Embryological culture dish for inhibiting evaporation of culture medium

Abstract

The utility model belongs to embryo culture technical field especially relates to a kind of embryo culture dish of inhibiting culture medium evaporation. Including body, the culture cavity is equipped on the body, the micropore for limiting blastula movement is equipped in the culture cavity, culture medium is equipped in the culture cavity, sealing oil is equipped on the culture medium;The body further includes evaporation cavity, evaporation liquid is equipped in the evaporation cavity;Blastula is cultured in culture dish, evaporation liquid in the evaporation cavity evaporates, to improve the humidity of the outer space of sealing oil in the culture cavity, to inhibit the volatilization amount of the culture medium through sealing oil. Realized without needing to improve the overall humidity of incubator effectively slow down culture medium moisture loss, keep osmotic pressure relatively stable, to provide more stable and reliable culture microenvironment for blastula.

Description

Technical Field

[0001] This invention belongs to the field of embryo culture technology, and specifically relates to an embryo culture dish that inhibits the evaporation of culture medium. Background Technology

[0002] In assisted reproductive technologies, in vitro embryo culture is highly sensitive to temperature, gas composition, pH, and osmotic pressure. Currently, the commonly used microdrop culture method involves adding a small amount of culture medium to the wells of a petri dish and covering it with mineral oil or paraffin oil to slow down water evaporation and maintain a stable culture environment. However, because the culture medium is extremely small, even a trace loss of water can lead to an increase in osmotic pressure, affecting embryo development.

[0003] The article "Controversies in ART: considerations and risks for uninterrupted embryo culture" published in Volume 39, Issue 1 of Reproductive Biomedicine Online in 2019 points out that oil sealing cannot completely prevent water loss, and osmotic pressure and pH value will still increase as the culture time progresses.

[0004] The journal *Assisted Reproduction and Genetics*, Volume 36, 2019, article titled "Unstable osmolality of microdrops cultured in non-humidified incubators," demonstrated through experiments that even with an oil layer covering the culture medium, the osmolality of the culture medium is difficult to maintain in the long term under non-humidified conditions. The journal *Human Reproduction*, Volume 36, Issue 3, 2021, article titled "Factors of the human embryo culture system that may affect media evaporation and osmolality," pointed out that factors such as culture dish structure design, oil layer thickness, and incubator humidity have a significant impact on osmolality changes. Issue 5, article titled "Toward a predictive theoretical model for osmolality rise with non-humidified incubation: a randomized, multivariate response-surface study," showed that even with oil sealing, the stability of the culture medium is difficult to guarantee in the long term under dry conditions.

[0005] In time-lapse incubators, a low humidity level needs to be maintained to facilitate the operation of the sophisticated equipment used in time-lapse photography. However, under these conditions, even if the culture dishes are sealed with oil, the culture medium may still evaporate through the oil seal, causing changes in its concentration and thus hindering the normal culture of blastocysts. Utility Model Content

[0006] The purpose of this invention is to address the shortcomings of the aforementioned background technology and provide an embryo culture dish that inhibits the evaporation of the culture medium.

[0007] The technical solution adopted in this utility model is: an embryo culture dish for culturing blastocysts that inhibits the evaporation of culture medium, comprising a body, wherein the body is provided with a culture cavity, the culture cavity is provided with micropores for restricting the movement of the blastocyst, the culture cavity is provided with culture medium, and the culture medium is provided with sealing oil; the body also includes an evaporation cavity, wherein the evaporation cavity is provided with evaporating liquid; when the blastocyst is cultured in the culture dish, the evaporating liquid in the evaporation cavity evaporates to increase the humidity of the space outside the sealing oil in the culture cavity, thereby inhibiting the evaporation of the culture medium through the sealing oil.

[0008] Furthermore, the body also includes a first partition, which is disposed between the culture chamber and the evaporation chamber. This structure ensures that the liquid levels of the culture medium and sealing oil, as well as the liquid level of the evaporating liquid in the evaporation chamber, are all controlled below the top surface of the first partition, preventing direct contact between the sealing oil and the evaporating liquid, thereby reducing the risk of cross-contamination.

[0009] Furthermore, it also includes a dish lid, which fits onto the main body, so that the culture chamber and the evaporation chamber together form a single integrated chamber. By covering the culture dish with the lid, the temperature and humidity within the chamber are stabilized, and external contaminants are effectively reduced from entering the culture area.

[0010] Furthermore, the first partition is lower in height than the opening edge of the culture chamber formed by the body. This structure allows water vapor generated during the evaporation of the liquid in the evaporation chamber to smoothly enter the space above the culture chamber, increasing and equalizing the humidity outside the sealing oil layer inside the culture chamber, thereby inhibiting the evaporation of the culture medium through the sealing oil and maintaining the stability of the culture environment.

[0011] Furthermore, the culture chamber is provided with multiple culture wells and a strip-shaped groove, with each culture well located at the bottom of the groove. Multiple micropores are also provided, each located at the bottom of one of the culture wells. This structure allows for the separate positioning and independent culture of multiple blastocysts within the same culture chamber, reducing the amount of culture medium used in a single culture well and minimizing interference between blastocysts.

[0012] Furthermore, the micropores are located at the center of the bottom of the culture well. This structure isolates the blastocyst from liquid surface disturbance, thereby providing a stable positioning environment for the blastocyst and facilitating subsequent observation and manipulation.

[0013] Furthermore, the main body is also provided with a needle washing tank, which is located inside the culture chamber. This structure allows for in-situ cleaning of pipettes or micromanipulation needles within the same culture dish, reducing the risk of contamination from transferring needles between different dishes and improving operational efficiency. It also serves as a temporary placement area for embryos, facilitating short-term storage between different operational steps and reducing the time embryos are exposed to the external environment and the risk of contamination.

[0014] Furthermore, the number of needle washing tanks is two. This structure allows the two tanks to be used for different cleaning steps or separately for cleaning the operating needle and temporarily placing the embryo, thereby improving the flexibility and safety of the micromanipulation process and further reducing the risk of cross-contamination and embryo exposure.

[0015] Furthermore, there are two first partitions and two evaporation chambers, with the first partitions separating the two evaporation chambers from the culture chamber. This structure allows for the arrangement of evaporation chambers on both sides of the culture chamber to increase the total amount of evaporating liquid and the evaporation area, thereby maintaining a stable humidity environment for a longer period and ensuring balanced and stable culture conditions.

[0016] Furthermore, the culture chamber is provided with two strip-shaped grooves, each containing four culture wells evenly distributed, and each culture well has a corresponding micropore at its bottom. This structure allows for the regular arrangement and independent culture of at least eight blastocysts within a single culture dish, facilitating batch operation and numbering management while ensuring consistent culture conditions across all wells.

[0017] The beneficial effects of this invention are as follows: By integrating an evaporation chamber inside the culture dish, compared to the existing technology that relies solely on oil sealing to inhibit culture medium evaporation, this invention constructs an embryo culture dish structure with internal automatic humidification. This can more effectively inhibit water loss and osmotic pressure increase in the culture medium, and improve the stability of in vitro embryo culture. This invention locks the water vapor from the evaporating liquid inside the culture dish, thus avoiding the impact of external humidity changes on precision equipment and strengthening the oil sealing effect inside the culture dish, effectively inhibiting culture medium evaporation and creating a more favorable environment for blastocyst culture. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a three-dimensional structural diagram of Embodiment 1 of the present utility model; Figure 2 This is a top view of Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the structure of the dish lid of this utility model; Figure 4 This is a schematic diagram of the structure of the culture well of this utility model; Figure 5 This is a schematic diagram of the internal structure of the present invention in actual use; Figure 6 This is a three-dimensional structural diagram of Embodiment 2 of the present invention; Figure 7 This is a top view of Embodiment 2 of the present invention; Figure 8 This is a three-dimensional structural diagram of Embodiment 3 of the present invention; Figure 9 This is a schematic diagram of the internal structure of Embodiment 3 of the present invention; Figure 10 This is a three-dimensional structural diagram of Embodiment 4 of the present invention; Figure 11 This is a top view of Embodiment 4 of the present invention; Figure 12 This is a schematic diagram of the internal structure of Embodiment 4 of this utility model.

[0020] In the figure: 1-body; 2-culture chamber; 3-micropore; 4-culture medium; 5-sealing oil; 6-evaporation chamber; 7-evaporation liquid; 8-first partition; 9-plate lid; 10-strip groove; 11-culture well; 12-needle washing groove; 13-second partition; 14-third partition. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be further described in detail below with reference to the accompanying drawings. Figures 1 to 12 As shown, this utility model embodiment provides an embryo culture dish that inhibits the evaporation of culture medium, aiming to solve the problem in the prior art that even under dry conditions outside the oil seal, moisture may still slowly dissipate through the oil phase, making it difficult to stabilize the culture conditions.

[0022] Example 1: like Figures 1-5 As shown, an embryo culture dish for inhibiting culture medium evaporation includes a body 1. The body 1 has a culture chamber 2, and the culture chamber 2 has micropores 3 for restricting blastocyst movement. The culture chamber 2 contains culture medium 4, and the culture medium 4 is covered with sealing oil 5. The body 1 also includes an evaporation chamber 6, and the evaporation chamber 6 contains evaporating liquid 7. When the blastocyst is cultured in the culture dish, the evaporating liquid 7 in the evaporation chamber 6 evaporates to increase the humidity of the space outside the sealing oil 5 in the culture chamber 2, thereby inhibiting the evaporation of culture medium 4 through the sealing oil 5.

[0023] The rim of the opening of the main body 1 circumferentially mates with the lid 9, so that after the lid 9 is closed, the culture chamber 2 and the evaporation chamber 6 together form an integral chamber. A first partition 8 is positioned between the culture chamber 2 and the evaporation chamber 6, ensuring that the liquid levels of the culture medium 4 and sealing oil 5, as well as the liquid level of the evaporating liquid 7 in the evaporation chamber 6, are all below the height of the top surface of the first partition 8. The top surface of the first partition 8 is lower than the rim of the opening of the main body 1. The inner surface of the lid 9, together with the openings of the culture chamber 2 and the evaporation chamber 6, and the top surface of the first partition 8, form an integral chamber, and a gas channel connecting the culture chamber 2 and the evaporation chamber 6 is formed above the first partition 8.

[0024] During the cultivation process, the evaporating liquid 7 in the evaporation chamber 6 gradually evaporates due to the temperature of the chamber. The resulting water vapor diffuses through the gas channel to the space above the cultivation chamber 2, increasing the humidity outside the sealing oil 5 and thus inhibiting the evaporation of the culture medium 4 through the sealing oil 5. To prevent the liquids in the two chambers from overflowing and mixing, the liquid levels of the culture medium 4 and sealing oil 5 in the cultivation chamber 2, as well as the liquid level of the evaporating liquid 7 in the evaporation chamber 6, are all controlled to be below the top surface of the first partition 8. This keeps the cultivation chamber 2 and the evaporation chamber 6 isolated at the liquid level, communicating only at the gas level, in order to maintain the relative humidity inside the cultivation chamber 2.

[0025] The culture chamber 2 contains two strip-shaped grooves 10, which are arranged side by side along the width of the body 1. At least four culture wells 11 are spaced apart along the length of each strip-shaped groove 10, thus forming at least eight independent blastocyst culture sites in a culture dish. A micropore 3, smaller in diameter than the culture well 11, is located at the center of the bottom of each culture well 11. This micropore 3 is used to hold the blastocyst at the center of the bottom of the micropore 3. The double-layer structure of the micropore 3 and the culture well 11 prevents the blastocyst from moving during culture and effectively isolates it from liquid surface disturbance, thereby ensuring stable development of the blastocyst during culture.

[0026] During use, the operator first preheats the culture dish to the set temperature, then adds a predetermined amount of evaporating solution 7 to the evaporation chamber 6. This predetermined amount should be sufficient to meet the evaporation requirements throughout the entire culture period. The evaporating solution 7 can be distilled water or prepared culture medium 4. When distilled water is used, it evaporates slowly during culture and diffuses through the upper channel to the space above the culture chamber 2, providing humidity replenishment to the culture dish. When culture medium 4 is used as the evaporating solution 7, it can increase humidity and also be used for initial needle rinsing or temporary placement of blastocysts when needed. However, as the culture time progresses, the moisture in the culture medium 4 in the evaporation chamber 6 continuously dissipates, and the solute concentration gradually increases, leading to significant changes in osmotic pressure and component ratios. At this point, the culture medium in the evaporation chamber 6 can only continue to serve as a humidity source and should not be used for cleaning the operating needle or for direct contact with the blastocysts, to avoid adverse effects of concentrated culture medium on the blastocysts.

[0027] Then, an appropriate amount of culture medium 4 is added to the culture chamber 2, ensuring that each culture well 11 and microwell 3 is completely filled with the culture medium 4, spreading into a continuous liquid layer at the bottom of the culture chamber 2. After the culture medium 4 is laid, the operator precisely places the blastocyst into the center of the bottom of the microwell 3 under a microscope. Finally, sealing oil 5 is slowly dripped on top of the culture medium 4 until the sealing oil 5 completely covers the liquid surface of the culture medium 4 and forms a continuous oil layer in the culture chamber 2. The thickness of the oil layer is sufficient to cover the surface of the culture medium 4, reducing water evaporation and blocking the influence of external gas changes on the culture medium 4. After completing the above operations, the dish lid 9 is closed to the rim of the main body 1, so that the culture chamber 2 and the evaporation chamber 6 together form a chamber. During the culture process, the evaporating liquid 7 in the evaporation chamber 6 continues to evaporate, and water vapor is replenished to the space above the culture chamber 2 through the gas channel, forming a high humidity environment together with the external gas of the sealing oil 5, effectively inhibiting the evaporation of the culture medium 4 through the sealing oil 5 and slowing down the changes in osmotic pressure.

[0028] Example 2: like Figures 6-7 As shown, the body 1 forms a needle washing tank 12 in the central region of the culture chamber 2. The opening of the needle washing tank 12 faces upward and is used to clean pipettes or operating needles. Two needle washing tanks 12 are provided, symmetrically arranged in front of the strip groove 10, which facilitates the operator to directly complete needle washing and temporary placement of blastocysts within the microscopic operating field of view.

[0029] In use, culture medium 4 is first added to culture chamber 2, filling the microwells 3 and culture wells 11 and spreading into a continuous liquid layer at the bottom of culture chamber 2. This ensures that areas such as the strip groove 10 and the needle washing groove 12 are covered with culture medium 4, but sealing oil 5 has not yet been added. The operator inserts a pipette or micromanipulation needle into the needle washing groove 12 for cleaning, allowing residual culture medium 4 and impurities on the needle tip to be carried away by the culture medium 4 in the groove. When blastocyst transfer is required, the blastocyst can be briefly placed in the culture medium 4 in the needle washing groove 12 before being transferred to the target microwell 3. Only culture medium 4 is added to the needle washing groove 12; distilled water or other solutions are not added to avoid stress reactions in the blastocyst caused by frequent switching between different liquids.

[0030] After completing the needle washing and blastocyst transfer operations, the blastocysts are positioned in their respective microwells 3. Sealing oil 5 is then slowly dripped onto the culture medium 4 until it completely covers the surface of the culture medium 4 and forms a continuous oil layer within the culture chamber 2. The needle washing operation is completed before adding the sealing oil 5.

[0031] During micromanipulation, the operator can flexibly switch between the needle washing tank 12 and each culture well 11. After completing the aspiration or release operation in a culture well 11, the operating needle is moved to the needle washing tank 12 for cleaning to remove the culture medium 4 and any impurities that may be trapped on the needle tip. If necessary, a fine washing can be performed in another needle washing tank 12 before returning to the next culture well 11 to continue the operation. In this way, the operating needle can complete both coarse and fine washing within the body 1, reducing the possibility of residual culture medium 4 or impurities from the previous culture well 11 being carried into the next culture well 11, reducing the risk of cross-contamination between different blastocysts, and also helping to maintain a relatively stable composition and osmotic pressure of the liquid environment within the culture dish.

[0032] Evaporation chambers 6 are respectively arranged on both sides of the culture chamber 2, and each evaporation chamber 6 is separated from the culture chamber 2 by two first partitions 8. By arranging evaporation chambers 6 on both sides of the culture chamber 2, the total amount of evaporation liquid 7 and the effective evaporation surface area can be increased, thereby maintaining a stable high-humidity environment over a longer culture period. At the same time, two strip grooves 10 are arranged in the culture chamber 2, and at least eight culture wells 11 are evenly arranged in each strip groove 10, so that multiple blastocysts can be independently cultured and uniformly controlled in the same culture dish, which facilitates batch operation and management. Through the above structure and usage, the embryo culture dish of this utility model integrates multiple functions such as separate culture, internal humidification, on-site needle washing, and short-term storage of blastocysts in the same vessel, significantly improving the environmental stability and operational safety during the in vitro culture of blastocysts. The remaining structure and operation steps are the same as those in the aforementioned embodiments.

[0033] Example 3: like Figures 8-9As shown, in one embodiment, a first partition 8 is disposed between the culture chamber 2 and the evaporation chamber 6. The first partition 8 extends forward from one side of the inner wall of the body 1, then folds to the other side, and then returns to the inner wall of the body 1 along that side, forming a U-shaped structure. It separates the liquid areas of the culture chamber 2 and the evaporation chamber 6 in a plane, and controls the liquid levels of the culture medium 4 and the sealing oil 5, as well as the liquid level of the evaporating liquid 7 in the evaporation chamber 6, to be below the height of the top surface of the first partition 8, communicating only in the gas layer above the first partition 8.

[0034] During the cultivation process, the evaporating liquid 7 can be distilled water or prepared culture medium 4. The evaporating liquid 7 evaporates slowly in the evaporation chamber 6 and diffuses into the cultivation chamber 2 inside through the gas channel above the first partition 8, so that the cultivation chamber 2 can obtain a relatively uniform humidity supply around its perimeter. The Z-shaped first partition 8 forms a continuous partition on the liquid level, isolating the liquid areas of the cultivation chamber 2 and the evaporation chamber 6 from each other, preventing the culture medium 4 and sealing oil 5 from flowing into the evaporation chamber 6 across the first partition 8, or the evaporating liquid 7 from flowing into the cultivation chamber 2 across the first partition 8, thereby preventing the liquids in the two chambers from mixing and improving the humidification efficiency and the uniformity of humidity distribution. The remaining structure and operating steps are the same as in the aforementioned embodiment.

[0035] Example 4: like Figures 10-12 As shown, in this embodiment, a second partition 13 is provided on the outer side of each of the two needle washing tanks. A third partition 14 is provided between the two needle washing tanks 12. The top surface of the first partition 8 is lower than the edge of the opening of the main body 1, the height of the second partition 13 is flush with the edge of the opening of the main body 1, and the third partition 14 is slightly higher than the first partition 8.

[0036] The needle washing area is formed by the first partition 8, the second partition 13, the third partition 14, and the circumferential sidewalls of the main body 1, separating the liquid area containing the two needle washing tanks 12 from the remaining culture area of ​​the culture chamber 2. After the dish lid 9 is closed, the inner surface of the dish lid 9, the openings of the culture chamber 2, the evaporation chamber 6, and the needle washing area, as well as the top surfaces of the first partition 8 and the third partition 14, together form an integral chamber. A gas channel connecting the culture chamber 2, the evaporation chamber 6, and the needle washing area is formed above each of the first partition 8 and the third partition 14.

[0037] In use, the culture medium 4 in the needle washing area can also be utilized in conjunction with the humidification scheme described in the previous embodiments. The culture medium 4 in one side of the needle washing tank 12 can be used exclusively for cleaning the operating needle or for coarse washing, while the culture medium 4 in the other side of the needle washing tank 12 can be used exclusively for fine washing or short-term temporary storage of blastocysts. After the operation is completed, the culture medium 4 in the needle washing tank 12 is not sealed with oil, so that the culture medium 4 in the needle washing area can continue to evaporate and humidify as an evaporating liquid in subsequent culture stages. This reduces the amount of sealing oil 5 used while ensuring the humidity inside the cavity, saving consumable costs. The remaining structure and operating steps are the same as in the previous embodiments.

[0038] In summary, this invention establishes independent culture chambers and evaporation chambers on the same culture dish body, separated by a first partition while maintaining communication at the gas level. The continuous evaporation of the liquid within the evaporation chamber creates a locally high-humidity environment outside the sealing oil, effectively suppressing the slow evaporation of the culture medium and the resulting changes in osmotic pressure. Simultaneously, the culture chamber incorporates strip grooves, multiple culture wells, and micropores at the bottom of the wells, enabling regular separation and centered positioning of blastocysts for culture. Optional paired needle washing troughs facilitate needle cleaning and short-term blastocyst transfer within the same dish, reducing the risk of cross-dish handling and contamination, thereby improving the stability and consistency of the embryo culture environment and the reliability of the operation.

[0039] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains. The terms “first,” “second,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “comprising” or “including” and similar terms mean that the elements or objects preceding “comprising” or “including” encompass the elements or objects listed following “comprising” or “including” and their equivalents, and do not exclude other elements or objects. The terms “connected” or “linked” and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” and “right” are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0040] The above description is only an optional embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An embryo culture dish that inhibits culture medium evaporation for culturing blastocysts, characterized in that, include: The body (1) is provided with a culture chamber (2), the culture chamber (2) is provided with micropores (3) for restricting the movement of the blastocyst, the culture chamber (2) is provided with a culture medium (4), and the culture medium (4) is provided with sealing oil (5). The main body (1) also includes an evaporation chamber (6), and the evaporation chamber (6) contains an evaporating liquid (7). When the blastocyst is cultured in a culture dish, the evaporating liquid (7) in the evaporation chamber (6) evaporates to increase the humidity of the space outside the sealing oil (5) in the culture chamber (2), thereby inhibiting the amount of culture medium (4) volatilized through the sealing oil (5).

2. The embryo culture dish for inhibiting culture medium evaporation according to claim 1, characterized in that: The main body (1) also includes a first partition (8), which is disposed between the culture chamber (2) and the evaporation chamber (6).

3. The embryo culture dish for inhibiting culture medium evaporation according to claim 1, characterized in that: It also includes a dish lid (9), which is placed on the body (1) so that the culture chamber (2) and the evaporation chamber (6) together form an integral chamber.

4. The embryo culture dish for inhibiting culture medium evaporation according to claim 2, characterized in that: The first partition (8) is lower in height than the opening edge of the culture chamber (2) formed by the body (1).

5. An embryo culture dish for inhibiting culture medium evaporation according to claim 1, characterized in that: The culture chamber (2) is provided with multiple culture holes (11) and a strip groove (10). The multiple culture holes (11) are all located at the bottom of the strip groove (10). The micropores (3) are also provided, and the multiple micropores (3) are respectively located at the bottom of the culture holes (11).

6. An embryo culture dish for inhibiting culture medium evaporation according to claim 5, characterized in that: The micropore (3) is located at the bottom center of the culture well (11).

7. An embryo culture dish for inhibiting culture medium evaporation according to claim 1, characterized in that: The main body (1) is also provided with a needle washing groove (12), which is located inside the culture chamber (2).

8. An embryo culture dish for inhibiting culture medium evaporation according to claim 7, characterized in that: The number of the needle washing tanks (12) is two.

9. An embryo culture dish for inhibiting culture medium evaporation according to claim 2, characterized in that: There are two first partitions (8) and two evaporation chambers (6). The first partitions (8) separate the two evaporation chambers (6) from the culture chamber (2).

10. An embryo culture dish for inhibiting culture medium evaporation according to claim 5, characterized in that: The culture chamber (2) is provided with two strip grooves (10), and each strip groove (10) is provided with four culture holes (11) evenly arranged, and each culture hole (11) is provided with a corresponding micropore (3) at the bottom.

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