Microenvironment adaptive cell population-like hydrophobic hydrogel as well as preparation method and application thereof

Abstract

The invention relates to the technical field of biomedical materials, in particular to microenvironment adaptive cell population-like hydrophobic hydrogel as well as a preparation method and application thereof. The microenvironment adaptive cell population-like hydrophobic hydrogel is prepared from methyl acrylate, 4-vinyl aniline, 4-vinyl benzaldehyde, a cross-linking agent and an initiator through an initiation polymerization reaction, and is loaded with multifunctional traditional Chinese medicine active ingredients. The invention provides the hydrophobic hydrogel which has microenvironment self-adaptive capability, can simulate an immune cell population behavior mode and can realize long-acting moisturizing and intelligent drug release, and the multifunctional traditional Chinese medicine components loaded on the hydrogel have multiple effects of resisting bacteria, inflammation and oxidation, promoting angiogenesis and the like, and have a synergistic effect with the microenvironment response characteristic of the hydrogel, so that the hydrogel has a good application prospect. The treatment effect on a biological membrane infected wound surface can be obviously improved.

Description

Technical Field

[0001] This application relates to the field of biomedical materials technology, and in particular to a microenvironment-adaptive cell-group hydrophobic hydrogel, its preparation method, and its application. Background Technology

[0002] Chronic wound infections, especially refractory infections resulting from bacterial biofilm formation, pose a significant challenge to clinical wound management. Biofilms not only enhance bacterial resistance but also continuously trigger excessive inflammatory responses, hindering the normal wound healing process. Traditional clinical dressings—hydrophilic hydrogels—while possessing some moisturizing and drug-carrying capacity, often lack environmental responsiveness in their drug release behavior, failing to achieve on-demand drug release. This can lead to premature drug release, low utilization rates, and even induce drug resistance. Furthermore, some current responsive gels may prolong the inflammatory response during degradation, thereby interfering with healing.

[0003] In addition, current gel materials have the following obvious limitations in terms of structure and function biomimicry: it is difficult to simulate the recognition-response mechanism of immune cell membranes and cannot achieve intelligent drug regulation and release in complex wound microenvironments (such as pH 4.5-6.5); at the same time, traditional hydrophilic gels have limited drug loading capacity, hydrophobic gels are difficult to load, and their water retention is insufficient, which increases patient pain and treatment costs due to frequent dressing changes. Summary of the Invention

[0004] To address the aforementioned technical problems, this application provides a microenvironment-adaptive cell population-like hydrophobic hydrogel, its preparation method, and its application. It provides a hydrophobic hydrogel with microenvironment adaptability, capable of mimicking the behavior of immune cell populations, and achieving long-lasting moisturizing and intelligent drug release. The multifunctional traditional Chinese medicine components loaded in this hydrogel possess multiple effects, including antibacterial, anti-inflammatory, antioxidant, and angiogenesis-promoting properties. These components work synergistically with the microenvironment-responsive characteristics of the hydrogel to significantly improve the therapeutic effect on biofilm-infected wounds.

[0005] A microenvironment-adaptive cell population-like hydrophobic hydrogel: The microenvironment-adaptive cell cluster hydrophobic hydrogel was prepared by initiating polymerization of methyl acrylate, 4-vinylaniline, 4-vinylbenzaldehyde, crosslinking agent and initiator, and loaded with multifunctional active ingredients of traditional Chinese medicine.

[0006] Preferably, the methyl acrylate, 4-vinylaniline, and 4-vinylbenzaldehyde are uniformly dispersed and dissolved in dimethyl sulfoxide to form a prepolymer solution. A crosslinking agent and an initiator are added to the prepolymer solution to initiate a polymerization reaction and form a solid organic gel. The solid organic gel is placed in excess dimethyl sulfoxide and washed and swollen to form a purified organic gel. The purified organic gel is loaded with multifunctional traditional Chinese medicine active ingredients to form a drug-loaded organic gel. The drug-loaded organic gel is immersed in deionized water to perform solvent replacement, inducing phase separation and swelling of the hydrophobic polymer network to form a microenvironment-adaptive cell-like hydrophobic hydrogel.

[0007] Preferably, the methyl acrylate in the prepolymer solution has a mass fraction of 15% to 25%, the molar ratio of 4-vinylaniline to 4-vinylbenzaldehyde is 1:1, and the molar ratio of 4-vinylaniline, 4-vinylbenzaldehyde, and methyl acrylate is (1:1:98) to (1:1:8); the crosslinking agent is 1,4-butanediol diacrylate, and the mass fraction of 1,4-butanediol diacrylate in the prepolymer solution is 0% to 1%; the initiator is diphenylphosphine oxide, and the mass fraction of the initiator in the prepolymer solution is 0.05% to 0.5%.

[0008] Preferably, the multifunctional active ingredient of the traditional Chinese medicine is at least one of berberine hydrochloride, quercetin, luteolin, rhein, resveratrol, magnolol, curcumin, and derivatives of each ingredient.

[0009] Preferably, the mass fraction of the multifunctional active ingredient in traditional Chinese medicine is 0.1% to 2%.

[0010] Preferably, the volume ratio of the drug-loaded organic gel to the deionized water is 1:(50-100), the drug-loaded organic gel is soaked in excess deionized water for 24-72 hours, and the drug-loaded organic gel is left to stand in excess deionized water at room temperature.

[0011] A method for preparing a microenvironment-adaptive cell population-like hydrophobic hydrogel, comprising the following steps: Preparation of the organic gel: The organic gel was prepared by free radical polymerization initiated by ultraviolet light. Methyl acrylate, 4-vinylaniline, 4-vinylbenzaldehyde and 1,4-butanediol diacrylate were weighed according to the formula ratio and dissolved in dimethyl sulfoxide to form a mixed solution. The mixed solution was ultrasonically treated until fully dissolved and then protected from light. Diphenylphosphine oxide was weighed according to the formula ratio and added to the mixed solution and dissolved to obtain a homogeneous and transparent prepolymer solution. The prepolymer solution was subjected to an initiation polymerization reaction under ultraviolet light to form a solid organic gel. The solid organic gel was immersed in excess dimethyl sulfoxide to elute unreacted monomers and allow the gel to fully swell and reach equilibrium to obtain the purified organic gel. Preparation of cell cluster hydrophobic hydrogel: Step 1, 4-vinylaniline, 4-vinylbenzaldehyde, methyl acrylate (15%–25% by mass), 1,4-butanediol diacrylate (0%–1% by mass), and diphenylphosphine oxide (0.05%–0.5% by mass) are dissolved in dimethyl sulfoxide to form a prepolymer solution. The molar ratio of 4-vinylaniline, 4-vinylbenzaldehyde, and methyl acrylate is (1:1:98) to (1:1:8). The prepolymer solution is subjected to an initiation polymerization reaction under ultraviolet light to form a solid organic gel. The solid organic gel is then immersed in a dimethyl sulfoxide drug mixture containing multifunctional traditional Chinese medicine active ingredients for 6 to 48 hours to obtain a drug-loaded organic gel. Step 2: The drug-loaded organic gel is immersed in excess deionized water at room temperature for 24h to 72h, with the volume ratio of the drug-loaded organic gel to the deionized water being 1:(50 to 100), to obtain a microenvironment-adaptive cell population hydrophobic hydrogel.

[0012] Preferably, the molar ratio of 4-vinylaniline to 4-vinylbenzaldehyde is 1:1.

[0013] Preferably, the multifunctional active ingredient of traditional Chinese medicine is at least one of berberine hydrochloride, quercetin, luteolin, rhein, resveratrol, magnolol, curcumin, and derivatives of each ingredient, and the mass fraction of the multifunctional active ingredient of traditional Chinese medicine in the dimethyl sulfoxide drug mixture is 0.1% to 2%.

[0014] Application of a microenvironment-adaptive cell cluster hydrophobic hydrogel: The microenvironment-adaptive cell cluster hydrophobic hydrogel is used in the preparation of wound dressings.

[0015] The beneficial effects of this application are reflected in the formation of pH-sensitive Schiff base bonds between 4-vinylaniline and 4-vinylbenzaldehyde during polymerization. These bonds break in acidic wound microenvironments (e.g., pH 4.5-6.5), triggering on-demand drug release. This overcomes the problems of blind and sudden drug release in traditional gels, constructing a microenvironment-responsive, long-lasting, highly water-retaining, and multi-biologically active cell-like hydrophobic hydrogel, providing a new material strategy for the efficient treatment of biofilm-infected wounds. Through this design, this application provides a hydrophobic hydrogel with microenvironment adaptability, mimicking the behavior of immune cell populations, and achieving long-lasting hydration and intelligent drug release. The multifunctional traditional Chinese medicine components loaded in this hydrogel possess multiple effects such as antibacterial, anti-inflammatory, antioxidant, and angiogenesis-promoting properties. These effects synergistically enhance the therapeutic efficacy for biofilm-infected wounds. Attached Figure Description

[0016] Figure 1 These are schematic diagrams illustrating the microstructures of the blank hydrophobic hydrogel and the microenvironment-adaptive cell population hydrophobic hydrogel provided in the embodiments of this application; wherein, Figure 1 A is an optical microscope image showing the microstructure of the blank hydrophobic hydrogel (left) and the microenvironment-adaptive cell population hydrophobic hydrogel (right) provided in the embodiments of this application. Figure 1 B is a cryo-scanning electron microscopy (Cryo-SEM) schematic diagram of the microenvironment-adaptive cell population hydrophobic hydrogel provided in this embodiment.

[0017] Figure 2 This is a schematic diagram of the water absorption and swelling curve of the microenvironment-adaptive cell population hydrophobic hydrogel provided in the embodiments of this application; Figure 3 This is a schematic diagram of the water loss rate curves of the microenvironment-adaptive cell population hydrophobic hydrogel and the traditional hydrophilic gel provided in the embodiments of this application; Figure 4 This is a schematic diagram illustrating drug release from a microenvironment-adaptive cell population hydrophobic hydrogel provided in an embodiment of this application, wherein... Figure 4 A represents the release curve of berberine hydrochloride (Ber) from Ber@MVV within 24 hours. Figure 4 B represents the long-term release curve of berberine hydrochloride (Ber) in Ber@MVV; Figure 5 This is a 3D hyper-depth-of-field schematic diagram of the microenvironment-adaptive cell population hydrophobic hydrogel provided in the embodiments of this application after incubation in PBS at different pH values, wherein... Figure 5 A is a 3D super-depth-of-field image. Figure 5 B represents the corresponding average roughness assessment; Figure 6This is a schematic diagram illustrating the in vitro antibacterial effect of the microenvironment-adaptive cell population hydrophobic hydrogel provided in the embodiments of this application, wherein... Figure 6 A is a photograph of the inhibition zone of the gel against Escherichia coli and Staphylococcus aureus. Figure 6 B is a statistical chart showing the diameter of Staphylococcus aureus cells inhibited. Figure 6 C represents the statistical graph of the diameter of inhibited E. coli. Figure 6 D is a physical diagram of inhibited biofilm formation. Figure 6 E represents a quantitative diagram of Staphylococcus aureus biofilm inhibition. Figure 6 F represents the quantitative graph of Escherichia coli biofilm inhibition; Figure 7 This is a schematic diagram illustrating the role of the microenvironment-adaptive cell population hydrophobic hydrogel in scavenging ROS, as provided in the embodiments of this application. Figure 7 A is a ROS fluorescence micrograph. Figure 7 B is a quantitative graph of ROS clearance rate; Figure 8 This is a schematic diagram illustrating the therapeutic effect of biofilm on infected wounds provided in the embodiments of this application. Figure 8 A shows the wound healing at different time points. Figure 8 B is a thermal image of wound healing. Figure 8 C represents the wound healing curve; Figure 9 This is a schematic diagram illustrating the antibacterial effect of biofilm in infected wounds provided in the embodiments of this application. Figure 9 A shows actual images of bacterial coatings at different time points. Figure 9 B represents the bacterial survival rate curve. Figure 9 C is a representative diagram of Gram staining. Detailed Implementation

[0018] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0019] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0020] In the description of this application, the use of "first" and "second" is for the purpose of distinguishing technical features only, and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the order of the technical features indicated.

[0021] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0022] This application proposes a microenvironment-adaptive cell population hydrophobic hydrogel, its preparation method, and its application. The embodiments of this application are further described below with reference to the accompanying drawings.

[0023] Reference Figure 1 , Figure 1 This application illustrates a microenvironment-adaptive cell-group hydrophobic hydrogel, which is prepared by an initiation polymerization reaction of methyl acrylate, 4-vinylaniline, 4-vinylbenzaldehyde, a crosslinking agent, and an initiator.

[0024] Understandably, methyl acrylate, 4-vinylaniline, and 4-vinylbenzaldehyde are uniformly dispersed and dissolved in dimethyl sulfoxide to form a prepolymer solution, loaded with multifunctional active ingredients of traditional Chinese medicine. A crosslinking agent and an initiator are added to the prepolymer solution to initiate a polymerization reaction and form a solid organic gel. The solid organic gel is placed in excess dimethyl sulfoxide and washed and swollen to form a purified organic gel. The purified organic gel is loaded with multifunctional active ingredients of traditional Chinese medicine to form a drug-loaded organic gel. The drug-loaded organic gel is immersed in deionized water to perform solvent replacement, inducing phase separation and swelling of the hydrophobic polymer network to form a microenvironment-adaptive cell-like hydrophobic hydrogel.

[0025] It should be noted that methyl acrylate (MA) is used as the main monomer, and 4-vinylaniline (VA) and 4-vinylbenzaldehyde (VB) are added. In the presence of a crosslinking agent (BDA) and an initiator (TPO), polymerization is initiated by ultraviolet light in DMSO solvent to form a solid organic gel with a three-dimensional network structure. The above solid organic gel is then immersed in a DMSO solution containing dissolved active ingredients of traditional Chinese medicine (such as berberine hydrochloride). The drug molecules are diffused and encapsulated in the gel network by a physical impregnation method to obtain a drug-loaded organic gel.

[0026] It's important to note that when the drug-loaded organic gel is immersed in a large amount of deionized water, a crucial "solvent displacement" process occurs: DMSO is replaced by water, and the hydrophobic polymer chains undergo phase separation in the water, self-assembling to form a dense, cell-membrane-like surface layer. This ultimately yields a cell-like hydrophobic hydrogel product with microenvironment-responsive capabilities. When this final hydrogel is applied to chronic wounds (such as biofilm-infected wounds), the hydrogel structure remains stable in the normal wound microenvironment (pH≈7.4), allowing for slow drug release. However, in the presence of bacterial biofilms, their metabolism causes the local microenvironment to become acidic (pH≈4.5-6.5), triggering the hydrogel's intelligent response mechanism, accelerating drug release, killing pathogens, and promoting healing.

[0027] It should be noted that the hydrogel provided in this application is hydrophobic. During the final solvent replacement (DMSO→water) process, the hydrophobic polymer chains undergo intense phase separation and self-assembly to avoid the aqueous environment, forming numerous tightly packed, cell-membrane-like hydrophobic microdomains on the surface and inside (see...). Figure 1 These microdomains act like tiny warehouses, effectively encapsulating and storing hydrophobic drug molecules (such as berberine hydrochloride), significantly improving drug loading and storage stability. Simultaneously, the overall network structure of the gel absorbs and locks in large amounts of water, thus exhibiting excellent water retention properties (see...). Figure 4 This provides a moist environment for wound healing.

[0028] Specifically, the pH-responsive smart drug release principle (mimicking immune cells) hinges on 4-vinylaniline (VA) and 4-vinylbenzaldehyde (VB) in the polymer monomers: during polymerization, the amino group of VA... It reacts with the aldehyde group (-CHO) of VB to form a Schiff base (-N=C-). This chemical bond acts as a "smart gating" and structural support for connecting molecular chains. Schiff bases are characterized by being "alkaline-loving and acid-sensitive". They are stable in a neutral environment (pH 7.4) but break rapidly in an acidic environment (pH 5.5).

[0029] For example, when a bacterial biofilm exists in a wound, bacterial metabolism produces acidic substances, leading to a decrease in the pH of the wound microenvironment. This acidic environment stimulates the hydrogel, causing the Schiff base bonds within it to break. The breaking of the Schiff bases results in pores and channels appearing in the originally dense "cell membrane-like" hydrophobic structure (see...). Figure 6 The drugs encapsulated inside (A, B) are released in large quantities through these newly formed channels, acting directly on the pathogens. This mimics the natural defense mechanism of immune cells being activated by pathogens, recognizing signals and releasing antimicrobial factors.

[0030] Understandably, the mass fraction of methyl acrylate in the prepolymer solution is 15%–25%, the molar ratio of 4-vinylaniline to 4-vinylbenzaldehyde is 1:1, and the molar ratio of 4-vinylaniline, 4-vinylbenzaldehyde, and methyl acrylate is (1:1:98)–(1:1:8); the crosslinking agent is 1,4-butanediol diacrylate, and the mass fraction of 1,4-butanediol diacrylate in the prepolymer solution is 0%–1%; the initiator is diphenylphosphine oxide, and the mass fraction of the initiator in the prepolymer solution is 0.05%–0.5%.

[0031] It is understandable that the active ingredients of multifunctional traditional Chinese medicine are at least one of berberine hydrochloride, quercetin, luteolin, rhein, resveratrol, magnolol, curcumin, and derivatives of each ingredient.

[0032] It is understandable that the mass fraction of the active ingredients in multifunctional traditional Chinese medicine is 0.1% to 2%.

[0033] It should be noted that 0.1% to 2% of berberine hydrochloride was dissolved in dimethyl sulfoxide to obtain a drug mixture; the solid organic gel was immersed in the drug mixture for 6 to 48 hours, and then transferred to excess deionized water for 24 to 72 hours to obtain a microenvironment-adaptive cell population hydrophobic hydrogel.

[0034] It should be noted that the drug loading rates of the organic gel impregnated in drug mixtures with mass fractions of 1% and 2%, and after 24 hours and 48 hours of impregnation, showed little difference. Furthermore, a significant amount of organic solvent remained in the solid organic gel after 24 hours of immersion in deionized water, while excessive drug loss occurred after 72 hours. Considering the cost of the hydrophobic hydrogel, the residual organic solvent rate, and the drug loading rate, the optimal choice for preparing the microenvironment-adaptive cell population hydrophobic hydrogel was a 1% drug mixture, with the organic gel impregnated in the drug mixture for 24 hours and then in deionized water for 48 hours. The preparation of the blank hydrophobic hydrogel did not involve the drug impregnation step. Cross-sectional laser microscope images of the blank hydrophobic hydrogel (MVV) and the drug-loaded cell population hydrophobic hydrogel, i.e., the microenvironment-adaptive cell population hydrophobic hydrogel (Ber@MVV), are shown below. Figure 1 It can be observed that both MVV and Ber@MVV are composed of abundant and dense cell-like structures, which also proves that the drug loading does not affect their structure.

[0035] It should be noted that, Figure 1In this context, Cryo-SEM refers to cryo-scanning electron microscopy, MVV cell cluster-mimetichydrogel refers to microenvironment-adaptive cell cluster hydrophobic hydrogel, and Microscope refers to optical microscopy. Microenvironment-adaptive cell cluster hydrophobic hydrogel has the microstructure and function of cell clusters, thereby promoting the repair of infected wounds.

[0036] For example, the purified organic gel was soaked in a drug mixture containing multifunctional active ingredients of traditional Chinese medicine for 24 hours; a 1% mass fraction of berberine hydrochloride DMSO solution was prepared (i.e., 1g of drug dissolved in 99g of DMSO), and the purified organic gel was soaked in this drug solution and left to stand at room temperature for 24 hours to allow the drug molecules to fully diffuse and load into the gel network. The gel was then removed to obtain the drug-loaded organic gel.

[0037] It is understandable that the volume ratio of drug-loaded organic gel to deionized water is 1:(50-100), the drug-loaded organic gel is soaked in excess deionized water for 24-72 hours, and the drug-loaded organic gel is left to stand in excess deionized water at room temperature.

[0038] For example, the preparation of a solid organic gel: 15% methyl acrylate, 0.3% 1,4-butanediol diacrylate, 0.1% diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide, 4-vinylaniline and 4-vinylbenzaldehyde (molar ratio of 4-vinylaniline:4-vinylbenzaldehyde:methyl acrylate 1:1:98, the organic gel was softened and collapsed after irradiation with 365nm ultraviolet light for 5 min.

[0039] For example, the preparation of a solid organic gel: 20% methyl acrylate, 0.6% 1,4-butanediol diacrylate, 0.5% diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide, 4-vinylaniline and 4-vinylbenzaldehyde (molar ratio of 4-vinylaniline: 4-vinylbenzaldehyde: methyl acrylate 1:1:8) were weighed. The organic gel could not swell effectively after being exposed to ultraviolet light for 60 min.

[0040] For example, the preparation of solid organic gel: 20% by mass of methyl acrylate, 1% of 1,4-butanediol diacrylate, 0.2% of diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide, 4-vinylaniline and 4-vinylbenzaldehyde (molar ratio of 4-vinylaniline:4-vinylbenzaldehyde:methyl acrylate 1:1:98) were weighed, and the organic gel was strong and tough after being irradiated with ultraviolet light for 60 min.

[0041] For example, the preparation of solid organic gel: weigh 20% by mass of methyl acrylate, 0.6% of 1,4-butanediol diacrylate, 0.2% of diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide, 4-vinylaniline and 4-vinylbenzaldehyde (molar ratio of 4-vinylaniline: 4-vinylbenzaldehyde: methyl acrylate 1:1:98), and irradiate with ultraviolet light for 60 min.

[0042] It is understandable that the wavelength of ultraviolet light irradiation is 365nm, and the duration of ultraviolet light irradiation is 1min to 90min.

[0043] For example, in a reaction vessel, anhydrous DMSO solvent is added, and the following are dissolved sequentially: methyl acrylate (MA), making it 20% of the total mass of the solution; 4-vinylaniline (VA) and 4-vinylbenzaldehyde (VB), calculated and weighed according to the molar ratio of n(VA):n(VB):n(MA) = 1:1:98; crosslinking agent 1,4-butanediol diacrylate (BDA), making it 0.6% of the total mass of the solution; the above mixed solution is sonicated until all monomers are fully dissolved, and the entire process is carried out in the dark; initiator diphenyl (2,4,6-trimethylbenzoyl)phosphorus oxide (TPO) is added, making it 0.2% of the total mass of the solution, and stirred to dissolve to obtain a homogeneous and transparent prepolymer solution; the prepolymer solution is poured into a mold and irradiated under a 365 nm wavelength ultraviolet lamp for 60 minutes. After irradiation, a solid organic gel is obtained; the solid organic gel is immersed in an excess of DMSO solution to wash away unreacted monomers and allow the gel network to fully swell, resulting in a purified organic gel.

[0044] Chronic wound infections, especially refractory infections resulting from bacterial biofilm formation, pose a significant challenge to clinical wound management. Biofilms not only enhance bacterial resistance but also continuously trigger excessive inflammatory responses, hindering the normal wound healing process. Traditional clinical dressings—hydrophilic hydrogels—while possessing some moisturizing and drug-carrying capacity, often lack environmental responsiveness in their drug release behavior, failing to achieve on-demand drug release. This can lead to premature drug release, low utilization rates, and even induce drug resistance. Furthermore, some current responsive gels may prolong the inflammatory response during degradation, thereby interfering with healing.

[0045] In addition, current gel materials have the following obvious limitations in terms of structure and function biomimicry: it is difficult to simulate the recognition-response mechanism of immune cell membranes and cannot achieve intelligent drug regulation and release in complex wound microenvironments (such as pH 4.5-6.5); at the same time, traditional hydrophilic gels have limited drug loading capacity, hydrophobic gels are difficult to load, and their water retention is insufficient, which increases patient pain and treatment costs due to frequent dressing changes.

[0046] Based on this, this application provides a microenvironment-adaptive cell-population hydrophobic hydrogel. It utilizes the pH-sensitive Schiff base bonds formed during the polymerization of 4-vinylaniline and 4-vinylbenzaldehyde, which break in acidic wound microenvironments (e.g., pH 4.5-6.5), triggering on-demand drug release and overcoming the problems of blind and sudden drug release in traditional gels. By physically impregnating the drug in an organic gel state (DMSO phase), hydrophobic interactions are utilized to efficiently load hydrophobic active ingredients of traditional Chinese medicine, avoiding the disadvantages of low drug loading and easy drug leakage in traditional hydrogels. Solvent displacement (DMSO→water) induces phase separation in the hydrophobic polymer network, forming a dense cell-membrane-like structure. This not only significantly improves water retention and structural stability but also mimics the recognition-response behavior of immune cell membranes, achieving intelligent antibacterial and anti-inflammatory effects. In other words, this application constructs a cell-population hydrophobic hydrogel that is responsive to the microenvironment, provides long-acting drug release, has high water retention, and possesses multiple biological activities, offering a new material strategy for the efficient treatment of biofilm-infected wounds. This application provides a hydrophobic hydrogel with microenvironment adaptability, capable of mimicking immune cell population behavior patterns, and able to achieve long-lasting moisturizing and intelligent drug release through this design.

[0047] Reference Figure 1 This application provides a method for preparing a microenvironment-adaptive cell population hydrophobic hydrogel as described in any of the embodiments of the first aspect above. The method involves the following steps: A method for preparing a microenvironment-adaptive cell population-like hydrophobic hydrogel, comprising the following steps: Preparation of the organic gel: The organic gel was prepared by free radical polymerization initiated by ultraviolet light. Methyl acrylate, 4-vinylaniline, 4-vinylbenzaldehyde and 1,4-butanediol diacrylate were weighed according to the formula ratio and dissolved in dimethyl sulfoxide to form a mixed solution. The mixed solution was sonicated until fully dissolved and then protected from light. Diphenylphosphine oxide was weighed according to the formula ratio and added to the mixed solution and dissolved to obtain a homogeneous and transparent prepolymer solution. The prepolymer solution was subjected to an initiation polymerization reaction under ultraviolet light to form a solid organic gel. The solid organic gel was immersed in excess dimethyl sulfoxide to elute unreacted monomers and allow the gel to fully swell and reach equilibrium to obtain the purified organic gel. Preparation of cell cluster hydrophobic hydrogel: Step 1, 4-vinylaniline, 4-vinylbenzaldehyde, methyl acrylate (15%–25% by mass), 1,4-butanediol diacrylate (0%–1% by mass), and diphenylphosphine oxide (0.05%–0.5% by mass) are dissolved in dimethyl sulfoxide to form a prepolymer solution. The molar ratio of 4-vinylaniline, 4-vinylbenzaldehyde, and methyl acrylate is (1:1:98) to (1:1:8). The prepolymer solution is subjected to an initiation polymerization reaction under ultraviolet light to form a solid organic gel. The solid organic gel is then immersed in a dimethyl sulfoxide drug mixture containing multifunctional traditional Chinese medicine active ingredients for 6 to 48 hours to obtain a drug-loaded organic gel. Step 2: Soak the drug-loaded organic gel in excess deionized water at room temperature for 24-72 hours. The volume ratio of the drug-loaded organic gel to deionized water is 1:(50-100) to obtain a microenvironment-adaptive cell population hydrophobic hydrogel.

[0048] For example, the drug-loaded organic gel is immersed in a large amount of deionized water (the ratio of gel to water is 1:75); it is left to stand at room temperature (25°C) for 48 hours. During this period, the DMSO inside the gel will gradually diffuse into the water, and water molecules will enter the gel network. Since the polymer chains are hydrophobic, phase separation occurs in the aqueous environment, and they are rearranged and reassembled, eventually forming a drug-loaded cell cluster hydrophobic hydrogel with a microscopic "cell cluster" structure, that is, a microenvironment-adaptive cell cluster hydrophobic hydrogel.

[0049] In one possible implementation, the molar ratio of 4-vinylaniline to 4-vinylbenzaldehyde is 1:1.

[0050] It should be noted that the organic gel was prepared as follows: 15%–25% methyl acrylate, 0%–1% 1,4-butanediol diacrylate, and 0.05%–0.5% diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide were weighed and dissolved in anhydrous dimethyl sulfoxide (DMSO) solution. 4-Vinylaniline and 4-vinylbenzaldehyde were weighed according to a molar ratio of 1:1:(8–98) and added to the DMSO solvent to dissolve completely. The solution was then irradiated under a 365 nm UV lamp for 1–90 min to obtain a solid organic gel.

[0051] For example, the preparation of solid organic gel: 15% methyl acrylate, 0.3% 1,4-butanediol diacrylate, 0.1% diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide, 4-vinylaniline and 4-vinylbenzaldehyde (molar ratio of 4-vinylaniline: 4-vinylbenzaldehyde: methyl acrylate 1:1:98) were weighed, and the organic gel softened and collapsed after irradiation with 365nm ultraviolet light for 5 min.

[0052] For example, the preparation of a solid organic gel: 20% methyl acrylate, 0.6% 1,4-butanediol diacrylate, 0.5% diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide, 4-vinylaniline and 4-vinylbenzaldehyde (molar ratio of 4-vinylaniline: 4-vinylbenzaldehyde: methyl acrylate 1:1:8) were weighed. The organic gel could not swell effectively after being exposed to ultraviolet light for 60 min.

[0053] For example, the preparation of solid organic gel: 20% by mass of methyl acrylate, 1% of 1,4-butanediol diacrylate, 0.2% of diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide, 4-vinylaniline and 4-vinylbenzaldehyde (molar ratio of 4-vinylaniline:4-vinylbenzaldehyde:methyl acrylate 1:1:98) were weighed, and the organic gel was strong and tough after being irradiated with ultraviolet light for 60 min.

[0054] For example, the preparation of solid organic gel: weigh 20% by mass of methyl acrylate, 0.6% of 1,4-butanediol diacrylate, 0.2% of diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide, 4-vinylaniline and 4-vinylbenzaldehyde (molar ratio of 4-vinylaniline: 4-vinylbenzaldehyde: methyl acrylate 1:1:98), and irradiate with ultraviolet light for 60 min.

[0055] In one possible implementation, the mass fraction of methyl acrylate in the prepolymer solution is 20%; the molar ratio of 4-vinylaniline, 4-vinylbenzaldehyde and methyl acrylate is (1:1:98) to (1:1:8); the mass fraction of 1,4-butanediol diacrylate in the prepolymer solution is 0.6%; and the mass fraction of diphenylphosphine oxide in the prepolymer solution is 0.2%.

[0056] In one possible implementation, the wavelength of ultraviolet light irradiation is 365 nm, and the duration of ultraviolet light irradiation is 1 min to 90 min.

[0057] For example, in a reaction vessel, anhydrous DMSO solvent is added, and the following are dissolved sequentially: methyl acrylate (MA), making it 20% of the total mass of the solution; 4-vinylaniline (VA) and 4-vinylbenzaldehyde (VB), calculated and weighed according to the molar ratio of n(VA):n(VB):n(MA) = 1:1:98; crosslinking agent 1,4-butanediol diacrylate (BDA), making it 0.6% of the total mass of the solution; the above mixed solution is sonicated until all monomers are fully dissolved, and the entire process is carried out in the dark; initiator diphenyl (2,4,6-trimethylbenzoyl)phosphorus oxide (TPO) is added, making it 0.2% of the total mass of the solution, and stirred to dissolve to obtain a homogeneous and transparent prepolymer solution; the prepolymer solution is poured into a mold and irradiated under a 365 nm wavelength ultraviolet lamp for 60 minutes. After irradiation, a solid organic gel is obtained; the solid organic gel is immersed in an excess of DMSO solution to wash away unreacted monomers and allow the gel network to fully swell, resulting in a purified organic gel.

[0058] In one possible implementation, the multifunctional active ingredient of traditional Chinese medicine is at least one of berberine hydrochloride, quercetin, luteolin, rhein, resveratrol, magnolol, curcumin, and derivatives of each ingredient, and the mass fraction of the multifunctional active ingredient of traditional Chinese medicine in the dimethyl sulfoxide drug mixture is 0.1% to 2%.

[0059] It should be noted that the preparation of microenvironment-adaptive cell cluster hydrophobic hydrogel is as follows: 0.1% to 2% of berberine hydrochloride by mass is dissolved in dimethyl sulfoxide to obtain a drug mixture; the organic gel is immersed in the drug mixture for 6 to 48 hours, and then transferred to excess deionized water for 24 to 72 hours to obtain the microenvironment-adaptive cell cluster hydrophobic hydrogel.

[0060] It should be noted that the drug loading rates of the organic gel impregnated in drug mixtures with mass fractions of 1% and 2%, and after 24 hours and 48 hours of impregnation, showed little difference. Furthermore, a significant amount of organic solvent remained after 24 hours of immersion in deionized water, while excessive drug loss occurred after 72 hours. Considering the cost of the hydrophobic hydrogel, the residual organic solvent rate, and the drug loading rate, the optimal choice for preparing the microenvironment-adaptive cell population hydrophobic hydrogel was a 1% drug mixture, with the organic gel impregnated in the drug mixture for 24 hours and then in deionized water for 48 hours. The preparation of the blank hydrophobic hydrogel did not involve the drug impregnation step. Cross-sectional laser microscope images of the blank hydrophobic hydrogel (MVV) and the drug-loaded cell population hydrophobic hydrogel, i.e., the microenvironment-adaptive cell population hydrophobic hydrogel (Ber@MVV), are shown below. Figure 1 It can be observed that both MVV and Ber@MVV are composed of abundant and dense cell-like structures, which also proves that the drug loading does not affect their structure.

[0061] For example, the purified organic gel was immersed in a DMSO drug mixture containing multifunctional active ingredients of traditional Chinese medicine for 24 hours. A 1% (w / w) berberine hydrochloride DMSO solution was prepared (i.e., 1g of drug dissolved in 99g of DMSO). The purified organic gel was immersed in this drug solution and allowed to stand at room temperature for 24 hours to allow the drug molecules to fully diffuse and load into the gel network. The gel was then removed to obtain the drug-loaded organic gel.

[0062] It should be noted that the prepared microenvironment-adaptive hydrophobic hydrogel is directly applied to the biofilm-infected wound after debridement. In the early stages of wound healing, the gel provides a moist environment and slowly releases the drug to maintain a baseline concentration. When bacteria multiply and form a biofilm, creating an acidic microenvironment, the gel detects the pH drop, breaks the Schiff base bonds, and initiates a "burst" drug release mode to precisely target the pathogens. The drug (berberine hydrochloride) exerts a comprehensive effect of antibacterial, anti-inflammatory, antioxidant, angiogenesis-promoting, and epithelialization-promoting effects, breaking the vicious cycle of infection-inflammation and promoting efficient wound healing. Due to its excellent water retention and long-lasting drug release capability, the frequency of dressing changes can be reduced, alleviating patient suffering.

[0063] Example 1 The density of the cell membrane structure is a necessary condition for the gel network to achieve good water absorption and swelling. Therefore, the water absorption and swelling behavior of hydrophobic hydrogels was evaluated by recording the mass change of the hydrogel in phosphate buffer over time. Simply put, the initial mass of the organic gel was recorded beforehand. Then, the organic gel was immersed in excess phosphate buffer and incubated in a 37°C shaker. At specified time points, the gel was removed, excess buffer was gently wiped off, and the weight was recorded. The swelling ratio was calculated using the following formula: Swelling ratio = Weight at time interval / Initial weight × 100%. The swelling curve was referenced from... Figure 2 The results showed that the gel group without BDA rapidly dehydrated during solvent displacement, failing to support its hydrophobic network structure. Conversely, as the BDA content reached 0.6%, the swelling ratio of its gel was significantly stronger than that of other gel groups.

[0064] Example 2 In vitro water retention study of cell-population-like hydrophobic hydrogels: The room-temperature water retention capacity of hydrophobic hydrogels was evaluated using a specific gravity method. In short, the drug-loaded organic gel was first impregnated with deionized water for 48 hours to fully swell. Then, excess surface moisture was wiped off, and the initial mass of the hydrophobic hydrogel was recorded. Next, the gel was placed in a well-ventilated environment at room temperature, and the remaining weight of the gel was measured and recorded at specified time points. The water retention rate was calculated using the following formula: Water retention rate = Weight at specified time points / Initial weight × 100%. The gel water loss curve was referenced... Figure 3The results showed that both MVV gel and Ber@MVV gel exhibited similar dehydration characteristics, retaining a certain amount of moisture even after standing for 5 days, demonstrating the excellent water retention properties of hydrophobic hydrogels. Under the same conditions, conventional hydrophilic hydrogels (carboxymethyl chitosan / oxidized hyaluronic acid, CMC / OHA) were completely dehydrated after air drying for 48 hours.

[0065] Example 3 For in vitro drug release from microenvironment-adaptive hydrophobic hydrogels: First, a standard concentration curve equation for berberine hydrochloride was established. Then, the hydrophobic hydrogel (QL@MAB) was placed in phosphate buffer (pH 7.4 or pH 5.5) to investigate the in vitro drug release behavior. The drug was immersed in 50 mL centrifuge tubes and placed in a 37°C constant-temperature shaker. 2 mL of the released solution was taken at fixed points to measure the released drug, and 2 mL of fresh released solution was added simultaneously. The absorbance value was measured using a UV spectrophotometer. The percentage of drug release was determined according to the standard curve. Figure 4 A. Quercetin releases more than twice the amount released after 24 hours under stimulation at pH 5.5 compared to incubation at pH 7.4. Figure 4 B. With prolonged time, the microenvironment-adaptive cell cluster hydrophobic hydrogel exhibited a quercetin release cycle of up to 15 days, indicating that the microenvironment-adaptive cell cluster hydrophobic hydrogel has the purpose of self-regulating drug release and continuous drug delivery.

[0066] Example 4 Reference Figure 5 A. Research on the self-regulation mechanism of microenvironment-adaptive cell population hydrophobic hydrogels: First, microenvironment-adaptive cell population hydrophobic hydrogels (Ber@MVV) were immersed in phosphate buffer at pH 7.4 or pH 5.5 and incubated in a 37°C constant temperature shaker for 3 days. The three-dimensional morphology of the hydrogel surface was scanned using a 3D ultra-depth-of-field microscope. The 3D ultra-depth-of-field images showed that the surface of the MVV gel at pH 7.4 was rough and heterogeneous, similar to the surface of a cell membrane. However, once transferred to phosphate buffer at pH 5.5, the surface became even more irregular. This indicates that the Schiff bases of the gel molecular chains underwent a breakage reaction after being stimulated by a slightly acidic environment, constructing material transport channels of varying sizes, thus making the surface increasingly rough. Figure 5 B's quantitative statistics on average roughness also prove this point.

[0067] Example 5 Reference Figure 6This study investigated the in vitro antibacterial activity of hydrophobic hydrogels with microenvironment-adaptive cell populations. First, Staphylococcus aureus and Escherichia coli strains, frozen in glycerol tubes, were gradually acclimatized to room temperature. Then, they were incubated overnight in LB broth at 37°C and 220 rpm. Once the bacterial suspension became turbid, bacterial viability was evaluated using a microplate reader to ensure bacterial recovery and reproduction. Next, the inhibition zone method was used to evaluate the antibacterial activity of the four gels. Specifically, a bacterial suspension (1×10⁶ CFU / mL, 100 μL) was spread evenly on an LB agar plate, and the gel was dispersed on the plate and incubated at 37°C. Measurements were taken on days 1, 4, 7, and 10, and the diameter of the inhibition zone was recorded using ImageJ software. To assess biofilm removal efficiency, 200 μL of bacterial suspension was transferred to a 96-well plate, and the gel was added for co-incubation for 12 hours. After incubation, the biofilm was washed and quantitatively evaluated using crystal violet staining. Actual image of the antibacterial ring Figure 6 As shown in Figure A, the gels on the left and right represent the blank hydrophobic hydrogel group (MVV) and the drug-loaded hydrophobic hydrogel group, namely the microenvironment-adaptive cell population hydrophobic hydrogel (Ber@MVV), respectively. The curves showing the change in the diameter of the inhibition zone are shown in Figure A. Figure 6 B inhibits the diameter statistics of E. coli and Figure 6 The C-curing diameter statistic of Staphylococcus aureus showed that the Ber@MVV group had a long-term inhibitory effect on the growth and migration of both Staphylococcus aureus and Escherichia coli; the evaluation of anti-biofilm ability can be found in [reference needed]. Figure 6 The results showed that Ber@MVV has a remarkable ability to remove S. aureus biofilms, and also has a certain ability to remove E. coli biofilms.

[0068] Example 6 Reference Figure 7 In vitro ROS scavenging study of microenvironment-adaptive hydrophobic hydrogels: 2 × 10⁵ HUVECs cells were seeded in 24-well plates and cultured overnight in a 5% CO₂ incubator. Then, DMEM medium containing 100 ng / mL lipopolysaccharide (LPS) was added for further culture. The group without LPS stimulation was designated as the Control (-) group. Simultaneously, transwell chambers were placed in the medium, and both the blank hydrophobic hydrogel group (MVV) and the drug-loaded hydrophobic hydrogel group (Ber@MVV) were added and co-cultured for 4 hours. The cells were stained with DCFH-DA for 30 min, and finally, the results were observed and statistically analyzed using a fluorescence microscope. ROS scavenging experimental figures are shown below. Figure 7 A, and ROS quantitative statistics are shown in Figure 7 B. The results showed that the microenvironment-adaptive cell population hydrophobic hydrogel (Ber@MVV) prepared in this application has significant ROS scavenging activity.

[0069] Example 7 Reference Figure 8 To investigate the therapeutic effect of microenvironment-adaptive hydrophobic hydrogels on biofilm-infected wounds: A biofilm-infected wound model was constructed: Rats were anesthetized with 2 ml / kg sodium pentobarbital via intraperitoneal injection; after anesthesia, the rats' backs were used as the modeling area, and hair was removed; the skin in the modeling area was completely excised with surgical scissors, with a diameter of 8 mm, reaching the subcutaneous layer without damaging the muscle layer; steel rings were sutured around the wound using 2-0 surgical sutures; and the wound was bandaged with bandages and gauze to create a diabetic full-thickness defect infection model; Rats were randomly divided into 4 groups of 6 rats each. After establishing the diabetic model, the rats were randomly divided into an untreated group (Control), a commercial dressing treatment group (Tegaderm), a blank hydrophobic hydrogel group (MVV), and a berberine hydrochloride-loaded hydrophobic hydrogel group (Ber@MVV); (Refer to...) Figure 8 AC, the gel was changed in each group on days 3, 7, 10, and 12, and representative images of wound healing were taken. The wound area was analyzed using ImageJ analysis software (n=6). The wound healing rate was calculated as follows: Healing rate = (Initial wound area - Wound area at the specified time interval) / Initial wound area × 100%; Comparison of wound healing: as shown... Figure 8 As shown in Figure A, the berberine hydrochloride-loaded hydrophobic hydrogel group, also known as the microenvironment-adaptive cell-like hydrophobic hydrogel (Ber@MVV), significantly accelerated the healing of hair-covered wounds after 12 days of treatment, while unhealed wounds were still visible in other groups. To better visualize the wound healing rate of each group, Figure 8 B depicts the trajectory of the healing area at each time point. Figure 8 C plotted the corresponding healing curves. After 12 days of treatment, wound healing was delayed in the untreated group and the blank hydrophobic hydrogel group (MVV). In contrast, the wound healing rate of the Ber@MVV group was significantly improved. This indicates that Ber@MVV can significantly improve the healing efficiency of biofilm-infected wounds, and its effect is superior to other groups, making it an ideal dressing for promoting the healing of biofilm-infected wounds.

[0070] Example 8 Reference Figure 9This study investigated the sustained antibacterial activity of microenvironment-adaptive hydrophobic hydrogels on wounds. The survival rate of Staphylococcus aureus in rat wounds treated with different dressings was determined using the plating method. Specifically, on postoperative days 3, 7, and 10, the skin and subcutaneous tissue around the wound were gently wiped with cotton swabs to extract bacteria. The swabs were then immersed in LB broth and incubated at 37°C for 7 hours. The incubated bacterial extract was then spread onto LB agar plates and incubated upside down at 37°C for 24 hours. Representative photographs of the bacterial plating culture were taken, and bacterial growth was assessed by colony counting. Gram staining was used for section analysis. See the image of the bacterial plating. Figure 9 A, Statistical analysis of antibacterial rates during different wound healing processes is shown in [reference]. Figure 9 B, See Gram staining image. Figure 9 C; The results showed that the microenvironment-adaptive cell population hydrophobic hydrogel (Ber@MVV) provided in this application has significant sustained in vivo antibacterial activity.

[0071] Chronic wound infections, especially refractory wounds with biofilm formation, pose a significant challenge in clinical treatment. The presence of biofilms not only hinders immune cells from clearing pathogens but also enhances bacterial resistance, leading to a prolonged inflammatory state and delaying the healing process. Currently, commonly used clinical treatments include dressing changes, mechanical debridement, negative pressure drainage, and topical antibiotics. However, these methods generally suffer from uncontrollable drug release, poor responsiveness to the microenvironment, and a tendency to develop drug resistance and recurrent infections. Hydrogel materials, due to their high water content, good biocompatibility, and certain drug loading capacity, are widely used in wound dressings. However, traditional hydrophilic hydrogels still have significant limitations in practical applications: firstly, they have low drug loading rates and are prone to burst release under non-stimulating conditions, resulting in low drug utilization efficiency; secondly, they lack intelligent responsiveness to the wound microenvironment (such as pH, enzymes, and reactive oxygen species), failing to achieve on-demand drug release; and thirdly, some responsive gels degrade after drug release, potentially triggering local inflammatory reactions and interfering with the healing process. In recent years, researchers have attempted to improve the properties of hydrogels by introducing stimulus-responsive groups or biomimetic structures. For example, some studies have utilized pH-sensitive bonds (such as Schiff base bonds) to achieve drug release in acidic environments, or enhanced the biocompatibility of materials with the biological environment by mimicking cell membrane structures. However, these strategies still face challenges such as complex fabrication processes, high costs, poor drug loading stability, and limited biomimetic functions. In particular, in simulating the "recognition-response" intelligent behavior of immune cells, a material system that can simultaneously achieve structural biomimicry, functional synergy, and fabrication feasibility has yet to emerge.

[0072] Based on this, this application provides a method for preparing a microenvironment-adaptive, cell-population-like hydrophobic hydrogel, which possesses microenvironment-adaptive capabilities, can mimic the behavior of immune cell populations, and achieves long-lasting moisturizing and intelligent drug release. By employing a hydrophobic monomer system including methyl acrylate, 4-vinylaniline, and 4-vinylbenzaldehyde, and performing UV-initiated polymerization in DMSO, a stable organic gel network is formed. This network undergoes phase separation during subsequent solvent displacement, forming a dense, cell-membrane-like structure that effectively encapsulates drugs (such as berberine hydrochloride), preventing premature release under non-irritating conditions. In a slightly acidic wound environment (pH 4.5-6.5), Schiff base bonds break, forming drug release channels for on-demand drug release. During polymerization, 4-vinylaniline and 4-vinylbenzaldehyde form dynamic Schiff base bonds, which are stable under neutral conditions. Hydrolysis under acidic conditions endows the hydrogel with pH-responsive properties, enabling it to mimic the recognition-response behavior of immune cell membranes and automatically initiate drug release in the slightly acidic environment of biofilm infection. Using dimethyl sulfoxide (DMSO) as a co-solvent ensures the dissolution of hydrophobic monomers and active ingredients of traditional Chinese medicine, and subsequent water replacement induces the assembly of hydrophobic segments to form cell-like structures, significantly improving drug encapsulation efficiency and storage stability. Experiments show that this hydrogel can achieve drug sustained release for up to 15 days. The entire preparation process is based on common free radical polymerization and physical impregnation methods, requiring no complex modification or expensive equipment, and is suitable for large-scale production. By adjusting the monomer ratio, crosslinking agent, and initiator dosage, the mechanical properties, swelling behavior, and drug release kinetics of the gel can be flexibly adjusted. The loaded multifunctional traditional Chinese medicine components (such as berberine hydrochloride) have multiple effects such as antibacterial, anti-inflammatory, antioxidant, and angiogenesis-promoting properties, which synergistically enhance the therapeutic effect on biofilm-infected wounds. In other words, the preparation method of this application not only overcomes the shortcomings of existing hydrogel dressings in terms of controlled drug release, microenvironment responsiveness, and structural biomimicry, but also achieves the controllable preparation of high-performance cell-like hydrophobic hydrogels through a simple process.

[0073] In the description of the embodiments of this application, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first," "second," "third," or "fourth" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0074] In the description of the embodiments of this application, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0075] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A microenvironment-adaptive cell-population-like hydrophobic hydrogel, characterized in that, The microenvironment-adaptive cell cluster hydrophobic hydrogel was prepared by initiating polymerization of methyl acrylate, 4-vinylaniline, 4-vinylbenzaldehyde, crosslinking agent and initiator, and loaded with multifunctional active ingredients of traditional Chinese medicine.

2. The microenvironment-adaptive cell-population-like hydrophobic hydrogel according to claim 1, characterized in that, The methyl acrylate, 4-vinylaniline, and 4-vinylbenzaldehyde are uniformly dispersed and dissolved in dimethyl sulfoxide to form a prepolymer solution. A crosslinking agent and an initiator are added to the prepolymer solution to initiate a polymerization reaction and form a solid organic gel. The solid organic gel is placed in excess dimethyl sulfoxide and washed and swollen to form a purified organic gel. The purified organic gel is loaded with multifunctional traditional Chinese medicine active ingredients to form a drug-loaded organic gel. The drug-loaded organic gel is immersed in deionized water to perform solvent replacement, inducing phase separation and swelling of the hydrophobic polymer network to form a microenvironment-adaptive cell-like hydrophobic hydrogel.

3. The microenvironment-adaptive cell-population-like hydrophobic hydrogel according to claim 2, characterized in that, The methyl acrylate has a mass fraction of 15% to 25% in the prepolymer solution; the molar ratio of 4-vinylaniline to 4-vinylbenzaldehyde is 1:1; and the molar ratio of 4-vinylaniline, 4-vinylbenzaldehyde, and methyl acrylate is (1:1:98) to (1:1:8). The crosslinking agent is 1,4-butanediol diacrylate, and the mass fraction of 1,4-butanediol diacrylate in the prepolymer solution is 0% to 1%. The initiator is diphenylphosphine oxide, and the mass fraction of the initiator in the prepolymer solution is 0.05% to 0.5%.

4. The microenvironment-adaptive cell-population-like hydrophobic hydrogel according to claim 1, characterized in that, The multifunctional active ingredient of the traditional Chinese medicine is at least one of berberine hydrochloride, quercetin, luteolin, rhein, resveratrol, magnolol, curcumin, and derivatives of each ingredient.

5. The microenvironment-adaptive cell-population hydrophobic hydrogel according to any one of claims 1 or 4, characterized in that, The mass fraction of the multifunctional active ingredient in the traditional Chinese medicine is 0.1% to 2%.

6. The microenvironment-adaptive cell-population-like hydrophobic hydrogel according to claim 2, characterized in that, The volume ratio of the drug-loaded organic gel to the deionized water is 1:(50-100), the drug-loaded organic gel is soaked in excess deionized water for 24-72 hours, and the drug-loaded organic gel is left to stand in excess deionized water at room temperature.

7. A method for preparing a microenvironment-adaptive cell-population-like hydrophobic hydrogel as described in any one of claims 1 to 6, characterized in that, A method for preparing a microenvironment-adaptive cell population-like hydrophobic hydrogel, comprising the following steps: Preparation of the organic gel: The organic gel was prepared by free radical polymerization initiated by ultraviolet light. Methyl acrylate, 4-vinylaniline, 4-vinylbenzaldehyde and 1,4-butanediol diacrylate were weighed according to the formula ratio and dissolved in dimethyl sulfoxide to form a mixed solution. The mixed solution was ultrasonically treated until fully dissolved and then protected from light. Diphenylphosphine oxide was weighed according to the formula ratio and added to the mixed solution and dissolved to obtain a homogeneous and transparent prepolymer solution. The prepolymer solution was subjected to an initiation polymerization reaction under ultraviolet light to form a solid organic gel. The solid organic gel was immersed in excess dimethyl sulfoxide to elute unreacted monomers and allow the gel to fully swell and reach equilibrium to obtain the purified organic gel. Preparation of cell cluster hydrophobic hydrogel: Step 1, 4-vinylaniline, 4-vinylbenzaldehyde, methyl acrylate (15%–25% by mass), 1,4-butanediol diacrylate (0%–1% by mass), and diphenylphosphine oxide (0.05%–0.5% by mass) are dissolved in dimethyl sulfoxide to form a prepolymer solution. The molar ratio of 4-vinylaniline, 4-vinylbenzaldehyde, and methyl acrylate is (1:1:98) to (1:1:8). The prepolymer solution is subjected to an initiation polymerization reaction under ultraviolet light to form a solid organic gel. The solid organic gel is then immersed in a dimethyl sulfoxide drug mixture containing multifunctional traditional Chinese medicine active ingredients for 6 to 48 hours to obtain a drug-loaded organic gel. Step 2: The drug-loaded organic gel is immersed in excess deionized water at room temperature for 24h to 72h, with the volume ratio of the drug-loaded organic gel to the deionized water being 1:(50 to 100), to obtain a microenvironment-adaptive cell population hydrophobic hydrogel.

8. The method for preparing the microenvironment-adaptive cell population hydrophobic hydrogel according to claim 7, characterized in that, The molar ratio of 4-vinylaniline to 4-vinylbenzaldehyde is 1:

1.

9. The method for preparing the microenvironment-adaptive cell population hydrophobic hydrogel according to claim 7, characterized in that, The multifunctional active ingredient of the traditional Chinese medicine is at least one of berberine hydrochloride, quercetin, luteolin, rhein, resveratrol, magnolol, curcumin, and derivatives of each ingredient, and the mass fraction of the multifunctional active ingredient of the traditional Chinese medicine in the dimethyl sulfoxide drug mixture is 0.1% to 2%.

10. An application of a microenvironment-adaptive cell-population-like hydrophobic hydrogel as described in any one of claims 1 to 6, characterized in that: Microenvironment-adaptive cell-group hydrophobic hydrogels are used in the preparation of wound dressings.

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