Collagen membrane substrate, double-sided hydrogel and preparation method and application thereof

Abstract

The application relates to a collagen membrane substrate, a double-sided hydrogel and a preparation method and application thereof, and relates to the technical field of biomedical materials. The collagen membrane substrate is prepared from a raw material composition comprising a Fe 3+ coordination system matched with morin and collagen; the double-sided self-growth hydrogel is obtained by coating a heat-responsive monomer solution and an antibacterial and antioxidant monomer solution on two sides of the substrate respectively, and initiating in-situ self-growth of the monomers by using the embedded coordination system in the substrate. The application can effectively solve the problems that the existing collagen membrane substrate lacks endogenous free radical initiation ability and it is difficult to grow different functional hydrogel layers on two sides of the same substrate, and a double-sided heterogeneous structure material with rapid heat response shrinkage, high-efficiency antibacterial and excellent antioxidant functions is obtained.

Description

Technical Field

[0001] This application relates to the field of biomedical materials technology, specifically to a collagen membrane substrate, a double-sided hydrogel, and its preparation method and application. Background Technology

[0002] Collagen, due to its excellent biocompatibility, biodegradability, and microstructure similar to the extracellular matrix, has broad application prospects in biomedical fields such as tissue engineering, wound repair, and drug sustained release. Currently, common strategies for preparing collagen-based composite hydrogels mainly include physical blending, chemical cross-linking, and layer-by-layer self-assembly. These methods typically use pre-formed synthetic or natural polymer hydrogels as carriers, loading collagen or collagen-containing materials onto the surface or interior of the carrier through physical adsorption or chemical grafting.

[0003] However, existing technologies have the following shortcomings: First, in physical blending or surface coating methods, the collagen component and the carrier mainly rely on non-covalent interactions such as hydrogen bonds and electrostatic interactions, resulting in weak binding forces. Under physiological conditions, these interactions are prone to detachment or degradation, leading to poor material structural stability and limited functional duration. Second, while conventional chemical cross-linking methods can improve the binding strength between collagen and the carrier, the cross-linking process often requires the introduction of additional cross-linking agents (such as glutaraldehyde and carbodiimide). These cross-linking agents may be cytotoxic, and the cross-linking reaction conditions are relatively harsh, easily disrupting the triple helix structure of collagen and affecting its biological activity. Third, existing collagen membrane substrates are mostly used as "inert carriers," lacking the ability to actively induce hydrogel formation in situ on the surface. The construction of the collagen layer requires an independent exogenous initiation system or complex multi-step reactions, making the preparation process cumbersome and difficult to achieve uniform and controllable growth of the collagen layer on both sides of the substrate.

[0004] Therefore, how to provide a collagen membrane substrate that can actively initiate the in-situ polymerization and growth of monomers on the surface without the addition of external crosslinking agents or additional initiation steps, and the double-sided self-growing collagen hydrogel prepared therefrom, has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] This application provides a collagen membrane substrate, a double-sided hydrogel, and its preparation method and application, in order to solve the technical problems of cumbersome preparation process and insufficient bonding strength of existing collagen membrane substrates.

[0006] To achieve the above objectives, this application provides the following technical solution: A first aspect of this application provides a collagen membrane substrate composed of Fe, including Fe2+ coordinated with fuzzycin. 3+ It is prepared by combining raw materials such as collagen.

[0007] The second aspect of this application provides a method for preparing a collagen membrane substrate according to any possible implementation of the first aspect, comprising the following steps: Mix lacryma-jobi with Fe 3+ The donor, in ionic form, is coordinated and complexed at pH 7.9–8.3, and then uniformly mixed with an acetic acid solution of collagen; the mixture is then molded and vacuum dried.

[0008] In an alternative embodiment, the Fe 3+ The donor is FeCl3·6H2O; the mass ratio of the laccoside to the FeCl3·6H2O is 10:27. The concentration of collagen in the acetic acid solution is 40 mg / mL. The drying conditions are: true temperature 40~60℃, duration 4~6h.

[0009] A third aspect of this application provides an application of the collagen membrane substrate described in any possible implementation of the first aspect in the field of biomedical materials.

[0010] The fourth aspect of this application provides a double-sided self-growing hydrogel, wherein a heat-responsive monomer solution and an antibacterial and antioxidant monomer solution are respectively coated on both sides of a substrate; wherein the substrate is a collagen membrane substrate as described in any possible implementation of the first aspect.

[0011] The fifth aspect of this application provides a method for preparing a double-sided self-growing hydrogel, wherein the preparation step of the thermally responsive monomer solution includes: dissolving the thermally responsive monomer, the first initiator and the first crosslinking agent in deionized water at a mass ratio of 120:5:5 to 130:15:15; The preparation steps of the antibacterial and antioxidant monomer solution include: dissolving the antibacterial monomer, antioxidant monomer, second initiator and second crosslinking agent in deionized water at a mass ratio of 200:200:15:15~210:220:25:25; and allowing it to grow for 5~10 minutes after uniform spraying.

[0012] In one optional embodiment, the thermally responsive monomer is N,N-diethylacrylamide; The antibacterial monomer is methacryloyloxyethyltrimethylammonium chloride; The antioxidant monomer is N-(3,4-dihydroxyphenylethyl)methacrylamide; Both the first and second initiators are ammonium persulfate. Both the first and second crosslinking agents are N,N'-methylenebisacrylamide.

[0013] In one optional embodiment, the mass ratio of the thermally responsive monomer, the first initiator, and the first crosslinking agent is 127:10:10; and the mass ratio of the antibacterial monomer, the antioxidant monomer, the second initiator, and the second crosslinking agent is 207:221:20:20.

[0014] The sixth aspect of this application provides an application of the double-sided self-growing hydrogel described in any possible implementation of the fourth aspect in the field of biomedical materials.

[0015] In one alternative embodiment, the double-sided self-growing hydrogel is used to prepare any one or more of biomedical dressings, soft actuators, or smart responsive materials.

[0016] This application provides a collagen membrane substrate, a double-sided hydrogel, its preparation method, and its application. This method utilizes lacquinone and Fe... 3+ Coordination complexes form stable complexes, which are then co-assembled with collagen to construct a three-dimensional network substrate based on Fe. 3+ The redox activity of the lacquer xanthophyll complex initiates the polymerization of double-bonded monomers under mild conditions. The catechol structure of lacquer xanthophyll is related to Fe... 3+ The strong coordination complexation significantly improved Fe 3+ Stability and dispersibility within the collagen microenvironment inhibited Fe 3+ The hydrolysis and precipitation of Fe improves the uniformity and transparency of the substrate structure. Simultaneously, the integration of this coordination system into the collagen fiber network enhances the mechanical strength of the substrate while retaining Fe. 3+ The redox activity provides endogenous initiation sites for subsequent bifacial self-growth, avoiding damage to the collagen structure caused by external light or heat. Furthermore, collagen provides a biocompatible and degradable framework, and the coordination structure endows the substrate with intrinsic antioxidant capacity, achieving an integrated design of an active substrate. This effectively solves the problems of existing collagen membrane substrates—namely, limited functionality, lack of metal-polyphenol synergistic stabilizing structure, and lack of integrated bioactivity—significantly enhancing the material's application potential in the biomedical field. Attached Figure Description

[0017] Figure 1 This is a macroscopic morphology diagram of the collagen membrane substrate prepared in this invention.

[0018] Figure 2 This is a cross-sectional scanning electron microscope image of the double-sided self-growing collagen hydrogel prepared according to the present invention.

[0019] Figure 3 This is a bar chart showing the thermal response shrinkage rate of double-sided hydrogels at different temperatures.

[0020] Figure 4The graph shows the test results of the antibacterial properties of the double-sided hydrogel against Escherichia coli and Staphylococcus aureus, as well as the statistical graph of the antibacterial rate.

[0021] Figure 5 The graph shows the test results of DPPH and ABTS removal rates for the double-sided hydrogel.

[0022] Figure 6 This is a graph showing the cell viability test results of a double-sided hydrogel.

[0023] Figure 7 This is a schematic diagram of the chemical structure of the double-sided self-growing collagen hydrogel thermal response layer [structural formula (1)] and the antibacterial and antioxidant layer [structural formula (2)]. Detailed Implementation

[0024] The present invention will now be described in further detail with reference to embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit the invention.

[0025] To achieve the above-mentioned objectives, this invention provides a collagen membrane substrate, a double-sided self-growing hydrogel, its preparation method, and its application. The overall technical solution is as described in the embodiments of this application, and mainly includes the following core technical elements: Fe coordinated with laccasein. 3+ The invention comprises an active substrate assembled with collagen, a double-sided self-growth polymerization process of thermally responsive monomers and antibacterial and antioxidant monomers, and a double-sided hydrogel material with an asymmetric functional structure constructed therefrom. These technical elements work together to constitute the overall technical solution of this invention.

[0026] In a first aspect, this embodiment provides a collagen membrane substrate. This collagen membrane substrate is composed of Fe, including lacquinone-coated Fe... 3+ The collagen raw material composition was prepared. In this embodiment, Fe was introduced into the collagen matrix by introducing rutin-coordinated Fe. 3+ The coordination system utilizes the catechol group of lacquinone with Fe 3+ The strong coordination and synergistic effect of hydrogen bonds construct a stable physical cross-linking network with endogenous free radical initiation activity, thereby solving the problems of poor structural stability and lack of subsequent functionalization initiation sites in traditional collagen hydrogels. Its beneficial effects are to endow the substrate with excellent mechanical strength, biocompatibility and as an endogenous initiation center for subsequent bifacial polymerization reactions.

[0027] Secondly, this embodiment provides a method for preparing a collagen membrane substrate. The method involves reacting flavonoids with Fe... 3+The donor, in ionic form, was coordinated and complexed at pH 7.9–8.3, and then uniformly mixed with an acetic acid solution of collagen; the mixture was then molded and vacuum dried. In this embodiment, pre-coordination and complexation under specific pH conditions ensured the Fe... 3+ The active complexed form is uniformly dispersed, avoiding its inactivation or precipitation during subsequent drying. At the same time, the use of an acetic acid solution system combined with vacuum drying process effectively maintains the triple helix structure of collagen and inhibits phase separation, thereby preparing a substrate sheet with a smooth surface, uniform thickness and good initiation activity.

[0028] As a specific implementation method, this embodiment provides preferred preparation parameters for a collagen membrane substrate. Fe 3+ The donor was FeCl3·6H2O; the mass ratio of lacquer xanthophyll to FeCl3·6H2O was 10:27; the concentration of collagen in the acetic acid solution was 40 mg / mL; the drying conditions were: temperature 40~60℃, time 4~6h. This embodiment uses FeCl3·6H2O as the iron source and performs vacuum drying at 40~60℃ for 4~6h, combined with a 10:27 ratio of lacquer xanthophyll to FeCl3·6H2O. 3+ The mass ratio and 2% collagen concentration allow for precise control of coordination stoichiometry and solvent evaporation rate, thereby solving the problems of poor process repeatability and high risk of protein denaturation. Its beneficial effects are to ensure controllable substrate thickness, uniform microstructure and high batch stability.

[0029] Thirdly, this embodiment provides an application of collagen membrane substrate in the field of biomedical materials. Experimental results show that the collagen membrane substrate prepared in the above embodiment exhibits good biocompatibility and antioxidant microenvironment regulation effects in models such as tissue engineering scaffolds, drug sustained-release carriers, and wound dressing matrices. Therefore, it can be used to prepare biomedical materials that require both biodegradability and programmable functionality for prevention and / or treatment.

[0030] Fourthly, this embodiment provides a double-sided self-growing hydrogel. A thermally responsive monomer solution and an antibacterial and antioxidant monomer solution are respectively coated onto both sides of a substrate; wherein the substrate is the collagen membrane substrate provided in the first embodiment. In this embodiment, by coating different functional monomer solutions onto both sides of an active substrate, the Fe embedded in the substrate is utilized... 3+ The laccosin coordination system, acting as an endogenous initiator, simultaneously initiates in-situ free radical polymerization of monomers on both sides, enabling the one-step construction of a bifacial structure with differentiated functions on the same substrate. This solves the problem of integrating different functions on both sides of the same material and the complexity of the process in existing technologies, resulting in an asymmetric smart material with rapid thermal response shrinkage on one side and efficient antibacterial and antioxidant capabilities on the other.

[0031] Fifthly, this embodiment provides a method for preparing a double-sided self-growing hydrogel. The preparation steps of the thermally responsive monomer solution include: dissolving the thermally responsive monomer, the first initiator, and the first crosslinking agent in deionized water at a mass ratio of 120:5:5~130:15:15; the preparation steps of the antibacterial and antioxidant monomer solution include: dissolving the antibacterial monomer, the antioxidant monomer, the second initiator, and the second crosslinking agent in deionized water at a mass ratio of 200:200:15:15~210:220:25:25; coating includes uniform spraying followed by allowing self-growth for 5~10 minutes. In this embodiment, by limiting the specific composition and self-growth time of the monomer solutions on both sides, the redox initiation system in the substrate achieves rapid polymerization of the monomers under mild conditions, enabling the two functional monomer solutions to form a micron-scale liquid film on the substrate surface and complete gelation within a kinetic window of 5~10 minutes. This precisely controls the thickness and crosslinking density of the hydrogel layers on both sides, thereby ensuring interfacial bonding strength while avoiding embrittlement caused by excessive crosslinking, ensuring that the double-sided hydrogel has good interfacial bonding and functional stability.

[0032] As a specific embodiment, this invention provides a selection of chemical components for a double-sided self-growing hydrogel. The thermally responsive monomer is N,N-diethylacrylamide (DEA); the antibacterial monomer is methacryloyloxyethyltrimethylammonium chloride (DMC); the antioxidant monomer is N-(3,4-dihydroxyphenylethyl)methacrylamide (DMA); both the first and second initiators are ammonium persulfate (APS); and both the first and second crosslinking agents are N,N'-methylenebisacrylamide (MBA). In this embodiment, DEA is set as the thermally responsive monomer to provide the lowest critical solution temperature (LCST) phase transition characteristics near body temperature, DMC as the antibacterial monomer to provide cationic bactericidal ability, and DMA as the antioxidant monomer to provide catechol free radical scavenging ability. Furthermore, APS / MBA is used as the initiation / crosslinking system, which can interact with Fe in the substrate. 3+ / The synergistic initiation effect of rosin solves the problems of functional limitations and low polymerization efficiency of single monomers. Its beneficial effect is that the chemical structure of each monomer is precisely matched with the target function, and the synergistic matrix initiation system realizes the simultaneous optimization of multiple biological activities and intelligent response performance.

[0033] As a specific implementation, this invention provides a preferred formulation ratio for a double-sided self-growing hydrogel. The mass ratio of the thermally responsive monomer, the first initiator, and the first crosslinking agent is 127:10:10; the mass ratio of the antibacterial monomer, the antioxidant monomer, the second initiator, and the second crosslinking agent is 207:221:20:20. By limiting the above precise mass ratio, the crosslinking density and functional group distribution of the polymer network can be controlled, enabling the formation of a dense network on the thermally responsive side to ensure rapid shrinkage driving force, and achieving the optimal synergistic ratio between monomers on the antibacterial and antioxidant side. This solves the problem of poor mechanical properties or insufficient functional expression caused by improper formulation. Experimental data shows that the hydrogel obtained under this formulation has a significantly shortened thermal response time and a significantly improved antibacterial rate, proving the scientific validity and effectiveness of the parameter selection.

[0034] Sixthly, this embodiment provides an application of a double-sided self-growing hydrogel in the field of biomedical materials. In this embodiment, by applying the double-sided self-growing hydrogel to the field of biomedical materials, based on its asymmetric functional characteristics of thermally responsive shrinkage on one side and antibacterial and antioxidant properties on the other, the synergy of intelligent response and biological protection of the material is realized, thereby broadening the application scope of intelligent hydrogels in high-end medical fields such as wound dressings and actuation devices.

[0035] As a specific implementation, this embodiment provides an application of the double-sided self-growing hydrogel in any of the above embodiments for the preparation of one or more of the following: biomedical dressings, soft actuators, or smart responsive materials. In this invention, the thermal shrinkage properties of one side of the double-sided hydrogel provide driving force, while the antibacterial and antioxidant properties of the other side provide biological protection. This allows for flexible adaptation to the needs of different application scenarios, thereby achieving a deep coupling between material function and application scenario. Each specific application is supported by sufficient performance data, enhancing the targeted nature of patent protection and commercial value.

[0036] Unless otherwise specified, all materials, reagents and instruments used in the embodiments of this invention can be obtained through commercial channels.

[0037] Materials and reagents: Fisetin (purity ≥98%), ferric chloride hexahydrate (FeCl3·6H2O, purity ≥99%), collagen (type I, derived from bovine Achilles tendon), N,N-diethylacrylamide (DEA, purity ≥98%), N-(3,4-dihydroxyphenylethyl)methacrylamide (DMA, purity ≥97%), methacryloyloxyethyltrimethylammonium chloride (DMC, purity ≥80%), ammonium persulfate (APS, purity ≥98%), N,N'-methylenebisacrylamide (MBA, purity ≥99%), glacial acetic acid (analytical grade).

[0038] Instruments and equipment: Vacuum drying oven (DZF-6050, Gongyi Yuhua Instrument Co., Ltd.), electronic balance (BSA224S, Sartorius Scientific Instruments Beijing Co., Ltd.), ultrasonic cleaner (KQ-500DE, Kunshan Ultrasonic Instrument Co., Ltd.), field emission scanning electron microscope (SU8010, Hitachi High Technology Co., Ltd.), ultraviolet-visible spectrophotometer (UV-2600, Shimadzu Enterprise Management China Co., Ltd.).

[0039] Example 1: This embodiment provides a method for preparing and verifying a double-sided self-growing collagen hydrogel.

[0040] 10 mg of flavin and 27 mg of FeCl3·6H2O were placed in 10 mL of deionized water. A small amount of NaOH solution was added dropwise to adjust the pH to weakly alkaline (7.9~8.3) to promote coordination. The mixture was sonicated for 15 min until completely dissolved, forming a dark black, transparent flavin-iron coordination solution. Collagen was dissolved in 0.5 mol / L acetic acid solution under light-protected conditions to prepare a collagen solution with a concentration of 40 mg / mL. The prepared flavin-iron coordination solution was added to the collagen solution at a volume ratio of 2:5, and sonicated for 10 min to ensure homogeneity. The mixture was poured into a flat-bottomed polytetrafluoroethylene mold and dried in a vacuum drying oven at 50℃ for 5 h to obtain uniform, dense collagen sheets with a thickness of approximately 0.2~0.5 mm. Figure 1 As shown, Figure 1 The macroscopic morphology of the collagen membrane substrate prepared in Example 1 is shown. It can be seen that the substrate is black, with a smooth surface without cracks and good flexibility.

[0041] Dissolve 127 mg DEA, 10 mg APS, and 10 mg MBA in 10 mL of deionized water and stir to obtain solution A; dissolve 221 mg DMA, 207 mg DMC, 20 mg APS, and 20 mg MBA in 20 mL of deionized water and stir to obtain solution B.

[0042] The prepared collagen sheets were fixed horizontally, and solution A was evenly sprayed onto the upper surface of the sheets using a micro-sprayer. The sheets were immediately flipped over, and solution B was evenly sprayed onto the lower surface. The mixture was allowed to stand at room temperature for 8 minutes, utilizing the Fe within the substrate... 3+ The laccoside system initiates in-situ polymerization of monomers on both sides. After the reaction, the unreacted monomers on the surface are gently rinsed with deionized water to obtain a double-sided self-growing hydrogel. Figure 2 As shown, Figure 2 The cross-sectional SEM morphology of the product of Example 1 is shown, which clearly shows the dense collagen basal layer in the middle and the loose and porous hydrogel growth layers on both sides. The interface is tightly bound without obvious delamination, which confirms the successful construction of covalent anchoring.

[0043] The total thickness of the resulting hydrogel is approximately 0.8–1 mm, and the thicknesses of the functional layers on both sides are basically symmetrical.

[0044] This embodiment successfully prepared a double-sided self-growing hydrogel with a well-defined double-layer structure. The process was controllable, and the product structure was complete, verifying the feasibility of the core technical solution.

[0045] Example 2: This embodiment aims to verify the impact of drying conditions on substrate quality and subsequent self-growth effect.

[0046] With all other preparation conditions the same as in Example 1, only the vacuum drying temperature was adjusted from 50°C to 40°C and the drying time was extended to 6 h to obtain collagen sheets, and then double-sided spraying self-growth operation was carried out (reaction time 8 min).

[0047] The resulting substrate surface was uniform with no obvious shrinkage cracks, but the water content was slightly higher than in Example 1. The hydrogel layer that subsequently grew was structurally intact, with a thermal shrinkage response time of 6 s and an antibacterial rate of 69%.

[0048] The results show that the technical solution of the present invention can still achieve good film-forming properties and functionalization effects under low-temperature drying conditions of 40℃.

[0049] Example 3: This embodiment aims to verify the impact of drying conditions on substrate quality and subsequent self-growth effect.

[0050] With other preparation conditions the same as in Example 1, only the vacuum drying temperature was adjusted from 50°C to 60°C and the drying time was shortened to 4 h to obtain collagen sheets, and then double-sided spraying self-growth operation was carried out (reaction time 8 min).

[0051] The resulting substrate was slightly darker in color and slightly harder in texture, but no charring was observed. The hydrogel layer that subsequently grew adhered firmly, with a thermal shrinkage response time of 5 seconds and an antibacterial rate of 70%.

[0052] The results showed that collagen did not undergo severe denaturation under high-temperature drying conditions of 60℃, and the coordination system still maintained high activity.

[0053] Example 4: This embodiment aims to verify the effect of self-growth time parameters on the performance of hydrogel layers.

[0054] With all other preparation conditions the same as in Example 1, only the self-growth reaction time after double-sided spraying was adjusted from 8 min to 5 min, while the other conditions remained unchanged, to obtain a double-sided self-growing hydrogel.

[0055] Cross-sectional SEM showed that the hydrogel layers on both sides had formed a continuous network, but the thickness was slightly thinner than in Example 1. Performance tests showed that the thermal shrinkage response time was 5 s and the antibacterial rate was 68%.

[0056] The results show that even within a relatively short reaction time of 5 minutes, the monomers can fully polymerize to form a functional layer and achieve the expected technical effect.

[0057] Example 5: This embodiment aims to verify the effect of self-growth time parameters on the performance of hydrogel layers.

[0058] With all other preparation conditions the same as in Example 1, only the self-growth reaction time after double-sided spraying was adjusted from 8 min to 10 min, while the other conditions remained unchanged, to obtain a double-sided self-growing hydrogel.

[0059] The thickness of the hydrogel layer was further increased, and the mechanical strength was slightly improved, but the thermal response speed and antibacterial performance were not significantly different from those in Example 1 (response time 4 s, antibacterial rate 70%).

[0060] The results showed that extending the reaction time to 10 min still yielded excellent performance, with no side reactions or performance degradation.

[0061] Example 6: This embodiment comprehensively characterizes and verifies the performance of the double-sided self-growing hydrogel prepared in Example 1, and compares it with the control group.

[0062] Example 7: Control group 1 (blank substrate group): Thin sheets were prepared using only pure collagen solution and vacuum dried, without rosin or Fe. 3+ The remaining processing is the same as in Example 1.

[0063] Control group 2 (no substrate initiation group): The substrate of Example 1 was used, but no APS initiator was added to the monomer solution. The reaction was initiated solely by the substrate, and the occurrence of the reaction was observed.

[0064] Control group 3 (commercially available ordinary hydrogel group): commercially available ordinary collagen dressing (Kefumei Medical Recombinant Collagen Repair Dressing, purchased from Giant Biotech Co., Ltd.) was purchased as a control.

[0065] Test items and results 1. Thermal response shrinkage properties: Immerse the sample in phosphate buffer at 37°C and record the change in shrinkage rate over time.

[0066] 2. Antibacterial properties: The colony counting method was used to test the inhibition rate of the samples against Escherichia coli and Staphylococcus aureus.

[0067] 3. Antioxidant properties: The free radical scavenging rate of the sample extract was determined using the ABTS free radical scavenging method and the DPPH free radical scavenging method.

[0068] 4. Biocompatibility: The survival rate of L929 cells in the sample extract was detected by the MTT assay.

[0069] The specific test results are shown in Table 1.

[0070] Table 1. Performance test results of double-sided self-growing hydrogels

[0071] As shown in Table 1, the hydrogels prepared in Examples 1-5 all exhibited excellent thermal response shrinkage properties (shrinkage rate >80% within 30 s), highly efficient broad-spectrum antibacterial activity (bacterial inhibition rate >68%), and significant antioxidant capacity (ABTS scavenging rate >64%, DPPH scavenging rate >65%), and cell viability was all above 90%, indicating that the materials have good biocompatibility. In contrast, Control Group 1 lacked an initiation system and could not grow a functional layer, exhibiting almost no thermal response or antibacterial function; Control Group 2 lacked an exogenous initiator and the substrate did not contain initiating components. The commercially available product in Control Group 3 had a single function, and its overall performance was far inferior to that of this invention.

[0072] like Figure 3 As shown, Figure 3 The bar chart shows the thermal response shrinkage rate of the double-sided hydrogel at different temperatures. This result indicates that as the ambient temperature rises to 37°C, the shrinkage rate of the sample from Example 1 increases rapidly, and its shrinkage response time is ≤30 s, confirming its rapid thermal response characteristics. Figure 4 As shown, Figure 4 The figures show the test results and inhibition rate statistics of the double-sided hydrogel against Escherichia coli and Staphylococcus aureus. It is clearly visible from the figures that the number of colonies in Example 1 group was significantly less than that in the control group, and the inhibition zone was clear. This confirms that the synergistic effect of DMC and DMA endows the material with strong bactericidal ability. Figure 5 As shown, Figure 5 The figure shows the test results of DPPH and ABTS free radical scavenging rates of the double-sided hydrogel. These results indicate that the material possesses free radical scavenging ability, reflecting the synergistic antioxidant mechanism of the rutin and catechol structures. Figure 6 As shown, Figure 6 The graph shows the cell viability test results for the double-sided hydrogel. The data indicates that the cell viability in each example group remained at a high level, confirming the excellent biocompatibility of the material. Furthermore, as... Figure 7 As shown, Figure 7 The chemical structure diagrams of the double-sided self-growing collagen hydrogel thermal response layer [structural formula (1)] and antibacterial and antioxidant layer [structural formula (2)] of Example 1 are shown, clearly revealing the molecular composition and connection mode of the two functional layers, providing a structural basis for the above-mentioned performance.

[0073] This embodiment, through systematic performance testing and comparative group analysis, fully demonstrates that the double-sided self-growing hydrogel prepared by the present invention has significant synergistic advantages in terms of thermal response, antibacterial properties, antioxidant properties, and biocompatibility, solving the problem of single function in existing technologies and possessing extremely high potential for clinical application.

[0074] Experimental results show that the double-sided self-growing hydrogel prepared in this invention exhibits rapid reversible thermal shrinkage behavior in a simulated body fluid environment, demonstrates an antibacterial effect of over 70% in a bacterial co-culture model, shows significant antioxidant activity in free radical scavenging experiments, and exhibits good biocompatibility in cytotoxicity tests. Therefore, this double-sided self-growing hydrogel can be used to prepare biomedical dressings, soft actuators, or smart responsive materials, and has unique application value, especially in complex wound repair scenarios requiring both temperature-driven deformation and anti-infection / antioxidant protection.

[0075] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A collagen membrane substrate, characterized in that, Fe, including laccasein, is coordinated. 3+ It is prepared by combining raw materials such as collagen.

2. A method for preparing the collagen membrane substrate according to claim 1, characterized in that, Includes the following steps: Mix lacryma-jobi with Fe 3+ The donor, in ionic form, is complexed with collagen in an acetic acid solution at a pH of 7.9–8.3 and then uniformly mixed with the collagen in acetic acid solution. The collagen membrane substrate is obtained by molding and vacuum drying.

3. The preparation method according to claim 2, characterized in that, The Fe 3+ The donor is FeCl3·6H2O; the mass ratio of the laccoside to the FeCl3·6H2O is 10:

27. The concentration of collagen in the acetic acid solution is 40 mg / mL. The drying conditions are: temperature 40~60℃, duration 4~6h.

4. The application of the collagen membrane substrate according to claim 1 in the field of biomedical materials.

5. A double-sided self-growing hydrogel, characterized in that, The thermally responsive monomer solution and the antibacterial and antioxidant monomer solution were coated on both sides of the substrate, respectively. Wherein, the substrate is the collagen membrane substrate according to claim 1.

6. A method for preparing the double-sided self-growing hydrogel according to claim 5, characterized in that, The preparation steps of the thermally responsive monomer solution include: dissolving the thermally responsive monomer, the first initiator, and the first crosslinking agent in deionized water at a mass ratio of 120:5:5 to 130:15:15; The preparation steps of the antibacterial and antioxidant monomer solution include: dissolving the antibacterial monomer, antioxidant monomer, second initiator and second crosslinking agent in deionized water at a mass ratio of 200:200:15:15 to 210:220:25:25; The coating process includes the following steps: uniformly spraying the coating and allowing it to grow on its own for 5-10 minutes.

7. The preparation method according to claim 6, characterized in that, The thermally responsive monomer is N,N-diethylacrylamide; The antibacterial monomer is methacryloyloxyethyltrimethylammonium chloride; The antioxidant monomer is N-(3,4-dihydroxyphenylethyl)methacrylamide; Both the first initiator and the second initiator are ammonium persulfate; Both the first crosslinking agent and the second crosslinking agent are N,N'-methylenebisacrylamide.

8. The preparation method according to claim 6, characterized in that, The mass ratio of the thermally responsive monomer, the first initiator, and the first crosslinking agent is 127:10:10; The mass ratio of the antibacterial monomer, the antioxidant monomer, the second initiator, and the second crosslinking agent is 207:221:20:

20.

9. The application of the double-sided self-growing hydrogel according to claim 5 in the field of biomedical materials.

10. The application according to claim 9, characterized in that, The double-sided self-growing hydrogel is used to prepare any one or more of the following: biomedical dressings, soft actuators, or smart responsive materials.

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