PDMS blood vessel and preparation method thereof

Abstract

The invention provides a blood-like tube which comprises a tube body made of a PDMS base material, a tube cavity is defined by the tube body, a continuous-phase hole is formed in the tube body, and the continuous-phase hole is communicated with the tube cavity. The blood-like vessel provided by the invention has high uniformity and good biocompatibility, can be used for nutrient supply for three-dimensional organoid culture, and does not generate rejection reaction, and meanwhile, the preparation method of the blood-like vessel is simple and low in cost.

Description

Technical Field

[0001] This invention relates to the field of biomedical engineering. Specifically, this invention relates to a PDMS-like blood vessel and its preparation method. More specifically, this invention relates to a blood vessel and its uses, preparation method, and an organoid. Background Technology

[0002] Existing substrates for preparing blood vessel-like structures mainly fall into two categories: The first category consists of bioactive components, such as decellularized extracellular matrix (ECM) or in vitro cultured vascular endothelial cells. Blood vessels prepared from these components exhibit good biocompatibility and are considered to have strong clinical application prospects. Although the properties of the prepared blood vessels are similar to real blood vessels, the preparation process is difficult, time-consuming, and requires complex experimental conditions. The second category comprises non-biologically derived organic materials, including natural and synthetic polymers. Specifically, natural polymers include silk fibroin and elastin. While these substances have good biocompatibility, they are easily degraded in the cellular environment, making them unsustainable; they also lack sufficient mechanical strength, potentially leading to loss of structure and function. Synthetic polymers include polycaprolactone (PCL), expanded polytetrafluoroethylene (ePTFE), and hydrogels. For the second category of components, although the processing flow is simpler, the synthetic polymers generally have poor cell compatibility, and most degradation products have been shown to trigger adverse immune responses. Their surfaces also have limited resistance to thrombosis, which can lead to graft obstruction.

[0003] Similar to vascular substrates, existing tissue-engineered blood vessel fabrication methods mainly fall into two categories: The first relies on cell-on-scaffold shaping to create blood vessels. This involves first preparing an organic scaffold in vitro, then seeding cells onto the scaffold, and finally performing decellularization to remove immunogenic cellular antigens while retaining relatively non-immunogenic extracellular matrix components. Methods for scaffold fabrication include bioprinting, phase separation, and electrospinning. The second method relies on polymers to directly shape blood vessels, including template methods, weaving methods, and stretching methods.

[0004] However, these methods still have shortcomings in terms of controllability, mechanical strength, lumen size accuracy, and operability: the preparation cycle of cell-containing blood vessels is long and the experimental environment is highly demanding; electrospinning is difficult to obtain structures with stable hollow cavities; hydrogel printing is limited by material strength and it is difficult to maintain the perfusion environment for a long time; the pore size distribution obtained by phase separation is uneven, making it difficult to achieve the preparation of continuous blood vessel channels from millimeters to micrometers.

[0005] Currently, the substrates for blood vessel-like materials have issues such as biocompatibility and stability; at the same time, the preparation methods for blood vessel-like materials also suffer from problems such as poor convenience and high production costs. Therefore, there is a need for a blood vessel-like material that combines excellent biological and physicochemical properties, as well as a new method for preparing blood vessel-like materials that is simple to process, size controllable, and scalable. Summary of the Invention

[0006] This invention is based on the inventor's discoveries and understanding of the following facts and problems: PDMS possesses mild physicochemical properties, is highly resilient and flexible, ensuring it will not cause physicochemical damage to biological tissues. PDMS also exhibits good biocompatibility, failing to cause rejection reactions upon contact with animal tissues. Furthermore, PDMS demonstrates excellent gas permeability, allowing the passage of gases such as oxygen and carbon dioxide, a property well-suited to the function of material exchange in blood vessel-like structures. Therefore, PDMS is an excellent substrate for blood vessel-like structures.

[0007] Therefore, in a first aspect, the present invention proposes a blood vessel-like structure, comprising, according to an embodiment of the invention: a tube body, the tube body being constructed of a PDMS substrate, the tube body defining a lumen, and the tube body having pores of a continuous phase communicating with the lumen. The blood vessel-like structure proposed by the present invention exhibits high uniformity and good biocompatibility, and can be used for nutrient supply in three-dimensional organoid culture.

[0008] According to an embodiment of the present invention, the diameter of the lumen is 10 μm to 100 μm.

[0009] According to an embodiment of the present invention, the diameter of the lumen is 40 μm to 60 μm.

[0010] According to an embodiment of the present invention, the diameter of the pores in the continuous phase is 0.08 μm to 60 μm.

[0011] According to an embodiment of the present invention, the diameter of the pores in the continuous phase is 100 nm to 200 nm.

[0012] In a second aspect, the present invention provides a method for preparing the aforementioned blood vessel-like structures. According to an embodiment of the present invention, the method includes: performing a first mixing treatment on PDMS and a curing agent; performing a second mixing treatment on a sacrificial template and the first mixed product; placing the second mixed product in a container for positive suspension fixation; inserting a heating wire into the fixed second mixed product and subjecting it to an energizing treatment; and removing the energized heating wire and performing a sacrificial template removal treatment to obtain the blood vessel-like structures. The method proposed in this invention is simple, fast, low-cost, and highly repeatable; furthermore, the blood vessel-like structures prepared according to the method proposed in this invention exhibit high uniformity and good biocompatibility.

[0013] According to an embodiment of the present invention, the volume ratio of PDMS to curing agent is 10:1.

[0014] According to an embodiment of the present invention, the sacrificial template is a carbohydrate.

[0015] According to an embodiment of the present invention, the sugar is sucrose.

[0016] According to an embodiment of the present invention, the sucrose has a diameter of 40 μm to 50 μm.

[0017] According to an embodiment of the present invention, the volume ratio of sucrose to PDMS is 1:2.

[0018] According to an embodiment of the present invention, the sacrificial template is a linear ZnO crystal.

[0019] According to an embodiment of the present invention, the linear ZnO crystals are obtained by the following steps: subjecting zinc nitrate hexahydrate and hexamethylenetetramine to a third mixing treatment; subjecting the product of the third mixing treatment to a heat treatment; and subjecting the heat-treated product to a cooling treatment to obtain the linear ZnO crystals.

[0020] According to an embodiment of the present invention, the zinc nitrate hexahydrate and hexamethylenetetramine are mixed by magnetic stirring.

[0021] According to an embodiment of the present invention, the molar ratio of zinc nitrate hexahydrate to hexamethylenetetramine is 1:1.

[0022] According to an embodiment of the present invention, the heat treatment is carried out at a temperature of 80°C to 100°C.

[0023] According to an embodiment of the present invention, the heat treatment is carried out at a temperature of 90°C.

[0024] According to an embodiment of the present invention, the heating treatment time is 3 h to 5 h.

[0025] According to an embodiment of the present invention, the heat treatment time is 4 hours.

[0026] According to an embodiment of the present invention, the linear ZnO crystal has a diameter of 100 nm to 200 nm.

[0027] According to an embodiment of the present invention, the volume ratio of the linear ZnO crystal to PDMS is 1:1 to 1:10.

[0028] According to an embodiment of the present invention, the diameter of the heating wire is 10 μm to 100 μm.

[0029] According to an embodiment of the present invention, the diameter of the heating wire is 50 μm.

[0030] According to an embodiment of the present invention, the heating wire is made of one of copper-nickel alloy, nickel wire, or Ross alloy.

[0031] According to an embodiment of the present invention, the heating wire is made of a copper-nickel alloy.

[0032] According to an embodiment of the present invention, the energizing process is performed under the following conditions: the temperature of the heating wire is 650°C to 750°C, and the duration is 1 s to 6 s.

[0033] According to an embodiment of the present invention, the temperature of the heating wire is 700°C, and the duration is 2 s to 5 s.

[0034] In a third aspect, the present invention proposes the use of the aforementioned blood vessel-like structures in organoid culture. The organoids proposed in this invention can supply nutrients during organoid culture without causing rejection reactions, thereby improving the long-term survival rate of organoids.

[0035] According to embodiments of the present invention, the organoids include at least one of the following: brain, liver, kidney, intestine, heart, lung, pancreas, and tumor organoids.

[0036] In a fourth aspect, the present invention proposes an organoid, wherein, according to an embodiment of the invention, the organoid comprises the aforementioned blood vessel-like structures. The organoid proposed by the present invention has a good nutrient supply system and does not cause rejection reactions.

[0037] The beneficial effects of this invention are at least as follows: The blood vessel-like structures proposed in this invention have good biocompatibility and high uniformity, and can provide nutrients for organoid culture without causing rejection reactions. At the same time, the preparation method of the blood vessel-like structures is simple, fast, low-cost and highly reproducible. Therefore, it can be used in more tissue engineering and biomaterials research, or extended to industries such as large-scale three-dimensional tissue culture. Attached Figure Description

[0038] Figure 1 These are PDMS-type blood vessels prepared according to embodiments of the present invention.

[0039] Figure 2 This is an optical micrograph of a blood vessel-like structure according to an embodiment of the present invention.

[0040] Figure 3 This is a scanning electron microscope image of a blood vessel-like structure according to an embodiment of the present invention.

[0041] Figure 4 These are organoids cultured according to embodiments of the present invention. Detailed Implementation

[0042] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0043] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0044] To facilitate understanding of this invention, certain technical and scientific terms are specifically explained and described below. Unless otherwise expressly defined elsewhere in this document, all other technical and scientific terms used herein have the meanings commonly understood by one of ordinary skill in the art to which this invention pertains. These explanations and descriptions are provided solely for the purpose of facilitating understanding and should not be construed as limiting the scope of protection of this invention.

[0045] In this article, the term "vascular-like" refers to a tubular network formed in engineered tissues or organoids that mimics the structure and / or function of natural blood vessels.

[0046] In this article, the term "organoid" refers to tissue analogs formed by in vitro three-dimensional culture of adult stem cells or pluripotent stem cells, which can simulate real organs in terms of structure and function.

[0047] In this article, the term "positive suspension fixation" refers to suspending the mixture in a container in a sufficiently uniform manner and fixing its shape.

[0048] In this article, the term "sacrificial template" refers to a material or structure that is used as a temporary support or mold during the manufacturing process but is removed (sacrificed) after the final structure is formed.

[0049] In this paper, the term "continuous phase" refers to phases that are interconnected, run through the entire system, and form a network or framework. In this paper, "pores in continuous phase" refers to pore spaces that are interconnected and form a network structure.

[0050] In this article, the term "porosity" refers to the proportion of pore area to the total surface area of ​​the vascular-like structure.

[0051] The technical solution of this application is described in detail below: vascular In some embodiments of the present invention, a blood vessel-like structure is proposed. According to an embodiment of the present invention, it includes: a tube body made of PDMS substrate, the tube body defining a lumen, and continuous phase pores communicating with the lumen. The blood vessel-like structure proposed in this invention has a porous structure on its inner and outer walls, enabling more efficient material exchange. The porosity of the blood vessel-like structure can be close to that of human capillaries, for example, it can be adjusted to 0.01%~0.04%, 0.01%, 0.02%, 0.03%, or 0.04%. Simultaneously, the blood vessel-like structure exhibits high uniformity and good biocompatibility, making it suitable for nutrient supply in three-dimensional organoid culture.

[0052] According to embodiments of the present invention, the diameter of the lumen is 10 μm to 100 μm. Exemplarily, the diameter of the lumen is 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, or a range between any two of the above values. According to some preferred embodiments of the present invention, the diameter of the lumen is 40 μm to 60 μm.

[0053] According to embodiments of the present invention, the diameter of the pores in the continuous phase is 0.08 μm to 60 μm. Exemplarily, the diameter of the pores in the continuous phase is 0.08 μm, 0.1 μm, 0.12 μm, 0.14 μm, 0.16 μm, 0.18 μm, 0.2 μm, 0.22 μm, 40 μm, 42 μm, 44 μm, 46 μm, 48 μm, 50 μm, 55 μm, 60 μm, or a range between any two of the above values. According to some preferred embodiments of the present invention, the diameter of the pores in the continuous phase is 100 nm to 200 nm.

[0054] Preparation method In some embodiments of the present invention, a method for preparing the aforementioned blood vessel-like structures is proposed. According to embodiments of the present invention, the method includes: performing a first mixing treatment on PDMS and a curing agent; performing a second mixing treatment on a sacrificial template and the first mixed product; placing the second mixed product in a container for positive suspension fixation; inserting a heating wire into the fixed second mixed product and applying an electric current to fix PDMS on the surface of the heating wire; removing the heated wire after the electric current treatment and immersing it in isopropanol to remove uncured PDMS; and then performing a sacrificial template removal treatment to obtain the blood vessel-like structures. The method proposed in this invention can realize the preparation of multi-pore-scale blood vessel channels at the millimeter and micrometer scales through a template method; the operation process is simple, fast, low-cost, and highly repeatable; at the same time, the blood vessel-like structures prepared by the method proposed in this invention have high uniformity and good biocompatibility.

[0055] According to an embodiment of the present invention, the volume ratio of PDMS to curing agent is 10:1.

[0056] According to an embodiment of the present invention, the sacrificial template is a carbohydrate. Carbohydrates, as sacrificial templates, are low-cost, easy to remove, and have good biocompatibility.

[0057] According to an embodiment of the present invention, the sugar is sucrose.

[0058] According to embodiments of the present invention, the sucrose has a diameter of 40 μm to 50 μm. Exemplarily, the sucrose has diameters of 40 μm, 42 μm, 44 μm, 46 μm, 48 μm, and 50 μm.

[0059] According to an embodiment of the present invention, the volume ratio of sucrose to PDMS is 1:2.

[0060] According to an embodiment of the present invention, the sacrificial template is a linear ZnO crystal. The fabrication process of linear ZnO crystals is simple, allowing for the large-scale, low-cost preparation of ZnO nanostructures with regular morphology and uniform size, while also enabling selective removal under mild conditions.

[0061] According to an embodiment of the present invention, the linear ZnO crystals are obtained by the following steps: subjecting zinc nitrate hexahydrate and hexamethylenetetramine to a third mixing treatment; subjecting the product of the third mixing treatment to a heat treatment; and subjecting the heat-treated product to a cooling treatment to obtain the linear ZnO crystals. The diameter of the linear ZnO crystals is determined by the ratio of the two substances, and the higher the ratio of zinc nitrate hexahydrate to hexamethylenetetramine, the lower the diameter of the linear ZnO crystals.

[0062] According to an embodiment of the present invention, the zinc nitrate hexahydrate and hexamethylenetetramine are mixed by magnetic stirring.

[0063] According to an embodiment of the present invention, the molar ratio of zinc nitrate hexahydrate to hexamethylenetetramine is 1:1.

[0064] According to embodiments of the present invention, the amount of zinc nitrate hexahydrate used is 20 mM to 30 mM. Exemplarily, the amount of zinc nitrate hexahydrate used is 20 mM, 22 mM, 24 mM, 25 mM, 26 mM, 28 mM, 30 mM, or a range between any two of the above values. According to some preferred embodiments of the present invention, the amount of zinc nitrate hexahydrate used is 25 mM.

[0065] According to embodiments of the present invention, the amount of hexamethylenetetramine used is 20 mM to 30 mM. Exemplarily, the amount of hexamethylenetetramine used is 20 mM, 22 mM, 24 mM, 25 mM, 26 mM, 28 mM, 30 mM, or a range between any two of the above values. According to some preferred embodiments of the present invention, the amount of hexamethylenetetramine used is 25 mM.

[0066] According to embodiments of the present invention, the heat treatment is performed at a temperature of 80°C to 100°C. Exemplarily, the heat treatment temperature is 80°C, 85°C, 90°C, 95°C, 100°C, or a range between any two of the above values. According to some preferred embodiments of the present invention, the heat treatment is performed at a temperature of 90°C.

[0067] According to an embodiment of the present invention, the heating treatment time is 3 h to 5 h. Exemplarily, the heating treatment time is 3 h, 3.5 h, 4 h, 4.5 h, 5 h, or a range between any two of the above values. According to some preferred embodiments of the present invention, the heating treatment time is 4 h.

[0068] According to embodiments of the present invention, the linear ZnO crystal has a diameter of 100 nm to 200 nm. Exemplarily, the diameter of the linear ZnO crystal is 100 nm, 120 nm, 140 nm, 160 nm, 180 nm, or 200 nm.

[0069] According to embodiments of the present invention, the mixing volume ratio of the linear ZnO crystal to PDMS is 1:1 to 1:10. Exemplarily, the mixing volume ratio of the linear ZnO crystal to PDMS is 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, or 1:10.

[0070] According to embodiments of the present invention, the diameter of the heating wire is 10 μm to 100 μm. Exemplarily, the diameter of the heating wire is 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, or a range between any two of the above values. According to some preferred embodiments of the present invention, the diameter of the heating wire is 50 μm.

[0071] According to an embodiment of the present invention, the heating wire is made of one of copper-nickel alloy, nickel wire, or Ross alloy.

[0072] According to an embodiment of the present invention, the heating wire is made of a copper-nickel alloy.

[0073] According to embodiments of the present invention, the energizing process is performed under the following conditions: the temperature of the heating wire is 650°C to 750°C. Due to the electrothermal effect of the heating wire, PDMS is cured on the surface of the heating wire. Exemplarily, the temperature of the heating wire is 650°C, 675°C, 700°C, 725°C, 750°C, or a range between any two of the above values. According to some preferred embodiments of the present invention, the temperature of the heating wire is 700°C.

[0074] According to embodiments of the present invention, the duration of the power-on process is 1 s to 6 s. For example, the duration of the power-on process is 1 s, 2 s, 3 s, 4 s, 5 s, 6 s, or any range between any two of the above values. According to some preferred embodiments of the present invention, the duration of the power-on process is 2 s to 5 s, and more preferably 4 s.

[0075] Organoids and their culture applications In some embodiments of the present invention, the use of the aforementioned blood vessel-like structures in organoid culture is proposed. The organoids proposed in this invention have a porous structure, enabling efficient material exchange, supplying nutrients during organoid culture, and preventing rejection reactions, thereby improving the long-term survival rate of the organoids.

[0076] According to embodiments of the present invention, the organoids include at least one of the following: brain, liver, kidney, intestine, heart, lung, pancreas, and tumor organoids.

[0077] In some embodiments of the present invention, an organoid is proposed, which, according to an embodiment of the present invention, comprises the aforementioned blood vessel-like structures. The organoid proposed by the present invention has a good nutrient supply system, does not undergo rejection, and has the ability to survive for a long time.

[0078] Embodiments of the present invention will now be described in more detail, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0079] Example 1: Preparation of Blood Vessels ZnO was prepared using a hydrothermal method as a template: First, a mixed aqueous solution of 25 mM zinc nitrate hexahydrate and 25 mM hexamethylenetetramine was prepared and mixed with a magnetic stirrer. Then, the solution was heated in a water bath at 90°C for 4 hours. After removing and cooling the sample, the ZnO precipitate at the bottom was scraped off, yielding powdered ZnO linear crystals.

[0080] Preparation of PDMS-based vascular-like raw materials: PDMS and curing agent were mixed at a volume ratio of 10:1, followed by vacuuming. The prepared ZnO was incorporated into PMDS, mixed again, and vacuumed. The resulting mixture was stored at room temperature for later use.

[0081] PDMS Curing and Molding: The aforementioned mixture is placed upright and fixed in a syringe. Due to its high viscosity, it will not flow out of the syringe. A copper-nickel alloy heating wire, approximately 20 cm in length, is inserted into the syringe needle tip and then pulled out from the other end. A power source is connected to both ends of the heating wire, and the current is controlled at 0.3 A to 0.4 A for 2 to 4 seconds. Due to the electrothermal effect of the heating wire, the PDMS cures on the surface of the heating wire. The heating wire is then removed. A PDMS-like blood vessel is obtained, cured on the surface of the heating wire.

[0082] Obtaining the vessel-like structure: First, immerse the previously obtained heating wire in isopropanol to wash away the uncured PDMS. Then, transfer the heating wire to a 1 mol / L dilute nitric acid solution and let it stand overnight. The next day, remove the heating wire to obtain the porous PDMS vessel-like structure, as shown in the attached figure. Figure 1 As shown.

[0083] Example 2: Determination of structural parameters of blood vessels The diameter and pore density of the PDMS-like vessels prepared earlier were measured. The vessels were observed under a bright-field microscope, and the diameter was calculated based on the magnification. Furthermore, the pores on the vessels within the electron microscope area were counted using a scanning electron microscope. Specific experimental results are attached. Figure 2 and attached Figure 3 As shown, the PDMS-type blood vessel proposed in this invention has a diameter of 50 μm and a porosity of 0.02%.

[0084] Example 3: Stability Verification of Blood Vessel-Organoids 3D printing of culture chambers: The culture chambers that have been pre-modeled are manufactured using 3D printing.

[0085] Electrodes and blood vessel-like structures were constructed on the culture chamber: First, flexible electrodes were attached to the culture chamber, and then three prepared PDMS blood vessel-like structures were attached to the electrodes in parallel.

[0086] Organoid integration: Neural organoids were seeded onto the electrode surface. Then, culture medium was perfused into the blood vessel-like structures using a microfluidic device.

[0087] Specific experimental results are attached. Figure 4 As shown, the organoids survived well and no rejection reaction occurred, indicating that the blood vessels proposed in this invention can be used for nutrient supply to organoids without causing rejection reaction.

[0088] Comparative Example 1: Preparation of PDMS-like blood vessels using sucrose as a sacrificial material Screening experiment on the sucrose to PDMS ratio: Equal amounts of PDMS substrate and curing agent were taken, and the volume ratio of PDMS to sucrose was set to 1:1 and 1:1.5, respectively. The experimental results showed that an excessively high sucrose ratio prevented PDMS from being molded. Considering both the formation of the vascular-like structure and porosity, the optimal volume ratio of sucrose to PDMS was 1:1.

[0089] Comparative Example 2: Screening of heating wire energizing conditions A constant current source was used to output current ranging from 0.4 A to 0.6 A. The heating wire was made of nickel-chromium alloy and approximately 20 cm in length. The diameter of the PDMS-formed blood vessel-like structures was measured and recorded under different energizing conditions. Experimental results showed that when the heating wire was energized at 0.5 A, the PDMS blood vessel diameter was approximately 100 μm. At 0.6 A, the diameter was 200 μm or larger, preventing the formation of perforations on the surface by sucrose or linear ZnO crystals. At 0.4 A, the PDMS failed to solidify due to insufficient surface temperature of the heating wire. Therefore, the optimal conditions were determined to be a current of 0.5 A, a heating wire surface temperature of 650℃~750℃, and an energizing time of 4 seconds.

[0090] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0091] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0092] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0093] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A type of blood vessel, characterized in that, include: The tube body is made of PDMS substrate and defines a cavity. The tube body has holes for a continuous phase that communicate with the cavity.

2. The blood vessel-like structure according to claim 1, characterized in that, The diameter of the lumen is 10 μm to 100 μm; Preferably, the diameter of the lumen is 40 μm to 60 μm.

3. The blood vessel-like structure according to claim 1, characterized in that, The diameter of the pores in the continuous phase is 0.08 μm to 60 μm; Optionally, the diameter of the pores in the continuous phase is 100 nm to 200 nm; Optionally, the porosity of the vascular-like structure is 0.01% to 0.04%, preferably 0.02%.

4. A method for preparing the blood vessel-like structure according to any one of claims 1 to 3, characterized in that, include: The PDMS and curing agent are first mixed. The sacrificial template is then subjected to a second mixing treatment with the first mixing product. The second mixed product is placed in a container for positive suspension fixation. The heating wire is inserted into the fixed second mixed product and then energized. After the heated wire has been energized, it is removed and subjected to a sacrificial template removal process to obtain the blood vessel-like structure.

5. The method according to claim 4, characterized in that, The volume ratio of the PDMS substrate to the curing agent is 10:

1.

6. The method according to claim 4, characterized in that, The sacrificial template is a carbohydrate; Preferably, the sugar is sucrose.

7. The method according to claim 6, characterized in that, The sucrose has a diameter of 40 μm to 50 μm; Optionally, the volume ratio of sucrose to PDMS is 1:

2.

8. The method according to claim 4, characterized in that, The sacrificial template is a linear ZnO crystal.

9. The method according to claim 8, characterized in that, The linear ZnO crystals are obtained through the following steps: Zinc nitrate hexahydrate and hexamethylenetetramine were subjected to a third mixing treatment; The third mixed product is then subjected to heat treatment; The heat-treated product is cooled to obtain the linear ZnO crystals.

10. The method according to claim 9, characterized in that, The zinc nitrate hexahydrate and hexamethylenetetramine were mixed by magnetic stirring. Optionally, the molar ratio of zinc nitrate hexahydrate to hexamethylenetetramine is 1:1; Optionally, the heat treatment is carried out at a temperature of 80°C to 100°C; Preferably, the heat treatment is carried out at a temperature of 90°C; Optionally, the heat treatment time is 3 h to 5 h; Preferably, the heat treatment time is 4 hours.

11. The method according to claim 8, characterized in that, include: The diameter of the linear ZnO crystal is 100 nm to 200 nm. Optionally, the mixing volume ratio of the linear ZnO crystal to PDMS is 1:1 to 1:

10.

12. The method according to claim 4, characterized in that, The diameter of the heating wire is 10 μm to 100 μm; Preferably, the diameter of the heating wire is 50 μm; Optionally, the heating wire is made of one of copper-nickel alloy, nickel wire, or Ross alloy; Preferably, the heating wire is made of a copper-nickel alloy.

13. The method according to claim 4, characterized in that, The power-on process is performed under the following conditions: Optionally, the temperature of the heating wire is 650℃~750℃, and the duration is 1 s~6 s; Preferably, the temperature of the heating wire is 700℃, and the duration is 2 s to 5 s.

14. The use of the blood vessel-like structures according to any one of claims 1 to 13 in organoid culture; Optionally, the organoids include at least one of the following: brain, liver, kidney, intestine, heart, lung, pancreas, and tumor organoids.

15. An organoid, characterized in that, The organoids comprise the blood vessel-like structures described in claims 1 to 13.

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