exchange cycle, improving the medium exchange efficiency, and avoiding adverse effects on the embryo.

[0006] The present invention is achieved by the following technical solution.

[0007] A microfluidic channel is provided for connecting a storage tank and a culture tank, allowing the culture medium in the storage tank to flow into the culture tank. The microfluidic channel includes a first flow channel section, a connecting flow channel section, and a second flow channel section connected in sequence. The first flow channel section has a first end and a second end arranged opposite to each other. The first end is used to connect to the storage tank, and the second end is connected to the connecting flow channel section. The second flow channel section has a third end and a fourth end arranged opposite to each other. The third end is connected to the connecting flow channel section, and the fourth end is used to connect to the culture tank. When the microfluidic channel is in use, the extension directions of both the connecting flow channel section and the second flow channel section are parallel to the horizontal plane. A preset angle is formed between the extension directions of the first flow channel section and the connecting flow channel section, with the preset angle being 150 degrees to 180 degrees.

[0008] Optionally, the first flow channel section is funnel-shaped, and the cross-sectional area of ​​the flow channel at the first end is larger than the cross-sectional area of ​​the flow channel at the second end.

[0009] Optionally, the cross-section of the flow channel at the first end is rectangular, with a width of 4.5mm-6.5mm and a height of 1.2mm-1.8mm. And / or, the flow channel cross-section at the second end is rectangular, with a width of 1.8mm-3.3mm and a height of 1mm-1.3mm.

[0010] Optionally, the second flow channel section is funnel-shaped, and the cross-sectional area of ​​the flow channel at the fourth end is larger than that at the third end.

[0011] Optionally, the cross-section of the flow channel at the fourth end is rectangular, with a width of 4.5mm-6.5mm and a height of 1.2mm-1.8mm. And / or, the flow channel cross-section at the third end is rectangular, with a width of 1.8mm-3.3mm and a height of 1mm-1.3mm.

[0012] Optionally, the connecting flow channel section is circular, the cross-sectional area of ​​the connecting flow channel section is larger than the cross-sectional area of ​​the flow channel at the second end, and the cross-sectional area of ​​the connecting flow channel section is larger than the cross-sectional area of ​​the flow channel at the third end.

[0013] Optionally, the microfluidic channel also includes a switching valve that extends into the connecting channel section and is used to regulate the flow rate of the culture medium.

[0014] Optionally, the switching valve includes a valve body and a baffle connected to each other. The baffle is disposed within the connecting flow channel section, and the valve body is used to drive the baffle to rotate relative to the connecting flow channel section to adjust the size of the gap between the baffle and the side wall of the connecting flow channel section.

[0015] Optionally, the microfluidic channel also includes a drive unit connected to the valve body, which is used to drive the baffle to rotate through the valve body.

[0016] An embryo dynamic medium-changing culture dish includes a reservoir, a culture tank, and the aforementioned microfluidic channel. The microfluidic channel includes a first flow channel segment, a connecting flow channel segment, and a second flow channel segment connected in sequence. The first flow channel segment has a first end and a second end arranged opposite to each other. The first end is connected to the reservoir, and the second end is connected to the connecting flow channel segment. The second flow channel segment has a third end and a fourth end arranged opposite to each other. The third end is connected to the connecting flow channel segment, and the fourth end is connected to the culture tank. When the microfluidic channel is in use, the extension directions of both the connecting flow channel segment and the second flow channel segment are parallel to the horizontal plane. A preset angle is formed between the extension directions of the first flow channel segment and the connecting flow channel segment, with the preset angle being 150 degrees to 180 degrees. When the embryo dynamic medium-changing culture dish is placed on a horizontal plane, the first end is higher than the second end, and the bottom of the reservoir is higher than the bottom of the culture tank.

[0017] The microfluidic channel and the embryo dynamic medium exchange culture dish provided by this invention have the following beneficial effects: The microfluidic channel provided by this invention has a first flow channel segment with a first end and a second end arranged opposite to each other. The first end is used to communicate with a storage tank, and the second end is used to communicate with a connecting flow channel segment. The second flow channel segment has a third end and a fourth end arranged opposite to each other. The third end is used to communicate with the connecting flow channel segment, and the fourth end is used to communicate with a culture tank. When the microfluidic channel is in use, the extension directions of both the connecting flow channel segment and the second flow channel segment are parallel to the horizontal plane. A preset angle is formed between the extension directions of the first flow channel segment and the connecting flow channel segment, with the preset angle being 150-180 degrees. Compared with the prior art, the microfluidic channel provided by this invention, due to the use of a first flow channel segment inclined to the horizontal plane, a first end for communicating with the storage tank, and a fourth end for communicating with the culture tank, can realize automatic replenishment of culture medium in the culture tank, saving time and effort, improving the control accuracy of the culture medium injection flow rate, shortening the medium change cycle, improving the medium change efficiency, and avoiding adverse effects on embryos.

[0018] The embryo dynamic medium exchange culture dish provided by the present invention includes a microfluidic channel, which can realize the automatic replenishment of culture medium in the culture tank, saving time and effort, improving the control accuracy of the culture medium injection flow rate, shortening the medium exchange cycle, improving the medium exchange efficiency, and avoiding adverse effects on the embryo. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A schematic diagram of the structure of the microfluidic channel connecting the liquid storage tank and the culture tank provided in an embodiment of the present invention; Figure 2 A cross-sectional view of the embryo dynamic medium exchange culture dish provided in an embodiment of the present invention; Figure 3 This is a cross-sectional view of the embryo dynamic medium exchange culture dish provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the embryo dynamic medium exchange culture dish provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the switching valve in a microfluidic channel from one perspective, provided in an embodiment of the present invention. Figure 6 This is a schematic diagram of the switching valve in the microfluidic channel provided in an embodiment of the present invention from another perspective; Figure 7 A schematic diagram of the rotating component of the switching valve in the microfluidic channel provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of the structure of the embryo dynamic medium exchange culture dish from one perspective, provided in an embodiment of the present invention. Figure 9 This is a schematic diagram of the structure of the embryo dynamic medium exchange culture dish from another perspective provided in an embodiment of the present invention; Figure 10 This is a schematic diagram of the structure of the lid of the embryo dynamic medium exchange culture dish provided in an embodiment of the present invention.

[0021] Icons: 100 - Embryo dynamic medium exchange culture dish; 110 - Microfluidic channel; 111 - First flow channel section; 1111 - First end; 1112 - Second end; 112 - Connecting flow channel section; 113 - Second flow channel section; 1131 - Third end; 1132 - Fourth end; 114 - Switch valve; 1141 - Valve body; 1142 - Baffle; 1143 - Snap-fit ​​part; 1144 - Rotating component; 120 - Storage tank; 121 - Third step wall; 122 - Fourth step wall; 123 - Limiting column; 130 - Culture tank; 131 - Microchannel; 132 - Washing tank; 133 - First step wall; 134 - Second step wall; 135 - Stop column; 140 - Dish body; 150 - Dish cap; 151 - First through hole; 152 - Clearance hole; 153 - Second through hole. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0025] In the description of this invention, it should be noted that the terms "inner," "outer," "upper," "lower," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use. They are only for the convenience of describing the invention 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 the invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0026] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "connected," "installed," and "connected" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, features in the following embodiments can be combined with each other.

[0028] Please refer to the reference. Figures 1 to 10 This invention provides an embryo dynamic medium-changing culture dish 100 for in vitro embryo culture. It enables automatic replenishment of the culture medium in the culture tank 130, saving time and effort, improving the control precision of the culture medium injection flow rate, shortening the medium-changing cycle, increasing medium-changing efficiency, and avoiding adverse effects on the embryo.

[0029] The embryo dynamic medium exchange culture dish 100 includes a storage tank 120, a culture tank 130, and a microfluidic channel 110. The storage tank 120 is connected to the culture tank 130 through the microfluidic channel 110. The storage tank 120 is used to store culture medium, and the culture tank 130 is used to place embryos and culture them in vitro. Specifically, the bottom wall of the storage tank 120 is higher than the bottom wall of the culture tank 130. One end of the microfluidic channel 110 is connected to and communicates with the bottom wall of the storage tank 120, and the other end is connected to and communicates with the bottom wall of the culture tank 130. The culture medium in the storage tank 120 can flow to the culture tank 130 through the microfluidic channel 110 under the action of gravity until the liquid level of the culture medium in the storage tank 120 is flush with the liquid level of the culture medium in the culture tank 130 (communicating vessel principle), so as to realize the flow function of the culture medium between the storage tank 120 and the culture tank 130 without the need for external driving force, which is simple and efficient. In this way, the culture medium in the storage tank 120 can automatically flow to the culture tank 130 without the need for external driving force, so as to realize the dynamic liquid exchange function of the culture medium in the culture tank 130.

[0030] As one possible implementation, the embryo dynamic medium exchange culture dish 100 includes a dish body 140, a storage pool 120, a culture pool 130, and a microfluidic channel 110, all of which are formed in the dish body 140. That is, the storage pool 120, the culture pool 130, and the microfluidic channel 110 are integrated into one unit to improve the reliability of the connection between the storage pool 120 and the culture pool 130 through the microfluidic channel 110, and to ensure that the culture medium in the storage pool 120 can flow evenly and stably to the culture pool 130, thereby realizing the medium exchange function.

[0031] The microfluidic channel 110 includes a first flow channel section 111, a connecting flow channel section 112, and a second flow channel section 113 connected in sequence. The first flow channel section 111 is inclined to the horizontal plane and has a first end 1111 and a second end 1112 arranged opposite to each other. The first end 1111 is higher than the second end 1112. The first end 1111 is connected to the storage tank 120, and the second end 1112 is connected to the connecting flow channel section 112, so that the culture medium in the storage tank 120 has a tendency to flow from the first end 1111 to the second end 1112. The inclined first flow channel section 111 can increase the flow rate of the culture medium in the first flow channel section 111, thereby improving the medium exchange efficiency. Both the connecting flow channel section 112 and the second flow channel section 113 are located on a horizontal plane. The second flow channel section 113 is provided with a third end 1131 and a fourth end 1132. The third end 1131 is connected to the connecting flow channel section 112, and the fourth end 1132 is connected to the culture tank 130. The culture medium located at the second end 1112 can flow through the connecting flow channel section 112 to the third end 1131, and then through the fourth end 1132 to the culture tank 130. During this process, the horizontally arranged connecting flow channel section 112 and the second flow channel section 113 can slow down the flow rate of the culture medium flowing into the culture tank 130, so as to avoid the culture medium flow rate being too fast and affecting the embryo development in the culture tank 130.

[0032] Specifically, when the microfluidic channel 110 is in use, the extension directions of the connecting channel section 112 and the second channel section 113 are both parallel to the horizontal plane, and a preset angle is formed between the extension directions of the first channel section 111 and the connecting channel section 112. Correspondingly, when the embryo dynamic medium exchange culture dish 100 is placed on a horizontal plane, the first end 1111 is higher than the second end 1112, and the bottom of the reservoir 120 is higher than the bottom of the culture tank 130.

[0033] Furthermore, the preset angle is 150-180 degrees, preferably 165-180 degrees. The size of the preset angle is directly related to the height difference between the storage tank 120 and the culture tank 130. If the preset angle is too small, the oil layer in the storage tank 120 will enter the microfluidic channel 110 and be adsorbed on the inner wall of the microfluidic channel 110, or even flow into the culture tank 130, affecting embryo observation.

[0034] In this way, on the one hand, the culture medium in the culture tank 130 is automatically replenished through the microfluidic channel 110 connecting the storage tank 120 and the culture tank 130, saving time and effort; on the other hand, the flow rate of the culture medium is increased by first using the inclined first flow channel section 111, and then the flow rate of the culture medium is slowed down by using the horizontally set connecting flow channel section 112 and the second flow channel section 113, so as to improve the control accuracy of the culture medium injection flow rate, shorten the medium replacement cycle and improve the medium replacement efficiency while avoiding adverse effects on the embryo.

[0035] Optionally, the first flow channel section 111 is funnel-shaped, with the cross-sectional area of ​​the first end 1111 being larger than that of the second end 1112. This allows the flow velocity of the culture medium to gradually increase as it flows from the first end 1111 to the second end 1112, further improving the medium exchange efficiency. Furthermore, the larger cross-sectional area of ​​the first end 1111 connects to the storage tank 120, enabling the culture medium within the first flow channel section 111 to achieve a more stable equilibrium with the external atmospheric environment through the first end 1111.

[0036] Furthermore, the flow channel cross-section of the first end 1111 is rectangular, with a width of 4.5mm-6.5mm and a height of 1.2mm-1.8mm; the flow channel cross-section of the second end 1112 is also rectangular, with a width of 1.8mm-3.3mm and a height of 1mm-1.3mm. The appropriate width and height of the flow channel cross-sections at both the first and second ends 1111 and 1112 can limit the flow rate of the culture medium within a certain range, thereby precisely controlling the flow rate of the culture medium injected into the culture tank 130. This shortens the medium change cycle and improves the medium change efficiency while avoiding adverse effects on the embryo.

[0037] Optionally, the second flow channel section 113 is funnel-shaped, with the cross-sectional area of ​​the fourth end 1132 being larger than that of the third end 1131. This allows the flow velocity of the culture medium to gradually decrease as it flows from the third end 1131 to the fourth end 1132, thereby slowing down the flow rate of the culture medium into the culture tank 130 and preventing any impact on embryo development within the culture tank 130. Furthermore, the larger cross-sectional area of ​​the fourth end 1132, which is connected to the culture tank 130, allows the culture medium in the second flow channel section 113 to achieve a more stable balance with the external atmospheric environment through the fourth end 1132.

[0038] Furthermore, the flow channel cross-section of the fourth end 1132 is rectangular, with a width of 4.5mm-6.5mm and a height of 1.2mm-1.8mm; the flow channel cross-section of the third end 1131 is also rectangular, with a width of 1.8mm-3.3mm and a height of 1mm-1.3mm. The appropriate width and height of the flow channel cross-sections of the third end 1131 and the fourth end 1132 can limit the flow rate of the culture medium within a certain range, thereby precisely controlling the flow rate of the culture medium injected into the culture tank 130. This shortens the medium change cycle and improves the medium change efficiency while avoiding adverse effects on the embryo.

[0039] In this embodiment, the width of the flow channel cross-section formed by the first end 1111 is the same as the width of the flow channel cross-section formed by the fourth end 1132, and the height of the flow channel cross-section formed by the first end 1111 is the same as the height of the flow channel cross-section formed by the fourth end 1132; the width of the flow channel cross-section formed by the second end 1112 is the same as the width of the flow channel cross-section formed by the third end 1131, and the height of the flow channel cross-section formed by the second end 1112 is the same as the height of the flow channel cross-section formed by the third end 1131, so as to facilitate processing and production, and to facilitate control of the flow rate of the culture medium from the storage tank 120 to the culture tank 130.

[0040] Optionally, the connecting channel section 112 is circular, and the cross-sectional area of ​​the connecting channel section 112 is larger than that of the second end 1112, and the cross-sectional area of ​​the connecting channel section 112 is larger than that of the third end 1131. The connecting channel section 112 is used to receive the culture medium flowing out from the second end 1112 and discharge the culture medium inside through the third end 1131. In this process, the connecting channel section 112 can play a buffering role to further slow down the flow rate of the culture medium and avoid adverse effects on the embryo.

[0041] As one possible implementation, the microfluidic channel 110 also includes a switching valve 114, which extends into the connecting flow channel section 112 and is used to adjust the flow rate of the culture medium to achieve precise control of the flow rate of the culture medium injected into the culture tank 130.

[0042] Specifically, the switching valve 114 includes a valve body 1141 and a baffle 1142 connected to each other. The valve body 1141 is rotatably engaged with the dish body 140, and the valve body 1141 can rotate relative to the dish body 140. The dish body 140 can limit the valve body 1141. The baffle 1142 is disposed in the connecting flow channel section 112. The valve body 1141 is used to drive the baffle 1142 to rotate relative to the connecting flow channel section 112, so as to adjust the size of the gap between the baffle 1142 and the side wall of the connecting flow channel section 112, thereby adjusting the flow rate of the culture medium through the connecting flow channel section 112. Specifically, when the valve body 1141 drives the baffle 1142 to rotate in a direction parallel to the flow direction of the culture medium, the gap between the baffle 1142 and the side wall of the connecting flow channel section 112 is at its maximum, and the flow rate of the culture medium through the connecting flow channel section 112 reaches its maximum; when the valve body 1141 drives the baffle 1142 to rotate in a direction perpendicular to the flow direction of the culture medium, the gap between the baffle 1142 and the side wall of the connecting flow channel section 112 is at its minimum, and the flow rate of the culture medium through the connecting flow channel section 112 is 0.

[0043] Furthermore, a locking part 1143 is provided at the end of the valve body 1141 away from the baffle 1142. The locking part 1143 is used to cooperate with the rotating component 1144 so that the rotating component 1144 and the locking part 1143 cooperate to provide torque to the valve body 1141, thereby driving the valve body 1141 to rotate, thereby realizing the precise rotation function of the baffle 1142, switching the on / off state of the connecting flow channel section 112 or adjusting the flow rate of the culture medium. Specifically, the rotating component 1144 is a torsion bar, a gear shaft, or a handwheel.

[0044] In this embodiment, the microfluidic channel 110 further includes a drive component (not shown). The drive component is connected to the valve body 1141 via a rotating component 1144. The drive component is used to drive the baffle 1142 to rotate through the valve body 1141, thereby realizing the electric drive of the switching valve 114 and further improving the flow rate control accuracy. Specifically, the drive component is a drive motor, a hydraulic motor, or a pneumatic motor.

[0045] As one possible implementation, the bottom wall of the culture tank 130 is provided with a micro-channel 131 and a washing tank 132. The micro-channel 131 and the washing tank 132 are spaced apart. The micro-channel 131 is used to place embryos to achieve in vitro embryo culture, while the washing tank 132 is used for temporary storage of embryos or for washing embryos, making it convenient and practical. Specifically, during the process of introducing culture medium into the culture tank 130, the culture medium will fill the micro-channel 131 and the washing tank 132. Embryos can then be placed in the micro-channel 131, temporarily stored in the washing tank 132, or placed in the washing tank 132 for washing.

[0046] Optionally, there are multiple accommodating microchannels 131, which are arranged in a rectangular array. Each accommodating microchannel 131 is used to place one embryo. The multiple accommodating microchannels 131 work together to achieve in vitro culture of multiple embryos at the same time, and the multiple embryos do not affect each other.

[0047] Optionally, there are multiple washing tanks 132, which are divided into two groups. The two groups of washing tanks 132 are arranged opposite each other on both sides of the receiving micro-channel 131 to reduce the distance between the washing tanks 132 and the receiving micro-channel 131, so as to facilitate the rapid transfer of embryos temporarily stored in the washing tanks 132 to the receiving micro-channel 131.

[0048] In this embodiment, the number of washing tanks 132 in each group is two, but it is not limited to this. In other embodiments, the number of washing tanks 132 in each group can be one or three. There is no specific limitation on the number of washing tanks 132 in each group.

[0049] Optionally, both the microchannel 131 and the washing tank 132 are inverted cone-shaped, meaning their cross-sectional areas gradually increase from bottom to top to facilitate placing the embryos within them. Specifically, after placing the embryos in the microchannel 131 or washing tank 132, because the density of the embryos is greater than that of the culture medium, the embryos will sink to the bottom of the microchannel 131 or washing tank 132. The bottom diameter of the microchannel 131 is slightly larger than the diameter of the embryos (approximately 200 μm - 400 μm) to prevent embryo loss due to misalignment during medium changes or embryo transfer.

[0050] Optionally, the bottom wall of the receiving microchannel 131 and the bottom wall of the washing tank 132 are located on the same horizontal plane, so that the stereoscope does not need to be refocused during the transfer of the embryo from the washing tank 132 to the receiving microchannel 131, thereby improving the transfer efficiency and reducing the transfer time of the embryo.

[0051] In this embodiment, both the storage tank 120 and the culture tank 130 are cylindrical. The volume of the storage tank 120 is larger than that of the culture tank 130. The capacity of the storage tank 120 is 1.8 mL-2.5 mL, and the capacity of the culture tank 130 is 1.3 mL-2 mL. Furthermore, since the microchannel 131 is required for embryo imaging observation, the height from the bottom wall of the microchannel 131 to the bottom surface of the dish 140 is limited to 1.6 mm-2.0 mm to adapt to the Hoffman imaging principle and ensure that the embryo has a three-dimensional shadow imaging effect. Furthermore, considering that the embryo dynamic culture dish 100 requires manual transfer of the embryo to the receiving micro-channel 131 using an operating needle before use, the distance between the receiving micro-channel 131 and the side wall of the culture pool 130 is limited to at least 7.5 mm, and the ratio of the distance between the receiving micro-channel 131 and the side wall of the culture pool 130 to the height of the side wall of the culture pool 130 is limited to at least 1 / 2, so that the manual needle angle during embryo transfer is less than 60°, preferably less than 45°, thereby improving operational efficiency.

[0052] In one possible implementation, the bottom wall of the culture tank 130 is stepped, with a first stepped wall 133 and a second stepped wall 134. The first stepped wall 133 is higher than the second stepped wall 134 and lower than the bottom wall of the storage tank 120. Specifically, a washing tank 132 is formed on the first stepped wall 133, a microchannel 131 is formed on the second stepped wall 134, and a microfluidic channel 110 is connected to the second stepped wall 134. The culture medium in the storage tank 120 can flow to the second stepped wall 134 through the microfluidic channel 110. Subsequently, the liquid level of the culture medium gradually rises and submerges the first stepped wall 133. During this process, the culture medium will sequentially fill the microchannel 131 formed on the second stepped wall 134 and the washing tank 132 formed on the first stepped wall 133.

[0053] Optionally, the first step wall 133 has an inverted conical curved surface. The end of the first step wall 133 near the second step wall 134 is lower than the end of the first step wall 133 away from the second step wall 134. The inverted conical curved surface of the first step wall 133 can make the culture medium at the end away from the second step wall 134 tend to flow into the second step wall 134, so that the culture medium can be gathered as much as possible in the second step wall 134. This can minimize the amount of waste liquid residue at the edge of the culture tank 130 when the waste liquid in the culture tank 130 is extracted.

[0054] Optionally, the second step wall 134 is provided with a stop post 135. The position of the stop post 135 corresponds to the outlet position of the microfluidic channel 110. The culture medium flowing out of the microfluidic channel 110 to the culture tank 130 will first flow to the side of the stop post 135. The side of the stop post 135 is used to stop the culture medium flowing out of the microfluidic channel 110, so as to reduce the turbulent velocity of the culture medium, thereby reducing the influence of wall shear force on the embryo and reducing the pressure stress response of the embryo during medium replacement.

[0055] Optionally, the top surface of the stop post 135 is an inclined surface, and the lowest point of the top surface of the stop post 135 is higher than the first step wall 133. The top surface of the stop post 135 is used to abut against the pipette tip to achieve the alignment of the pipette tip and to limit the descent height of the pipette tip. Specifically, during the process of using a pipette to extract waste liquid from the culture tank 130, it is necessary to control the pipette to descend until the pipette tip abuts against the top surface of the stop post 135. At this point, the top surface of the stop post 135, which has a certain height and is inclined, can prevent the pipette tip from completely emptying the waste liquid in the culture tank 130 (only 75%-80% will be extracted, leaving 20%-25%), thus avoiding adverse effects on the embryos. Furthermore, the lowest point of the top surface of the stop post 135 is higher than the first step wall 133, ensuring that the liquid level of the remaining waste liquid in the culture tank 130 is higher than the first step wall 133 when the liquid extraction is completed. This ensures that the oil layer on the surface of the waste liquid is higher than the first step wall 133, thereby preventing the oil layer from adhering to the first step wall 133 and causing the oil layer to fail to float naturally after replenishment, thus ensuring the oil covering effect.

[0056] Optionally, the bottom wall of the storage tank 120 is stepped, and the bottom wall of the storage tank 120 is provided with a third step wall 121 and a fourth step wall 122. The third step wall 121 is higher than the fourth step wall 122, and the fourth step wall 122 is higher than the first step wall 133. The microfluidic channel 110 is connected to the fourth step wall 122, and the culture medium in the storage tank 120 can flow from the third step wall 121 to the fourth step wall 122, and then flow to the microfluidic channel 110.

[0057] Specifically, the third step wall 121 has an inverted conical curved surface. The end of the third step wall 121 near the fourth step wall 122 is lower than the end of the third step wall 121 away from the fourth step wall 122. The inverted conical curved surface of the third step wall 121 allows the culture medium at the end away from the fourth step wall 122 to tend to flow into the fourth step wall 122, so that the culture medium can be gathered as much as possible in the fourth step wall 122. This can increase the flow rate of the culture medium from the storage tank 120 to the microfluidic channel 110 during medium replacement, thereby improving the medium replacement efficiency.

[0058] Furthermore, the third step wall 121 is provided with a limiting post 123. The top surface of the limiting post 123 is an inclined surface. The lowest point of the top surface of the limiting post 123 is higher than the highest point of the third step wall 121. The top surface of the limiting post 123 is used to abut against the pipette tip to achieve the alignment of the pipette tip and to limit the descent height of the pipette tip.

[0059] As one possible implementation, the embryo dynamic medium exchange culture dish 100 also includes a dish cover 150. The dish cover 150 is placed on the dish body 140 and is used to cover the reservoir 120 and the culture tank 130. The dish cover 150 has a first through hole 151, a clearance hole 152 and a second through hole 153; the first through hole 151 communicates with the reservoir 120 and is used for a pipette tip to pass through, so that the pipette tip can inject culture medium into the reservoir 120; the second through hole 153 communicates with the culture tank 130 and is used for a pipette tip to pass through, so that the pipette tip can extract waste liquid in the culture tank; the clearance hole 152 is used for a switch valve 114 to pass through, so as to realize the movable cooperation between the switch valve 114 and the dish body 140.

[0060] It is worth noting that the embryo dynamic medium exchange culture dish 100 has a method of use, which includes the following steps: Preparation of the culture medium: Open the switch valve 114 and inject the culture medium into the storage tank 120 so that the culture medium flows through the microfluidic channel 110 to the culture tank 130 until the liquid levels of the culture medium in the storage tank 120 and the culture tank 130 are equal. Then, perform oil covering treatment and reagent balancing.

[0061] It should be noted that a novel embryo dynamic medium exchange culture dish 100 is provided in the dish preparation step. First, the dish lid 150 is opened and the switch valve 114 is turned on. Then, the culture medium is injected into the reservoir 120 using a pipette. During this process, some of the culture medium flows to the culture tank 130 through the microfluidic channel 110 under the action of gravity, filling the containment micro-channel 131 and the washing tank 132. When the required amount of culture medium is injected, the injection is stopped. At this time, the liquid levels of the culture medium in the reservoir 120 and the culture tank 130 are equal. Then, the culture medium in the reservoir 120 and the culture tank 130 are coated with oil to form an oil layer on their surface. Next, the dish lid 150 is closed, and the entire embryo dynamic medium exchange culture dish 100 is placed in the incubator and left to stand for a period of time (usually more than 6 hours) to allow for reagent equilibration.

[0062] Sample addition: Transfer the embryos to culture tank 130.

[0063] It should be noted that in the preparation step, the embryo dynamic medium exchange culture dish 100 is first taken out of the incubator; then the embryos are transferred from the external culture dish to the washing tank 132 of the culture pool 130 for temporary storage and cleaning; after cleaning, the embryos in the washing tank 132 are transferred to the containing micro-tank 131; then the dish lid 150 is closed again, and the embryo dynamic medium exchange culture dish 100 is placed in the incubator for embryo culture.

[0064] Medium replacement: Close the switch valve 114, inject the culture medium into the storage tank 120, and perform reagent balancing. Then, extract the waste liquid in the culture tank 130 and open the switch valve 114 to allow the culture medium to flow to the culture tank 130 through the microfluidic channel 110.

[0065] It should be noted that after the sample is added, the culture medium in the culture tank 130 needs to be changed in a timely manner as required to ensure the embryo development effect. The number of medium changes needs to be determined according to the culture cycle, that is, several medium changes may be required throughout the entire culture cycle.

[0066] Specifically, in the medium replacement step, the embryo dynamic medium replacement culture dish 100 is first removed from the incubator; then the switch valve 114 is closed, and a certain amount of culture medium is injected into the storage tank 120 (the injection volume needs to be determined according to the medium replacement requirements); next, the embryo dynamic medium replacement culture dish 100 is placed in the incubator for reagent equilibration; after a preset time (6h-8h), the embryo dynamic medium replacement culture dish 100 is removed from the incubator; then, a large portion (75%-8%) of the waste liquid in the culture tank 130 is extracted using a pipette. At this point, the oil layer in culture tank 130 still floats on the remaining waste liquid. Next, valve 114 is opened, allowing the culture medium in storage tank 120 to flow naturally through microfluidic channel 110 to culture tank 130 under gravity, until the liquid levels in storage tank 120 and culture tank 130 are level again. During this process, the liquid level in culture tank 130 rises, causing the oil layer to rise, while the liquid level in storage tank 120 falls, causing the oil layer to fall. This achieves natural dynamic liquid exchange of embryos in the dynamic embryo culture dish 100 under the same environment, avoiding the impact of artificial embryo transfer and liquid exchange on the embryos, and ensuring the embryo development effect.

[0067] The microfluidic channel 110 provided in this embodiment of the invention has a first flow channel segment 111 with a first end 1111 and a second end 1112 disposed opposite to each other. The first end 1111 is used to communicate with the liquid storage tank 120, and the second end 1112 is connected to the connecting flow channel segment 112. The second flow channel segment 113 has a third end 1131 and a fourth end 1132 disposed opposite to each other. The third end 1131 is connected to the connecting flow channel segment 112, and the fourth end 1132 is used to communicate with the culture tank 130. When the microfluidic channel 110 is in use, the extension direction of the connecting flow channel segment 112 and the extension direction of the second flow channel segment 113 are both parallel to the horizontal plane. A preset angle is formed between the extension direction of the first flow channel segment 111 and the extension direction of the connecting flow channel segment 112, and the preset angle is 150 degrees to 180 degrees. Compared with existing technologies, the microfluidic channel 110 provided by this invention, due to its first flow channel section 111 inclined to the horizontal plane, a first end 1111 for communicating with the storage tank 120, and a fourth end 1132 for communicating with the culture tank 130, can achieve automatic replenishment of culture medium in the culture tank 130, saving time and effort, improving the control accuracy of the culture medium injection flow rate, shortening the medium change cycle, improving the medium change efficiency, and avoiding adverse effects on the embryo. This results in high medium change efficiency and good medium change effect in the embryo dynamic medium change culture dish 100.

[0068] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A microfluidic channel for communicating between a reservoir and a culture well for the flow of culture fluid from the reservoir to the culture well, characterized by, The microfluidic channel includes a first flow channel segment, a connecting flow channel segment, and a second flow channel segment connected in sequence. The first flow channel segment has a first end and a second end disposed opposite to each other. The first end is used to communicate with the liquid storage tank, and the second end is used to communicate with the connecting flow channel segment. The second flow channel segment has a third end and a fourth end disposed opposite to each other. The third end is used to communicate with the connecting flow channel segment, and the fourth end is used to communicate with the culture tank. When the microfluidic channel is in use, the extension directions of the connecting flow channel segment and the second flow channel segment are both parallel to the horizontal plane. A preset angle is formed between the extension directions of the first flow channel segment and the extension directions of the connecting flow channel segment, and the preset angle is 150 degrees to 180 degrees.

2. The microfluidic channel of claim 1, wherein, The first flow channel section is funnel-shaped, and the cross-sectional area of ​​the flow channel at the first end is larger than the cross-sectional area of ​​the flow channel at the second end.

3. The microfluidic channel of claim 2, wherein, The cross-section of the flow channel at the first end is rectangular, with a width of 4.5mm-6.5mm and a height of 1.2mm-1.8mm. And / or, the flow channel cross-section at the second end is rectangular, with a width of 1.8mm-3.3mm and a height of 1mm-1.3mm.

4. The microfluidic channel of claim 1, wherein, The second flow channel section is funnel-shaped, and the cross-sectional area of ​​the flow channel at the fourth end is larger than that at the third end.

5. The microfluidic channel of claim 2, wherein, The flow channel at the fourth end has a rectangular cross-section, with a width of 4.5mm-6.5mm and a height of 1.2mm-1.8mm. And / or, the flow channel cross-section of the third end is rectangular, and the width of the flow channel cross-section of the third end is 1.8mm-3.3mm, and the height is 1mm-1.3mm.

6. The microfluidic channel of claim 1, wherein, The connecting flow channel section is circular, and the cross-sectional area of ​​the connecting flow channel section is larger than the cross-sectional area of ​​the flow channel at the second end, and the cross-sectional area of ​​the connecting flow channel section is larger than the cross-sectional area of ​​the flow channel at the third end.

7. The microfluidic channel according to claim 1, characterized in that, The microfluidic channel also includes a switching valve, which extends into the communicating channel section and is used to regulate the flow rate of the culture medium.

8. The microfluidic channel according to claim 7, characterized in that, The switching valve includes a valve body and a baffle connected to each other. The baffle is disposed within the connecting flow channel section. The valve body is used to drive the baffle to rotate relative to the connecting flow channel section in order to adjust the size of the gap between the baffle and the side wall of the connecting flow channel section.

9. The microfluidic channel according to claim 8, characterized in that, The microfluidic channel also includes a drive component connected to the valve body, which is used to drive the baffle to rotate through the valve body.

10. A dynamic embryo culture dish, characterized in that, It includes a storage tank, a culture tank, and a microfluidic channel as described in any one of claims 1-9. The storage tank is connected to the first end, and the culture tank is connected to the fourth end. When the embryo dynamic fluid exchange culture dish is placed on a horizontal surface, the first end is higher than the second end, and the bottom of the storage tank is higher than the bottom of the culture tank.

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