Medical repair material, preparation method and medical transplantation bag

Abstract

The application relates to the field of biological medical technology, in particular to a medical repair material, a preparation method and a medical transplantation bag. The method comprises the following steps: providing a piezoelectric elastomer and polylactic acid fibers; mixing dichloromethane and N,N-dimethylformamide to obtain a first solution; using dichloromethane as a second solution; providing a first syringe, dissolving the piezoelectric elastomer in the first solution, and then adding the piezoelectric elastomer into the first syringe; providing a second syringe, adding the second solution into the second syringe, and dissolving the piezoelectric elastomer in the second solution; respectively performing electrospinning treatment on the first syringe and the second syringe, so that the output end of the first syringe discharges piezoelectric fiber membranes, and the output end of the second syringe discharges fiber skeletons; and sequentially performing drying treatment and annealing treatment on the piezoelectric fiber membranes attached to the fiber skeletons to obtain the medical repair material. The piezoelectric material with high modulus can be well attached to organs during organ transplantation and organ formation.

Description

[Technical Field]

[0001] This invention relates to the field of biomedical technology, and in particular to a medical repair material, its preparation method, and a medical transplant bag. [Background Technology]

[0002] Piezoelectric materials have been found to accelerate the healing of wounds, muscle and tendon defects through effective in-situ electrical stimulation. Therefore, they are widely used in the medical field as biomedical materials.

[0003] Current organ transplantation techniques typically involve applying electrical stimulation to the nerve tissue within the organ to promote organ function recovery. Piezoelectric materials can be used to fabricate monitors that continuously monitor the organ's physiological parameters during transplantation, helping doctors monitor the transplanted organ's condition in real time. Furthermore, these monitors can also release electrical signals to stimulate the organ's nerves, further promoting organ function recovery.

[0004] However, the high elastic modulus of existing piezoelectric materials limits their use in organ transplantation to simply monitoring and providing electrical signals; they cannot effectively adhere to the organ to aid in the transplant process. Therefore, finding a material that can both adhere to the organ to facilitate transplantation and monitor and repair the organ is of paramount importance. [Summary of the Invention]

[0005] To address the issue of high modulus in existing piezoelectric materials hindering proper adhesion during organ transplantation, this invention provides a medical repair material, its preparation method, and a medical transplant bag.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for preparing a medical repair material, comprising the following steps:

[0007] We offer piezoelectric elastomers and polylactic acid fibers;

[0008] A dichloromethane solution and an N,N-dimethylformamide solution are provided, and the solution obtained by mixing dichloromethane and N,N-dimethylformamide is used as the first solution;

[0009] A dichloromethane solution is provided, with dichloromethane used as a second solution;

[0010] The piezoelectric elastomer is dissolved in a first solution and electrospinned to form a piezoelectric fiber film, and the polylactic acid fiber is dissolved in a second solution and electrospinned to form a fiber skeleton.

[0011] After attaching a piezoelectric fiber film to a fiber skeleton, the material is then subjected to drying and annealing processes to obtain a medical repair material.

[0012] Preferably, the elastic modulus of the medical repair material is 0.1-3 MPa.

[0013] Preferably, providing a piezoelectric elastomer includes the following steps:

[0014] Butylene glycol, lactic acid, sebacic acid and itaconic acid are provided as raw materials;

[0015] The raw materials are mixed and reacted to obtain a preformed elastomer;

[0016] After dissolving the pre-prepared elastomer with chlorinated hydrocarbons, the piezoelectric elastomer is obtained by sequential precipitation and drying.

[0017] Preferably, the molar ratio of hydroxyl to carboxyl groups in the preformed elastomer is (1.5~1):1, and the molar ratio of itaconic acid to carboxyl groups in the preformed elastomer is 1:(8~12).

[0018] Preferably, the mixing and reaction of the raw materials specifically includes:

[0019] After mixing the raw materials, react them at a first temperature for a first time, then raise the temperature to a second temperature and react for a second time.

[0020] After reacting at the second temperature for a second time, the temperature is lowered to the third temperature. After cooling, a catalyst is added and the reaction is carried out for a third time to obtain the preformed elastomer.

[0021] Among them, the second temperature > the first temperature > the third temperature.

[0022] Preferably, the piezoelectric elastomer obtained after sequential precipitation and drying processes specifically includes:

[0023] After the pre-prepared elastomer is dissolved, excess cold methanol is added to the solution, followed by standing and filtration to obtain a precipitated sample. The precipitated sample is then dried at 50-60 °C to obtain a piezoelectric elastomer.

[0024] Preferably, attaching the piezoelectric fiber film to the fiber skeleton specifically includes:

[0025] Provide a first syringe, a second syringe, and a collector;

[0026] The piezoelectric elastomer is dissolved in the first solution and then added to the first syringe;

[0027] After dissolving polylactic acid fibers in the second solution, add the solution into the second syringe;

[0028] The first and second syringes simultaneously perform electrospinning under a voltage of 10~12kV, and the discharged piezoelectric fiber film is attached to the surface of the discharged fiber skeleton in the collector.

[0029] Both the piezoelectric fiber film and the fiber skeleton have a mesh structure.

[0030] Preferably, the medical repair material is obtained by sequentially performing drying and annealing treatments, including:

[0031] The fiber skeleton with the piezoelectric fiber film attached is dried as a pre-product and then annealed at 130℃~140℃ for 50~60 minutes. The annealed pre-product is cooled to room temperature to obtain medical repair material.

[0032] To solve the above-mentioned technical problems, the present invention provides another technical solution as follows: a medical repair material, prepared by the above-mentioned method for preparing medical repair materials.

[0033] To solve the above-mentioned technical problems, the present invention provides another technical solution as follows: a medical transplant bag, comprising a body and at least two connecting wires, wherein the body is provided with a signal input port and a signal output port, and the connecting wires are used to connect the signal input port to an external monitoring device and the signal output port to an external monitoring device, and the material of the body is the aforementioned medical repair material.

[0034] Compared with the prior art, the medical repair material, preparation method, and medical transplant bag provided by the present invention have the following beneficial effects:

[0035] 1. A method for preparing a medical repair material provided in this embodiment of the invention includes the following steps:

[0036] We offer piezoelectric elastomers and polylactic acid fibers;

[0037] A dichloromethane solution and an N,N-dimethylformamide solution are provided, and the solution obtained by mixing dichloromethane and N,N-dimethylformamide is used as the first solution;

[0038] A dichloromethane solution is provided, with dichloromethane used as a second solution;

[0039] The piezoelectric elastomer is dissolved in a first solution and electrospinned to form a piezoelectric fiber film, and the polylactic acid fiber is dissolved in a second solution and electrospinned to form a fiber skeleton.

[0040] After attaching a piezoelectric fiber film to a fiber skeleton, the material is then subjected to drying and annealing processes to obtain a medical repair material.

[0041] Medical repair materials can provide effective in-situ electrical stimulation to the surface of the organ to be transplanted, allowing the stimulated organ to repair itself. Furthermore, the piezoelectric fiber film provides a low elastic modulus, enabling the medical repair material to adhere well to the surface of the organ to be transplanted. The medical repair material prepared in this embodiment also has a monitoring function. Simply connect it to an external monitoring device; when applied to the surface of the organ to be transplanted, it can continuously receive physiological state information from the organ during the generation of piezoelectric signals and transmit this information to the external monitoring device.

[0042] 2. The elastic modulus of the medical repair material described in this embodiment of the invention is 0.1-3 MPa. The elastic modulus of the medical repair material in this embodiment is lower than that of existing piezoelectric materials, resulting in better flexibility and tensile properties, making it easier to adhere to the surface of the organ to be transplanted. Furthermore, the piezoelectric elastomer prepared from the above material, together with the provided polylactic acid fiber, produces a medical repair material with good biodegradability and biocompatibility.

[0043] 3. The piezoelectric elastomer provided in this embodiment of the invention includes the following steps:

[0044] Butylene glycol, lactic acid, sebacic acid and itaconic acid are provided as raw materials;

[0045] The raw materials are mixed and reacted to obtain a preformed elastomer;

[0046] After dissolving the pre-prepared elastomer with chlorinated hydrocarbons, the piezoelectric elastomer is obtained by sequential precipitation and drying.

[0047] The co-participation of lactic acid and itaconic acid in the copolymerization reaction enhances the piezoelectric effect of the piezoelectric elastomer. In this example, sebacic acid and butanediol provide long, straight carbon chains, i.e., a long, flexible segment, which helps lower the glass transition temperature of the product, thereby reducing the elastic modulus of the piezoelectric elastomer. The C=C double bonds in itaconic acid provide curing crosslinking sites for the piezoelectric elastomer during copolymerization. During subsequent heat treatment, these curing crosslinking sites allow the piezoelectric elastomer to form a network structure, which further reduces the modulus.

[0048] 4. In this embodiment of the invention, the molar ratio of hydroxyl to carboxyl groups in the pre-formed elastomer is (1.5~1):1, and the molar ratio of itaconic acid to carboxyl groups in the pre-formed elastomer is 1:(8~12). This embodiment, by selectively setting the molar ratio of hydroxyl to carboxyl groups, and the molar ratio of itaconic acid to carboxyl groups, enables the prepared piezoelectric elastomer to possess both a low elastic modulus and superior piezoelectric properties. This solves the problem in the prior art where mixing flexible and piezoelectric materials results in a trade-off between piezoelectric properties and flexibility.

[0049] 5. In this embodiment of the invention, the mixing and reaction of raw materials specifically includes:

[0050] After mixing the raw materials, react them at a first temperature for a first time, then raise the temperature to a second temperature and react for a second time.

[0051] After reacting at the second temperature for a second time, the temperature is lowered to the third temperature. After cooling, a catalyst is added and the reaction is carried out for a third time to obtain the preformed elastomer.

[0052] The order of temperature is: second temperature > first temperature > third temperature. By selectively controlling the temperature, a preformed elastomer with a lower modulus can be obtained.

[0053] 6. The piezoelectric elastomer obtained after sequential precipitation and drying treatments in the embodiments of the present invention specifically includes:

[0054] After adding excess cold methanol to the solution of the pre-prepared elastomer, the solution is allowed to stand and then filtered to obtain a precipitated sample. The precipitated sample is then dried at 50-60 °C to obtain the piezoelectric elastomer. The operation is simple.

[0055] 7. In this embodiment of the invention, attaching the piezoelectric fiber film to the fiber skeleton specifically includes:

[0056] Provide a first syringe, a second syringe, and a collector;

[0057] The piezoelectric elastomer is dissolved in the first solution and then added to the first syringe;

[0058] After dissolving polylactic acid fibers in the second solution, add the solution into the second syringe;

[0059] The first and second syringes simultaneously perform electrospinning under a voltage of 10~12kV, and the discharged piezoelectric fiber film is attached to the surface of the discharged fiber skeleton in the collector.

[0060] Both the piezoelectric fiber film and the fiber skeleton have a mesh structure.

[0061] Polylactic acid (PLA) fibers form the scaffold structure, providing a certain level of support strength. Piezoelectric fiber films offer piezoelectric properties and a low elastic modulus. This results in a medical repair material with excellent bending and tensile properties, addressing the issues of insufficient flexibility and poor kidney adhesion in existing implants.

[0062] 8. In this embodiment of the invention, drying and annealing processes are performed sequentially to obtain medical repair materials, including:

[0063] A fiber skeleton with an attached piezoelectric fiber film is dried as a pre-product and then annealed at 130℃~140℃ for 50~60 minutes. The annealed pre-product is then cooled to room temperature to obtain a medical repair material. The resulting medical repair material is simple and convenient to operate, and exhibits good bending and tensile properties.

[0064] 9. This invention also provides a medical repair material, which has the same beneficial effects as the preparation method of the above-mentioned medical repair material, and will not be described in detail here.

[0065] 10. This invention also provides a medical transplant bag, which has the same beneficial effects as the above-mentioned preparation method of a medical repair material, and will not be described in detail here. [Attached Image Description]

[0066] Figure 1 This is a schematic diagram of the preparation method of the medical repair material provided in the first embodiment of the present invention.

[0067] Figure 2 This is a schematic diagram of the structure of the piezoelectric fiber film and fiber skeleton of the medical repair material provided in the first embodiment of the present invention.

[0068] Figure 3a This is a schematic diagram illustrating the effect of the mass ratio of polylactic acid fiber and piezoelectric elastomer co-spun on the piezoelectric properties of the final medical repair material in this invention.

[0069] Figure 3b This is a schematic diagram illustrating the therapeutic effect of the medical repair material provided by this invention in the field of kidney transplantation.

[0070] Figure 4a This is a schematic diagram illustrating the therapeutic effect of the medical repair material provided by this invention in the field of ureteral repair. Figure 1 .

[0071] Figure 4b This is a schematic diagram illustrating the therapeutic effect of the medical repair material provided by this invention in the field of ureteral repair. Figure 2 .

[0072] Figure 4c This is a schematic diagram (3) illustrating the therapeutic effect of the medical repair material provided by this invention applied in the field of ureter repair.

[0073] Figure 5 This is a schematic diagram of the structure of a medical transplant bag provided in the third embodiment of the present invention.

[0074] Explanation of reference numerals in the attached diagram:

[0075] 1. Medical transplant bag;

[0076] 11. Main body; 12. Connecting cable; 13. Signal input port; 14. Signal output port.

Detailed Implementation Methods

[0077] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0078] In the embodiments provided by this invention, it should be understood that "B corresponding to A" means that B is associated with A, and B can be determined based on A. However, it should also be understood that determining B based on A does not mean determining B solely based on A; B can also be determined based on A and / or other information.

[0079] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the invention. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Those skilled in the art should also recognize that the embodiments described in the specification are optional embodiments, and the actions and modules involved are not necessarily essential to the invention.

[0080] In various embodiments of the present invention, it should be understood that the sequence number of each process does not necessarily imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0081] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, or they may sometimes be executed in reverse order, depending on the functions involved. It is particularly important to note that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0082] Piezoelectric materials have been found to accelerate the healing of wounds, muscle and tendon defects through effective in-situ electrical stimulation. Therefore, they are widely used in the medical field as biomedical materials.

[0083] Current organ transplantation techniques typically involve applying electrical stimulation to the nerve tissue within the organ to promote organ function recovery. Piezoelectric materials can be used to fabricate monitors that continuously monitor the organ's physiological parameters during transplantation, helping doctors monitor the transplanted organ's condition in real time. Furthermore, these monitors can also release electrical signals to stimulate the organ's nerves, further promoting organ function recovery.

[0084] The high elastic modulus of existing piezoelectric materials limits their use in organ transplantation to simply monitoring and providing electrical signals; they cannot effectively adhere to the organ to aid in the transplant process. Therefore, finding a material that can both adhere to the organ to facilitate transplantation and monitor and repair the organ is of paramount importance.

[0085] Please see Figure 1 The first embodiment of the present invention provides a method for preparing a medical repair material, comprising the following steps:

[0086] S1 provides piezoelectric elastomers and polylactic acid fibers;

[0087] S2 provides a dichloromethane solution and an N,N-dimethylformamide solution, wherein the solution obtained by mixing dichloromethane and N,N-dimethylformamide is used as the first solution;

[0088] S3 provides a dichloromethane solution, using dichloromethane as the second solution;

[0089] S4, dissolve the piezoelectric elastomer in the first solution and perform electrospinning to form a piezoelectric fiber film, and dissolve the polylactic acid fiber in the second solution and perform electrospinning to form a fiber skeleton;

[0090] S5 involves attaching a piezoelectric fiber film to a fiber skeleton and then sequentially performing drying and annealing treatments to obtain a medical repair material.

[0091] Understandably, traditional medical monitors are typically thin-film devices. Firstly, during organ transplantation, the surface of the human organ is not flat, making it difficult for the monitor to adhere easily. Secondly, monitors made from existing piezoelectric materials have a low elastic modulus, meaning the monitor itself has a certain strength; forcibly adhering it to the organ surface could damage the organ to be transplanted. Therefore, it is crucial to find a medical repair material with a low elastic modulus, enabling it to conform well to human organs in the biomedical field, such as skin surfaces, wounds, muscles, damaged tendons, ureters, urethra, bladder, or the surface of the organ to be transplanted.

[0092] In this embodiment, a piezoelectric elastomer and polylactic acid fiber are first provided. It should be understood that the piezoelectric elastomer itself has a low elastic modulus, resulting in medical repair materials prepared from this material also possessing a low elastic modulus. This allows for good bending and tensile properties in the biomedical field, addressing the problems of insufficient flexibility and poor adhesion to the transplanted organ in existing implants or monitors. The polylactic acid fiber forms the scaffold structure, providing a certain level of support strength.

[0093] Specifically, in this embodiment, a dichloromethane solution and an N,N-dimethylformamide solution are provided. The solution obtained by mixing dichloromethane and N,N-dimethylformamide is used as the first solution, and the piezoelectric elastomer is dissolved in the first solution and electrospun to form a piezoelectric fiber film. It should be understood that the piezoelectric fiber film formed by electrospinning has a mesh structure. Further, a dichloromethane solution is provided as the second solution; polylactic acid fibers are dissolved in the second solution and electrospun to form a fiber skeleton. The fiber skeleton formed by electrospinning has a mesh structure. Further, the piezoelectric fiber film with a mesh structure is attached to the fiber skeleton and then subjected to drying and annealing treatments to obtain a medical repair material. The piezoelectric fiber film can effectively cover the polylactic acid fiber skeleton and provide nodes at the fiber skeleton joints, converting weak mechanical vibrations into global vibrations of the fiber film. Furthermore, the piezoelectric fiber film possesses piezoelectric properties. Therefore, during vibration, the medical repair material prepared from the piezoelectric fiber film can provide effective in-situ electrical stimulation to the surface of the organ to be transplanted, and the stimulated organ can repair itself. Further, the piezoelectric fiber film provides a low elastic modulus, allowing the medical repair material to adhere well to the surface of the organ to be transplanted. Moreover, the medical repair material prepared in this embodiment also has a monitoring function. Simply connect it to an external monitoring device; when the medical repair material is applied to the surface of the organ to be transplanted, it can continuously receive physiological state information of the organ during the generation of piezoelectric signals and transmit this information to the external monitoring device.

[0094] For example, renal ischemia-reperfusion injury is an unavoidable kidney damage process during kidney transplantation, severely impairing the quality of the transplanted kidney and causing adverse clinical reactions such as delayed recovery of transplanted kidney function and rejection. However, there are currently no effective treatments for renal ischemia-reperfusion injury in clinical practice. Specifically, the medical repair material prepared by the method provided in this embodiment can be applied in the field of kidney transplantation. The piezoelectric fiber film in the medical repair material can effectively cover the polylactic acid fiber skeleton and provide nodes at the fiber skeleton junction, converting weak mechanical vibration into global vibration of the fiber film. This can achieve local, in-situ, real-time weak electrical stimulation in the kidney, promoting renal tubular repair in renal ischemia-reperfusion injury. On the other hand, the medical repair material has good bending and tensile properties, which can solve the problems of insufficient flexibility and poor adhesion to the kidney of existing implants.

[0095] Specifically, the elastic modulus of the medical repair material is 0.1-3 MPa. Understandably, the elastic modulus of the medical repair material in this embodiment is lower than that of existing piezoelectric materials, resulting in better flexibility and tensile properties, making it easier to adhere to the surface of the organ to be transplanted. Furthermore, the piezoelectric elastomer prepared from the above material, together with the provided polylactic acid fiber, forms a medical repair material with good biodegradability and biocompatibility. When it coats the organ surface, it causes no harmful irritation to the organ; or when applied to the repair of wounds, muscles, or damaged tendons, it causes no harmful irritation to the recipient after implantation and can completely degrade within a certain time, eliminating the need for removal.

[0096] Furthermore, providing a piezoelectric elastomer includes the following steps:

[0097] S11 provides butanediol, lactic acid, sebacic acid and itaconic acid as raw materials;

[0098] S12, the raw materials are mixed and reacted to obtain a preformed elastomer;

[0099] S13 is obtained by dissolving a pre-prepared elastomer with chlorinated hydrocarbons, followed by precipitation and drying processes.

[0100] Understandably, the piezoelectric elastomer in this embodiment is prepared by copolymerization of butanediol (BDO), lactic acid (LA), sebacic acid (SA), and itaconic acid (IA). Lactic acid and itaconic acid can provide C=O double bonds to enhance the piezoelectric properties of the elastomer. Furthermore, the co-participation of lactic acid and itaconic acid in the copolymerization reaction further enhances the piezoelectric effect. If lactic acid is directly polymerized to form polylactic acid, although it has good piezoelectric properties, its high modulus prevents the final product from adhering well to organ transplant surfaces. In this example, sebacic acid and butanediol provide long, straight carbon chains, i.e., a long, flexible segment, which helps lower the glass transition temperature of the product, thereby reducing the elastic modulus of the piezoelectric elastomer. This allows the piezoelectric elastomer to possess better deformation capacity, enabling it to deform in response to external forces. The C=C double bonds in itaconic acid provide curing crosslinking sites for the piezoelectric elastomer during copolymerization. During the subsequent electrospinning process, the solidification of crosslinking sites allows the piezoelectric fiber film to form a network structure, which further reduces the modulus of the piezoelectric fiber film.

[0101] Therefore, the piezoelectric elastomer prepared from this raw material has a low elastic modulus. Consequently, medical repair materials made from this piezoelectric elastomer are easier to apply to the surface of organs to be transplanted.

[0102] Specifically, the molar ratio of hydroxyl to carboxyl groups in the preformed elastomer is (1.5~1):1, and the molar ratio of itaconic acid to carboxyl groups in the preformed elastomer is 1:(8~12).

[0103] Preferably, the molar ratio of hydroxyl to carboxyl groups in the preformed elastomer is 1.1:1. The hydroxyl groups are mainly provided by alcohols, such as the hydroxyl groups on butanediol and lactic acid. The carboxyl groups are mainly provided by acids, such as lactic acid, sebacic acid, and itaconic acid. Since alcohols have slightly lower boiling points than acids, they are more likely to produce vaporization products during high-temperature reactions, leading to an imbalance in the alcohol-acid ratio. Therefore, in this embodiment, a higher proportion of alcohols is selectively designed to avoid this imbalance during the preparation of the piezoelectric elastomer.

[0104] Preferably, the molar ratio of itaconic acid to carboxyl groups in the preformed elastomer is 1:10. The C=C double bonds in itaconic acid provide curing and crosslinking sites for the piezoelectric elastomer during copolymerization. These curing and crosslinking sites help the piezoelectric fiber film form a network structure, further reducing its modulus. If the amount of itaconic acid is too low, the provided C=C double bonds cannot provide sufficient curing and crosslinking sites, resulting in the inability to form a network structure. If the amount of itaconic acid is too high, thermal oxidation occurs at high temperatures, causing premature crosslinking. This means the resulting piezoelectric elastomer is already crosslinked before electrospinning, preventing the formation of a network structure piezoelectric fiber film during electrospinning, thus making it unsuitable for manufacturing medical repair materials.

[0105] It should be understood that traditional piezoelectric materials typically employ a mixture of flexible and piezoelectric materials to achieve lower flexibility. However, flexible materials themselves do not possess piezoelectric properties; therefore, directly mixing the two materials will reduce the piezoelectric performance of the piezoelectric material. Thus, traditional mixing methods suffer from the incompatibility of achieving both piezoelectric properties and flexibility. In this embodiment, by selectively choosing reactive monomers, lactic acid and itaconic acid provide C=O double bonds to enhance the piezoelectric properties of the piezoelectric elastomer. Sebacic acid and butanediol provide long, straight carbon chains to reduce the elastic modulus, and the C=C double bonds in itaconic acid provide curing and crosslinking sites for the piezoelectric elastomer during copolymerization. This results in a network structure in the final piezoelectric fiber film, further reducing the elastic modulus. Finally, in the preparation of medical repair materials, the piezoelectric elastomer is electrospun into a network structure piezoelectric fiber film. Compared to traditional dense films, electrospinning itself results in a fibrous structure, while the crosslinked network structure of the piezoelectric fiber film exhibits a lower elastic modulus and better adhesion. Therefore, the medical repair material prepared in this embodiment can better adhere to the organ to be transplanted.

[0106] It should be noted that this embodiment, by selectively setting the molar ratio of hydroxyl and carboxyl groups, as well as the molar ratio of itaconic acid and carboxyl groups, enables the prepared piezoelectric elastomer to possess both a low elastic modulus and superior piezoelectric properties. This solves the problem in the prior art where mixing flexible and piezoelectric materials results in a trade-off between the piezoelectric properties and flexibility of the piezoelectric material.

[0107] Specifically, the mixing and reaction of raw materials includes:

[0108] S121: After mixing the raw materials, react them at a first temperature for a first time, then raise the temperature to a second temperature and react for a second time.

[0109] S122, after reacting at the second temperature for a second time, is cooled to the third temperature. After cooling is complete, a catalyst is added and reacted for a third time to obtain a pre-made elastomer.

[0110] Among them, the second temperature > the first temperature > the third temperature.

[0111] It should be understood that the control of reaction conditions is extremely important in the copolymerization of butanediol, lactic acid, sebacic acid, and itaconic acid to prepare piezoelectric elastomers. Specifically, after mixing the raw materials under a nitrogen atmosphere, the mixture is reacted at a first temperature for a first time, followed by a heating treatment to a second temperature for a second time. The first temperature is 125℃~130℃, and the first time is 40 min~1 h. After the heating treatment, the second temperature is 175℃~180℃, and the second time is 1.8 min~2 h. It should be understood that after mixing the raw materials, the monomers in the raw materials will undergo homopolymerization, resulting in poor copolymerization. After heating, the monomers undergoing homopolymerization can decompose back into monomeric states, preventing the homopolymerization reaction from occurring. Further, after reacting at the second temperature for a second time, the temperature is lowered to a third temperature. After cooling, a catalyst is added, and the reaction is carried out for a third time to obtain the pre-formed elastomer. The third temperature is 100℃~105℃, and the third time is 7.5~8 h. Cooling can adapt to the reaction temperature of the catalyst, thus accelerating the copolymerization reaction. The catalyst can be 0.1% tetrabutyl titanate (TBT) and 0.1% polymerization inhibitor. Preferably, after cooling, during the addition of the catalyst and continued reaction, the pressure of the reaction environment can be reduced to a vacuum environment (300 Pa) for 8 hours. Furthermore, the temperature can be appropriately increased during the reaction to accelerate the reaction rate, thereby ensuring the copolymerization of the raw materials is completed as quickly as possible to prepare the preformed elastomer.

[0112] Further, in step S13 above, obtaining the piezoelectric elastomer after sequential precipitation and drying processes specifically includes:

[0113] After dissolving the pre-prepared elastomer, excess cold methanol is added to the solution, followed by standing and filtration to obtain a precipitate. The precipitate is then dried at 50–60 °C to obtain the piezoelectric elastomer. Understandably, after preparing the pre-prepared elastomer, the solution containing the pre-prepared elastomer can be dissolved in a chlorinated hydrocarbon solution, such as dichloromethane or trichloromethane. This solution allows for complete dissolution of the pre-prepared elastomer, facilitating the removal of unpolymerized monomers and oligomers. Further, after dissolution, excess cold methanol is added to the solution, and the solution is allowed to stand and precipitate. After precipitation, filtration yields the precipitate. The precipitate is then dried at 50–60 °C to obtain the uncrosslinked piezoelectric elastomer; the operation is simple.

[0114] Specifically, in step S5 above, attaching the piezoelectric fiber film to the fiber skeleton includes:

[0115] S51, providing a first syringe, providing a second syringe, and a collector;

[0116] S52, after dissolving the piezoelectric elastomer in the first solution, add it into the first syringe;

[0117] S53, after dissolving polylactic acid fibers in the second solution, add them into the second syringe;

[0118] S54, the first syringe and the second syringe simultaneously perform electrospinning under a voltage of 10~12kV, and the discharged piezoelectric fiber film is attached to the surface of the discharged fiber skeleton in the collector.

[0119] Both the piezoelectric fiber film and the fiber skeleton have a mesh structure.

[0120] Specifically, both the first and second syringes consist of a roller, a piston, and a needle tip. The needle tip is located at one end of the roller, and the piston is located at the other end. The roller is used to hold liquid, and its inner wall is provided with a channel that connects to the needle tip. The piston can move inside the roller to push the liquid through the channel and out of the needle tip.

[0121] For example, 0.6 g of piezoelectric elastomer is dissolved in 6 mL of dichloromethane (DSC), and the dichloromethane is stirred at room temperature for 12 h to obtain a homogeneous solution. The homogeneous solution is transferred to a 10 mL second syringe, with the needle tip connected to a high-voltage power supply and the roller grounded. The flow rate of the solution in the second syringe is set to 1 mL / h, the distance between the syringe needle and the collector is set to 15 cm, and the voltage value is set to 11.5 kV. The piston is pushed to start spinning and discharge the fiber skeleton. Further, 0.6 g of piezoelectric elastomer is dissolved in a 6 mL mixed solution of dichloromethane (DSC) and N,N-dimethylformamide (DMF), and the mixed solution is stirred at room temperature for 12 h to obtain a homogeneous solution. The homogeneous solution is transferred to a 10 mL first syringe, with the needle tip connected to a high-voltage power supply and the roller grounded. The flow rate of the solution in the first syringe is set to 1 mL / h, the distance between the syringe needle and the collector is set to 15 cm, and the voltage value is set to 11.5 kV. The piston is pushed to start spinning and discharge the piezoelectric fiber film, causing the discharged piezoelectric fiber film to adhere to the surface of the fiber skeleton.

[0122] Please participate as well. Figure 2 , Figure 2 The coarser mesh fibers form the fibrous skeleton, while the finer mesh fibers form the piezoelectric fiber film. The fibrous skeleton and piezoelectric fiber film give the medical repair material prepared from it a low elastic modulus and good tensile strength.

[0123] It should be noted that the electrospinning process described above can be performed simultaneously with the first and second syringes, or the first syringe can be used for electrospinning first, followed by the second syringe. Alternatively, the second syringe can be used for electrospinning first, followed by the first syringe. The key is that the final result is a piezoelectric fiber film attached to the surface of the fiber skeleton. The specific process is not limited.

[0124] Understandably, the collector is used to collect the fibrous skeleton and piezoelectric fiber membrane, both of which are woven fibrous structures. The resulting piezoelectric fiber membrane and fibrous skeleton are both woven fibrous structures. The piezoelectric fiber membrane is attached to the surface of the fibrous skeleton, with polylactic acid fibers forming the skeleton structure, providing a certain degree of support strength. The piezoelectric fiber membrane provides piezoelectric properties and a low elastic modulus. This results in a medical repair material with excellent bending and tensile properties, addressing the problems of insufficient flexibility and poor adhesion to the kidney in existing implants.

[0125] Specifically, in this embodiment, the mass ratio of polylactic acid fiber and piezoelectric elastomer co-spun yarn ranges from (1:1) to (2:1). The preferred mass ratio of polylactic acid fiber and piezoelectric elastomer co-spun yarn is 2:1. Please refer to... Figure 3a , Figure 3a This study demonstrates the effect of the mass ratio of polylactic acid (PLA) fiber to piezoelectric elastomer co-spun yarn on the piezoelectric properties of the final medical repair material. For example, when the PLA fiber:piezoelectric elastomer (P:L) ratio is 1:0 (i.e., no piezoelectric elastomer is added), the generated voltage of the medical repair material is 6.6 mV. When the PLA fiber:piezoelectric elastomer (P:L) ratio is 2:1, the generated voltage is 16.6 mV. When the PLA fiber:piezoelectric elastomer (P:L) ratio is 1:1, the generated voltage is 7.9 mV. When the PLA fiber:piezoelectric elastomer (P:L) ratio is 1:2 (i.e., no piezoelectric elastomer is added), the generated voltage is 12.8 mV. Therefore, by appropriately setting the mass ratio of PLA fiber and piezoelectric elastomer co-spun yarn, the final medical repair material exhibits excellent piezoelectric properties.

[0126] Further, in step S5 above, drying and annealing are performed sequentially to obtain the medical repair material, including:

[0127] The fiber skeleton with the piezoelectric fiber film attached is dried as a pre-product and then annealed at 130℃~140℃ for 50~60 minutes. The annealed pre-product is cooled to room temperature to obtain medical repair material.

[0128] For example, after electrospinning, the fiber skeleton with the piezoelectric fiber film attached can be taken out from the collector as a pre-product. After drying the pre-product, it is annealed at 140°C for 60 minutes and then cooled to room temperature to obtain the medical repair material. The operation is simple and convenient, and the formed medical repair material has good bending and tensile properties.

[0129] To address the aforementioned technical problems, the second embodiment of the present invention also provides a medical repair material, which is prepared using the medical repair material preparation method described above.

[0130] It should be understood that the medical repair material provided in this embodiment has a low elastic modulus, which makes it suitable for use in the biomedical field. It exhibits good bending and tensile properties, addressing the problems of insufficient flexibility and poor adhesion to the transplanted organ in existing implants or monitors. For example, it can be applied in the field of kidney transplantation to promote renal tubular repair in renal ischemia-reperfusion injury. Furthermore, it can also be used in the medical field to accelerate the healing of wounds, muscle and tendon defects, demonstrating its wide range of applications.

[0131] Please see Figure 3b , Figure 3b This diagram illustrates the therapeutic effects of medical repair materials applied in kidney transplantation. Sham represents the control group, IRI represents defect-reperfusion injury (kidney injury), and IRI+ES represents the recovery effect after injury using the medical repair materials. H&E and PaS represent two different staining methods. More blank areas indicate more glomerular and tubular necrosis. It is evident that on day one, the kidneys using the medical repair materials suffered severe damage. On day two, the kidneys not using the materials began to show damage, while the kidneys using the materials began to repair. By day seven, the kidneys not using the materials suffered severe damage, while the kidneys using the materials were essentially repaired. Therefore, the medical repair materials provided in this embodiment can restore the function of transplanted organs, such as the kidneys.

[0132] Please see Figure 4a , Figure 4aThis is a schematic diagram illustrating the therapeutic effect of medical repair materials applied in ureteral repair. The vertical axis of the three line graphs represents the amount of radionuclides accumulated in the kidneys, while the horizontal axis represents time. The control group shows the radionuclide accumulation in both kidneys under normal conditions. It can be seen that under normal conditions, both kidneys maintain a high level of radionuclide accumulation, with a slight decreasing trend over time. In the ureteral stenosis group, it is clearly evident that the ureteral stenosis leads to a lower amount of radionuclide accumulation in the left kidney. When the medical repair material is applied to the ureteral stenosis, the electrical stimulation provided by the material increases the amount of radionuclide accumulation in the left kidney, alleviating the ureteral stenosis. The bar graph represents the glomerular filtration rate (GFR) level when the medical repair material is applied to ureteral repair. "Sham" represents the blank group, indicating the GFR of patients in a healthy state. "US" represents the ureteral stenosis group, and "US+ES" represents the group treated with the medical repair material in the ureteral stenosis group. It is evident that the glomerular filtration rate significantly increased under the influence of medical repair materials. Furthermore, a statistically significant difference was clearly observed between the data from those who did not use medical repair materials and those who did.

[0133] Please refer to the following: Figure 4b , Figure 4b This diagram illustrates the therapeutic effect of medical repair materials in ureteral repair. The blank group represents the thickness of ureteral epithelial cells in healthy patients. US represents the ureteral stricture group, and US+ES represents the group treated with medical repair materials in ureteral stricture. It is evident that the thickness of ureteral epithelial cells is significantly reduced under the influence of the medical repair materials. Furthermore, there is no statistically significant difference in the thickness of ureteral epithelial cells between the blank group and the group treated with medical repair materials. However, there are significant statistically significant differences between the blank group and the group treated with medical repair materials and the group not treated with medical repair materials. It should be noted that "no statistical difference" means that the difference between the two groups did not reach a statistically significant level; that is, the difference lacks sufficient evidence to support the proposed hypothesis and may be due to sampling error rather than research factors. This does not mean that the two groups are completely identical, but rather that the difference did not reach a statistically significant level.

[0134] Please combine them together Figure 4c , Figure 4cThis diagram illustrates the therapeutic effects of medical repair materials applied to ureteral repair. The blank group represents the amount of collagen deposition in patients in a healthy state. US represents the amount of collagen deposition in the ureteral stricture group, and US+ES represents the amount of collagen deposition in the ureteral stricture group after the application of medical repair materials. It is evident that the thickness of collagen deposition is significantly reduced under the influence of the medical repair materials. Furthermore, there is no statistically significant difference in collagen deposition between the blank group and the group using medical repair materials, but there are significant statistically significant differences between the blank group and the group using medical repair materials and the group not using medical repair materials. It should be understood that after the application of medical repair materials to ureteral stricture, the thickness of ureteral epithelial cells is significantly reduced, indicating that the patient's ureter is less obstructed and the degree of fibrosis is milder. In addition, the significant reduction in collagen deposition thickness also indicates a reduction in the degree of fibrosis in the ureter, which is beneficial for the repair of ureteral trauma.

[0135] It should be noted that the medical repair material provided in this embodiment can be applied to skin wound repair, muscle repair, repair of damaged tendons, ureter repair, urethral repair, bladder repair, or repair of organs awaiting transplantation. Its application range is wide. Furthermore, it can fill the gap in the existing medical field where there are no corresponding methods for repairing human organs, such as ureters, urethral repair, bladder, or kidneys awaiting transplantation.

[0136] The medical repair material provided in this embodiment of the invention has the same beneficial effects as the preparation method of the aforementioned medical repair material, and will not be described in detail here.

[0137] To solve the above-mentioned technical problems, the third embodiment of the present invention also provides a medical transplant bag 1, including a body 11 and at least two connecting lines 12. The body 11 is provided with a signal input port 13 and a signal output port 14. The connecting lines 12 are used to connect the signal input port 13 to an external monitoring device and the signal output port 14 to an external monitoring device. The material of the body 11 is the aforementioned medical repair material.

[0138] Understandably, when the medical transplant bag 1 is applied to the surface of the organ to be transplanted, it can continuously receive physiological state information of the organ during the process of generating piezoelectric signals, and convert the physiological state information into electrical signals. The signal input port 13 and the signal output port 14 are electrically connected to the external monitoring device through the connecting line 12, and the signal output port 14 is connected to the external monitoring device. The electrical signal connecting line 12 transmits the signal to the external monitoring device so that the doctor can monitor the patient in real time.

[0139] The medical transplant bag 1 provided in this embodiment of the invention has the same beneficial effects as the preparation method of the above-mentioned medical repair material, and will not be described in detail here.

[0140] The foregoing has provided a detailed description of a medical repair material, its preparation method, and a medical transplant bag disclosed in the embodiments of the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention. Any modifications, equivalent substitutions, and improvements made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a medical repair material, characterized in that: Includes the following steps: Butylene glycol, lactic acid, sebacic acid and itaconic acid are provided as raw materials; The raw materials are mixed and reacted to obtain a preformed elastomer; After dissolving the pre-prepared elastomer with chlorinated hydrocarbons, the piezoelectric elastomer is obtained by sequential precipitation and drying. A dichloromethane solution and an N,N-dimethylformamide solution are provided, and the solution obtained by mixing dichloromethane and N,N-dimethylformamide is used as the first solution; A dichloromethane solution is provided, with dichloromethane used as a second solution; The piezoelectric elastomer is dissolved in a first solution and then added to the first syringe; the polylactic acid fiber is dissolved in a second solution and then added to the second syringe; the first syringe and the second syringe are simultaneously electrospun under a voltage of 10-12kV, so that the piezoelectric fiber film is discharged from the output end of the first syringe and the fiber skeleton is discharged from the output end of the second syringe, and the discharged piezoelectric fiber film is directly attached to the surface of the discharged fiber skeleton in the collector to form a composite network structure of piezoelectric fiber film and fiber skeleton. The mass ratio of polylactic acid fiber and piezoelectric elastomer co-spun is in the range of (1:1) to (2:1). After attaching a piezoelectric fiber film to a fiber skeleton, the material is then subjected to drying and annealing processes to obtain a medical repair material. The elastic modulus of the medical repair material is 0.1-3 MPa.

2. The method for preparing the medical repair material as described in claim 1, characterized in that: The molar ratio of hydroxyl to carboxyl groups in the preformed elastomer is (1.5~1):1, and the molar ratio of itaconic acid to carboxyl groups in the preformed elastomer is 1:(8~12).

3. The method for preparing the medical repair material as described in claim 1, characterized in that: The specific steps involved in mixing and reacting the raw materials are: After mixing the raw materials, react them at a first temperature for a first time, then raise the temperature to a second temperature and react for a second time. After reacting at the second temperature for a second time, the temperature is lowered to the third temperature. After cooling, a catalyst is added and the reaction is carried out for a third time to obtain the preformed elastomer. Among them, the second temperature > the first temperature > the third temperature.

4. The method for preparing a piezoelectric fiber thin film as described in claim 1, characterized in that: The piezoelectric elastomer obtained after sequential precipitation and drying processes specifically includes: After the pre-prepared elastomer is dissolved, excess cold methanol is added to the solution, followed by standing and filtration to obtain a precipitated sample. The precipitated sample is then dried at 50-60 °C to obtain a piezoelectric elastomer.

5. The method for preparing the medical repair material as described in claim 1, characterized in that: The medical repair material is obtained by sequentially drying and annealing processes, including: The fiber skeleton with the piezoelectric fiber film attached is dried as a pre-product and then annealed at 130℃~140℃ for 50~60 minutes. The annealed pre-product is cooled to room temperature to obtain medical repair material.

6. A medical repair material, characterized in that: It is prepared using the preparation method of medical repair material as described in any one of claims 1-5.

7. A medical transplant bag, characterized in that: The device includes a main body and at least two connecting wires. The main body is provided with a signal input port and a signal output port. The connecting wires are used to connect the signal input port to an external monitoring device and the signal output port to an external monitoring device. The main body is made of the medical repair material described in claim 6.

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