Multifunctional integrated hydrogels, methods of making and using the same

Abstract

A multifunctional integrated hydrogel, its preparation method, and its applications are disclosed. The hydrogel base system is constructed using gelatin and sodium alginate, natural polymers with excellent biocompatibility. Molecular structure modification enhances tissue adhesion. Phenylboronic acid-modified gelatin retains gelatin's good biocompatibility and cell affinity while also providing dynamic covalent cross-linking capabilities through phenylboronic acid groups. Oxidized sodium alginate, while maintaining its inherent biosafety, reduces its molecular weight through oxidation, improving degradation performance. Simultaneously, the aldehyde groups on its molecular chain serve as efficient cross-linking sites. PBA-Gel and OSA react with Schiff bases via dynamic borate ester bonds to form a double-network hydrogel. This system exhibits excellent injectability, self-healing properties, and strong wet adhesion to biological tissues. This hydrogel can be precisely delivered to pleural rupture sites via a minimally invasive catheter, rapidly gelling and tightly adhering to irregular wound surfaces. Its strong tissue adhesion resists intrathoracic pressure fluctuations and fluid erosion caused by respiratory movements, solving the problems of easy detachment and incomplete sealing associated with traditional occlusive agents.

Description

Technical Field

[0001] This invention relates to the field of biomaterials technology, specifically to a multifunctional integrated hydrogel, its preparation method, and its applications. Background Technology

[0002] Pneumothorax is a common clinical condition, referring to the abnormal accumulation of gas in the pleural cavity, resulting in pneumothorax. Intercostal drainage is a common treatment to restore negative pressure in the pleural cavity; however, pleural ruptures are difficult to heal spontaneously, making it a common and recurring thorny problem in clinical practice.

[0003] Over the past three decades, medical professionals both domestically and internationally have employed various methods to temporarily seal leaking wounds, stopping air leakage and promoting healing of pleural fistulas at the site of lung injuries. However, existing sealing agents generally suffer from weak tissue adhesion and are susceptible to detachment due to respiratory movements, changes in intrathoracic pressure, and fluid flushing. Occlusive devices, on the other hand, are costly and may induce granulation tissue growth or displacement. Therefore, the development of a sealing material that combines adhesive stability, compatibility, and biocompatibility without affecting normal physiological functions is urgently needed in clinical practice. This ideal sealing material should be able to adapt to the irregular shape of pleural tears, achieving complete wound coverage without leaving gaps that could lead to air leakage; it should have a suitable gelation rate and adhesiveness, enabling both minimally invasive catheter delivery and rapid, long-lasting adhesion to the wound site; and it should possess good biocompatibility, be loaded with antibacterial, anti-inflammatory, and repair-promoting active ingredients to accelerate pleural tear repair and prevent infection. Most existing adhesive hydrogels have limited functionality and cannot simultaneously meet multiple requirements such as strong adhesion, efficient antibacterial and anti-inflammatory effects, and injectable self-repair capabilities, thus limiting their application in complex clinical scenarios such as pneumothorax closure. Summary of the Invention

[0004] To address the clinical needs and limitations of existing materials, this invention provides a multifunctional integrated hydrogel, its preparation method, and its application. It can quickly form a gel and adhere closely to irregular wound surfaces. Its strong tissue adhesion can resist thoracic pressure fluctuations and fluid erosion caused by respiratory movements, solving the problems of easy detachment and incomplete sealing of traditional sealing agents.

[0005] The technical solution adopted in this invention is: a multifunctional integrated hydrogel, wherein the multifunctional integrated hydrogel is a double-network hydrogel formed by the reaction of PBA-Gel and OSA with Schiff base through dynamic borate ester bonds, supporting 2,3,4-trihydroxybenzaldehyde (THB) and Zn. 2+ Self-assembly to form metal-flavonoid nanoparticles (THB / Zn²) + NPs).

[0006] The metal-flavonoid nanoparticles (THB / Zn²) +NPs embed nanoparticles into a dual-network hydrogel through hydrogen bonding and electrostatic interactions.

[0007] The 2,3,4-trihydroxybenzaldehyde (THB) mentioned above is a flavonoid phenolic metabolite extracted from Anoectochilus roxburghii.

[0008] The volume ratio of PBA-Gel to OSA is 1:3 to 3:1.

[0009] The volume ratio of PBA-Gel to OSA is 1:1.

[0010] The 2,3,4-trihydroxybenzaldehyde (THB) and Zn 2+ The mass ratio is 1:0.5-1:2.

[0011] The 2,3,4-trihydroxybenzaldehyde (THB) and Zn 2+ The mass ratio is 1:0.8-1:1.5.

[0012] The multifunctional integrated hydrogel contains metal-flavonoid nanoparticles (THB / Zn²). + The content of NPs is 0.01-0.1 wt%.

[0013] A method for preparing the aforementioned multifunctional integrated hydrogel includes the following steps:

[0014] Step 1: Construction of the gelatin and sodium alginate hydrogel base system: Vortex mix phenylboronic acid modified gelatin (PBA-Gel) aqueous solution and oxidized sodium alginate (OSA) aqueous solution for 20-40 s, let stand at room temperature for 20-40 min, and crosslink to form a PBA-Gel / OSA base hydrogel with strong tissue adhesion. Step 2: Preparation of metal nanoparticles: The flavonoid compound THB is reacted with the metal ion Zn. 2+ When added together to PBS buffer solution, self-assembly yields metal-flavonoid nanoparticles (THB / Zn²⁺). + NPs); Step 3: Preparation of hydrogel loaded with metal nanoparticles: The prepared metal nanoparticles were added to the PBA-Gel / OSA basic hydrogel system, vortexed for 10 s, and allowed to stand at room temperature for 30 min. The nanoparticles were embedded into the gel network through hydrogen bonding and electrostatic interaction to obtain an adhesive hydrogel with high bioactivity.

[0015] In step 1, the concentration of phenylboronic acid modified gelatin (PBA-Gel) is 10-40 wt% in aqueous solution, and the concentration of sodium oxidized alginate (OSA) aqueous solution is 8-25 wt%.

[0016] The application of the aforementioned multifunctional integrated hydrogel in the preparation of a biodegradable medical occlusion agent for the treatment of pneumothorax.

[0017] The beneficial effects of this invention are as follows: This invention provides a multifunctional integrated hydrogel, its preparation method, and its application. It utilizes gelatin and sodium alginate, natural polymers with excellent biocompatibility, to construct a hydrogel basic system, enhancing tissue adhesion through molecular structure modification. Phenylboronic acid-modified gelatin (PBA-Gel) retains the good biocompatibility and cell affinity of gelatin while also endowing the material with dynamic covalent cross-linking capabilities through phenylboronic acid groups. Oxidized sodium alginate (OSA), while maintaining the inherent biosafety of sodium alginate, reduces its molecular weight through oxidative modification, improving the material's degradation performance. Simultaneously, the aldehyde groups on its molecular chain can serve as highly efficient cross-linking sites. PBA-Gel and OSA react with Schiff bases through dynamic borate ester bonds to form a double-network hydrogel. This system exhibits excellent injectability, self-healing properties, and strong wet adhesion to biological tissues. This hydrogel can be precisely delivered to the pleural rupture site using a minimally invasive catheter, quickly forming a gel and closely adhering to the irregular wound surface. Its strong tissue adhesion can resist the fluctuations in pleural pressure and the flushing of body fluids caused by respiratory movements, solving the problems of easy detachment and incomplete sealing of traditional sealing agents. The core innovation of this invention lies in: 1. Construction of a dual dynamic cross-linking network: Dynamic borate ester bonds are formed between the phenylboronic acid groups on PBA-Gel and the cis-diol structure on the OSA chain, while dynamic Schiff base bonds are formed between the amino groups on PBA-Gel and the aldehyde groups on OSA. These two dynamic covalent bonds synergistically construct the self-healing framework of the hydrogel and provide a basis for multiple interactions with various functional groups (such as hydroxyl and amino groups) on the tissue surface, thereby achieving strong wet tissue adhesion. 2. Synergistic Functional Design: THB / Zn² + The introduction of NPs gives the hydrogel both the anti-inflammatory and antioxidant activities of THB and Zn²⁺. + The antibacterial properties are enhanced, and the nanoparticles are embedded in the gel network through hydrogen bonds and electrostatic interactions, avoiding the burst release of small molecule drugs and achieving long-term sustained release and synergistic treatment. 3. Mild and controllable preparation process: The entire preparation process requires no additional cross-linking agents, avoiding potential toxicity. The reaction conditions are room temperature and physiological pH range, enabling mild loading of cells and active ingredients. The degradation products are gelatin peptides, sodium alginate oligosaccharides, THB derivatives, and Zn²⁺. + It exhibits excellent biocompatibility and shows no significant cytotoxicity.

[0018] The beneficial effects of the composite hydrogel obtained by this invention are as follows: (1) Excellent injectability: The viscosity of the gel precursor is 50-500 mPa. Within the range of s, it can be smoothly extruded through a 21-27 G minimally invasive catheter, forming gel in situ at the treatment site, adapting to the clinical needs of complex morphologies such as pneumothorax and wounds, with minimal trauma and convenient operation; (2) Excellent adhesion performance: The tensile peel strength of the adhesive to moist biological tissues (such as skin and pleura) is greater than that of the currently used clinical sealing agents. The storage modulus after gelation is 1000-5000 Pa, which can match the mechanical environment of the tissue around the pleural fistula. It can resist the flushing of body fluid and the traction of tissue activity, and achieve firm adhesion and air leakage sealing. (3) Significant antibacterial and anti-inflammatory activity: The inhibition rate against Escherichia coli and Staphylococcus aureus is ≥90%, and it can significantly scavenge reactive oxygen species (ROS), downregulate the expression of inflammatory factors, and inhibit infection; (4) Excellent biocompatibility: The survival rate of L929 fibroblasts and human lung epithelial cells is ≥85%, which can promote cell adhesion and spreading. The degradation products are non-toxic and have high biocompatibility. (5) Wide range of applications: It is biodegradable, requires no secondary surgery, and is suitable for clinical scenarios such as pneumothorax leak sealing, skin wound repair, visceral tissue adhesion, and drug delivery carrier. It has extremely high medical value and market potential. Attached Figure Description

[0019] Figure 1 Different THB / Zn² + Macroscopic morphology of composite hydrogels with NP loading. (a) PBA-Gel / OSA basic hydrogel; (bd) Composite hydrogels with NP loading of 0.01 wt%, 0.05 wt%, and 0.10 wt%, respectively.

[0020] Figure 2 Tissue adhesion properties of composite hydrogels. (a) Adhesion state of hydrogels on the surface of fresh pig lungs; (b) Schematic diagram of pig skin overlap shear adhesion strength test; (cd) Comparison of adhesion strength of base hydrogel and hydrogels with different NPs loading.

[0021] Figure 3 Cell compatibility of composite hydrogels (CCK-8 assay). Effects of (ab) on L929 cell survival; Effects of (cd) on BEAS-2B cell survival.

[0022] Figure 4 ROS scavenging ability of composite hydrogels (DCFH-DA fluorescent probe method). The control groups included: normal cells (nc), LPS-stimulated group, hydrogel group loaded with 0.05 wt% NPs, herbal extract (THB) group, and free NPs group.

[0023] Figure 5Antimicrobial properties of the composite hydrogel (plate count method). (a) Antimicrobial effect against Escherichia coli; (b) Antimicrobial effect against Staphylococcus aureus. The results show that at a loading of 0.05 wt%, the inhibition rate against Escherichia coli is ≥92%, and the inhibition rate against Staphylococcus aureus is ≥95%. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0025] To ensure the feasibility of the invention and the reasonableness of its scope of protection, the following ranges are defined for each component and key performance parameter: Raw material specifications: Gelatin: with a molecular weight range of 50,000-150,000 Da, preferably 80,000-120,000 Da, using one or more combinations of bovine bone gelatin, pigskin gelatin or fish skin gelatin, and a gel strength of 150-300 Bloom.

[0026] Sodium alginate: molecular weight range of 100,000-300,000 Da, preferably 150,000-250,000 Da, guluronic acid (G) content of 40%-70%, preferably 50%-60%.

[0027] 3-Aminophenylboronic acid: purity ≥98%, molecular weight 139.96 Da.

[0028] 1-Ethyl-(3-dimethylaminopropyl)carbodiimide (EDC) HCl: Purity ≥ 97%, molecular weight 191.70 Da.

[0029] N-hydroxysuccinimide (NHS): purity ≥98%, molecular weight 115.09 Da.

[0030] Sodium periodate (NaIO4): purity ≥99%, molecular weight 213.89 Da.

[0031] 2,3,4-Trihydroxybenzaldehyde (THB): Purity ≥98%, molecular weight 154.11 Da.

[0032] Zinc sulfate (ZnSO4) 7H2O): Purity ≥99%, molecular weight 287.55 Da.

[0033] Other reagents: Dimethyl sulfoxide (DMSO), anhydrous ethanol, phosphate buffered saline (PBS), etc., were all of analytical grade.

[0034] Hydrogel composition and process parameter range: Injectability-related viscosity: gel precursor at 25°C and shear rate of 10-100 s⁻¹ - ¹ Under these conditions, the viscosity range is 50-500 mPa·s, preferably 100-300 mPa·s, to ensure smooth injection through a 21-27 G minimally invasive catheter.

[0035] Elastic modulus suitable for pleural fistula: After the hydrogel is gelled (and allowed to stand at room temperature for 30 min), under the conditions of 1 Hz frequency and 1% strain, the storage modulus (G') is 1000-5000 Pa, preferably 1500-3000 Pa, which can adapt to the mechanical environment of the tissues around the pleural fistula and resist the deformation impact caused by respiratory movement.

[0036] Tissue adhesion strength: Using the overlap shear test method, the adhesion strength to moist biological tissues such as pigskin or peritoneum is ≥14 kPa (adhesion strength of existing commercial occluders).

[0037] Example 1: Preparation of PBA-Gel / OSA-based hydrogel (1) PBA-Gel synthesis: Prepare a mixed solvent of deionized water and DMSO at a volume ratio of 1:2-1:6, preferably 1:3-1:5; weigh 5-20 g of gelatin and add it to 100 mL of the mixed solvent, stir at 30-50℃ for 3-8 h until completely dissolved, preferably at 40-45℃ for 4-6 h; separately weigh 3-aminophenylboronic acid and EDC. HCl, NHS, wherein the molar ratio of 3-aminophenylboronic acid to the amino group in gelatin is 0.5:1-2:1, EDC The molar ratio of HCl to 3-aminophenylboronic acid was 1:1-1.5:1, and the molar ratio of NHS to 3-aminophenylboronic acid was 1:1-1.5:1. 30-80 mL of the mixed solvent was added, and the mixture was stirred at room temperature for 20-40 min, preferably 30 min, for activation. The activated solution was slowly added dropwise to the gelatin solution to adjust the pH to 4.5-6.5, preferably 5.0-5.5. The mixture was stirred at room temperature in the dark for 12-48 h, preferably 24-36 h. The reaction solution was transferred to a 500-2000 Da dialysis bag and dialyzed for 2-5 days, preferably 1000 Da dialysis bag for 3 days, with deionized water replaced every 8-12 h. After pre-freezing at -60℃ to -80℃ for 4-8 h, the mixture was freeze-dried for 12-36 h to obtain PBA-Gel sponges, which were then sealed and stored under cold storage. The grafting rate of the PBA-Gel modified sponges was measured using a molecular fluorescence spectrophotometer, as shown in Table 1.

[0038] Table 1. PBA-Gel grafting rate

[0039] (2) OSA preparation: Weigh 2-10 g of sodium alginate, add 20-100 mL of deionized water and 2-20 mL of anhydrous ethanol, the volume ratio of deionized water to anhydrous ethanol is 5:1-15:1, preferably 8:1-12:1; adjust pH to 5.0-7.0, preferably pH 5.5-6.5, stir at room temperature for 1-4 h to dissolve, preferably 2 h; add NaIO4 under dark conditions, the molar ratio of NaIO4 to uronic acid units in sodium alginate is 0.1:1-0.5:1, preferably 0.2:1-0.3:1, stir at room temperature under dark conditions for 2-6 h, preferably 4 h; add 0.5-2 mL of ethylene glycol to quench for 20-40 min, preferably 30 min; transfer the reaction solution to a 500-2000 Da dialysis bag for dialysis for 2-5 days, preferably 1000 Da dialysis bag for 3 days. After freeze-drying, OSA powder was obtained and stored in a sealed container. The oxidation degree of OSA was tested by titration, as shown in Table 2.

[0040] Table 2. Oxidation degree of OSA

[0041] (3) Preparation of the adhesive hydrogel matrix: Prepare 10-40 wt% PBA-Gel aqueous solution (dissolved by stirring at 50-70℃) and 8-25 wt% OSA aqueous solution (dissolved by stirring at room temperature), preferably 15-30 wt% PBA-Gel aqueous solution and 12-20 wt% OSA aqueous solution; measure PBA-Gel aqueous solution and OSA aqueous solution at a volume ratio of 1:3-3:1, preferably 1:2-2:1, more preferably 1:1; vortex mix for 20-40 s, and let stand at room temperature for 20-40 min to form a PBA-Gel / OSA basic hydrogel with strong tissue adhesion. By adjusting the concentration of PBA-Gel and OSA and the mixing volume ratio, the adhesive strength, gelation speed and mechanical properties of the hydrogel can be controlled. Table 3 shows the gelation time and adhesive strength of hydrogels with different PBA-Gel and OSA concentrations.

[0042] Table 3. Gel formation time and adhesion strength of PBA-Gel / OSA hydrogels with different concentrations

[0043] Example 2: Low load THB / Zn² + Preparation of composite hydrogels Step 1, Preparation of PBA-Gel / OSA basic hydrogel; (1) Preparation of PBA-Gel: Prepare a mixed solvent of deionized water and DMSO at a volume ratio of 1:5. Weigh 10 g of gelatin (molecular weight 120,000 Da, 240 Bloom) and add it to 100 mL of the mixed solvent. Stir at 45℃ for 6 h until completely dissolved. Separately weigh excess 3-aminophenylboronic acid (molar ratio of 3-aminophenylboronic acid to the amino group in gelatin is 1.5:1) and EDC. A mixed solution was prepared by mixing HCl (molar ratio of HCl to 3-aminophenylboronic acid 1.5:1) and NHS (molar ratio of NHS to 3-aminophenylboronic acid 1.5:1). 60 mL of the mixed solvent was added, and the mixture was stirred at room temperature for 30 min to activate the gelatin solution. The activated solution was then slowly added dropwise to a gelatin solution to adjust the pH to 5.5, and stirred at room temperature in the dark for 48 h. The reaction solution was transferred to a 1000 Da dialysis bag and dialyzed for 3 days. After pre-freezing at -80℃ for 6 h, the solution was freeze-dried for 24 h to obtain PBA-Gel sponges, which were then sealed and stored. The stirring time was 48 h, and the reaction pH was 5.5 to increase the grafting rate.

[0044] (2) Preparation of OSA: Same as in Example 1.

[0045] Step 2: React the flavonoid compound THB with the metal ion Zn²⁺ +Add THB to PBS buffer solution at a mass ratio of 1:0.5-1:2, preferably 1:0.8-1:1.5; wherein the concentration of THB in PBS buffer solution is 0.1-1.0 wt%, preferably 0.3-0.6 wt%; stir at room temperature for 2-6 h, preferably 3-4 h, to self-assemble a series of metal-flavonoid nanoparticles (THB / Zn²). + NPs) dispersion. Different nanoparticles have different antioxidant and antibacterial properties. Table 4 shows the ratio and properties of different nanoparticles.

[0046] Table 4. Combinations and properties of different metal-flavonoid nanoparticles

[0047] Step 3: Preparation of composite hydrogel: Prepare 30 wt% PBA-Gel aqueous solution and 20 wt% OSA aqueous solution, weigh 1 mL of the two solutions at a volume ratio of 1:1, and vortex mix for 30 s; add 20 μL of nanoparticle dispersion (THB and ZnSO4). The mass ratio of 7H2O is 1:0.5, which is 0.1g of THB and 0.22g of ZnSO4. Dissolve 7H2O in 10 mL PBS buffer, vortex for 10 s, and let stand at room temperature for 30 min to form a composite hydrogel.

[0048] Example 3: Medium Loading THB / Zn² + Preparation of composite hydrogels Step 1: Preparation of PBA-Gel / OSA basic hydrogel; (1) Preparation of PBA-Gel: Same as in Example 1.

[0049] (2) Preparation of OSA: Weigh 3 g of sodium alginate (molecular weight 180,000 Da, G content 58%), add 60 mL of deionized water and 6 mL of anhydrous ethanol, adjust pH to 5.5, add NaIO4 (molar ratio of NaIO4 to uronic acid units in sodium alginate is 0.3:1), stir at room temperature in the dark for 4 h; add 1.5 mL of ethylene glycol to quench for 30 min, transfer the reaction solution to a 1000 Da dialysis bag for dialysis for 72 h, freeze dry to obtain OSA powder, and increase the oxidation degree of OSA; Step 2: THB / Zn² + Preparation of nanoparticles: Weigh 0.5 g THB and dissolve it in 10 mL PBS buffer. After complete dissolution, add 0.6 g ZnSO4. 7H2O (THB and ZnSO4) 7H2O (mass ratio 1:1.2) was stirred at room temperature for 4 h to obtain a 0.5 wt% nanoparticle dispersion.

[0050] Step 3: Preparation of composite hydrogel: Prepare 30wt% PBA-Gel aqueous solution and 20wt% OSA aqueous solution, and measure 1 mL of the two solutions at a volume ratio of 1:1. Vortex mix for 30s; add 100μL of nanoparticle dispersion, vortex for 10s, and let stand at room temperature for 30 min to form composite hydrogel.

[0051] Example 4: High Loading THB / Zn² + Preparation of composite hydrogels Step 1: Preparation of PBA-Gel / OSA basic hydrogel; (1) Preparation of PBA-Gel: Same as in Example 3.

[0052] (2) Preparation of OSA: Same as in Example 4.

[0053] Step 2: THB / Zn² + Preparation of nanoparticles: Weigh 0.6 g THB and dissolve it in 10 mL PBS buffer. After complete dissolution, add 0.8 g ZnSO4. 7H2O (THB and ZnSO4) The nanoparticle dispersion was obtained by stirring at room temperature for 4 h with 7H2O (mass ratio 1:1.3) at room temperature.

[0054] Step 3: Preparation of composite hydrogel: Prepare 30 wt% PBA-Gel aqueous solution and 20 wt% OSA aqueous solution, and measure 1 mL of the two solutions at a volume ratio of 1:1. Vortex mix for 30 s. Add 200 μL of nanoparticle dispersion, vortex for 10 s, and let stand at room temperature for 30 min to form composite hydrogel.

[0055] Experimental results: This invention achieves a stable adhesive hydrogel through the cross-linking reaction of phenylboronic esters and Schiff bases. The mechanism of its dynamic cross-linking gelation and self-healing is as follows: aldehyde groups and amino groups synergistically undergo a dynamic Schiff base reaction, and boronic ester bonds form a strongly adhesive, injectable, and self-healing hydrogel. The formation and addition of metal-flavonoid nanoparticles, a key component in the preparation of this hydrogel, not only enhances the degree of cross-linking and adhesion but also provides antibacterial and anti-inflammatory effects. The gelation time of gelatin / sodium alginate-based hydrogels was detected using the inverted observation method. The adhesiveness of the gelatin / sodium alginate-based hydrogels was assessed by adhesion to porcine skin tissue. Mouse fibroblasts (L929) and human lung epithelial cells (BEAS-2B) were used as experimental cells, cultured in 90% DMEM (high glucose) and 10% FBS at 37°C in a 5% CO2 incubator. The effect of hydrogels with different nanoparticle contents on cell viability was tested using CCK8 reagent. Inflammatory factors (LPS) were used to induce inflammation in macrophages (RAW 246.7) to simulate the inflammatory environment of the infection site. Different groups of hydrogels were co-cultured with these inflammatory factors for 24 h, and the changes in inflammation were observed using DCFH DA probe staining. The anti-inflammatory effect of the hydrogels was determined based on the amount of green fluorescence. The antibacterial properties of the hydrogels were tested using Escherichia coli and Staphylococcus aureus, the main pathogens causing bacterial infections. ROS removal and antibacterial experiments showed that the hydrogel loaded with 0.05 wt% NPs had the best overall performance. Figure 1 The gelation process of this hydrogel is demonstrated. In contrast, the hydrogel after gelation exhibits a significant change to non-flow. Furthermore, with the addition of different amounts of metal nanoparticles, the hydrogel, while changing color, still retains a relatively intuitive gelation morphology transformation. Figure 2 As shown in Figure a, the hydrogel can firmly adhere to the surface of moist pig lungs. Overlap shear test ( Figure 2 (bd) indicates that both the basic hydrogel and the NP-loaded hydrogel exhibit higher adhesion strength than commonly used clinical occlusion agents, with the hydrogel loaded with 0.05 wt% NPs showing the best adhesion performance. Even after adding different amounts of nanoparticles, this hydrogel still maintains good biocompatibility. Figure 3 As can be seen, L929 and BEAS-2B cells under the influence of different hydrogels have high survival rates, indicating that the materials have good biocompatibility. Figure 4 PBA-Gel / OSA / THB 0.05 / Zn 2+ Both THB and metal nanoparticles alone can effectively inhibit the increase in ROS levels in macrophages induced by LPS, demonstrating significant anti-inflammatory and antioxidant potential. Figure 5 Different hydrogels were then mixed with Escherichia coli (E. coli) E.Coli ) and Staphylococcus aureus ( S.aureusThe cells were co-cultured for 8 h, 24 h, and 48 h, and then plated for counting. Compared with the basic hydrogel system, the number of colonies was significantly reduced when the amount of nanoparticles added was 0.05 wt% hydrogel.

[0056] in conclusion: This invention successfully prepared a multifunctional integrated adhesive hydrogel loaded with active ingredients from traditional Chinese medicine. Boric acid-modified gelatin and oxidized sodium alginate form the hydrogel matrix, which is then loaded with metallic flavonoid nanoparticles formed from extracts of the traditional Chinese medicine *Anoectochilus roxburghii* (THB) and zinc ions, resulting in a composite hydrogel with antibacterial, anti-inflammatory, and strong adhesive functions. This material can be used as a clinical occlusion agent, effectively sealing the tissue while preventing bacterial infection or inflammatory reactions, thus solving the problems of poor adhesion, limited functionality, and easy detachment of traditional occlusion materials. It can be precisely adapted to complex clinical scenarios such as pneumothorax treatment, providing a new approach for the clinical treatment of pneumothorax and other soft tissue injuries. Its preparation process is simple, the conditions are mild, and it has high biosafety, filling a technological gap in existing occlusion materials and possessing significant scientific research value and broad clinical translational potential.

[0057] Please note to all technical personnel: Although the present invention has been described according to the specific embodiments above, the inventive concept of the present invention is not limited to this invention. Any modifications that utilize the inventive concept will be included within the scope of patent protection of this patent.

[0058] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A multifunctional integrated hydrogel, characterized in that, The aforementioned multifunctional integrated hydrogel is a dual-network hydrogel formed by the reaction of PBA-Gel and OSA with Schiff base via dynamic borate ester bonds, supporting 2,3,4-trihydroxybenzaldehyde (THB) and Zn. 2+ Self-assembly to form metal-flavonoid nanoparticles (THB / Zn²) + NPs).

2. The multifunctional integrated hydrogel according to claim 1, characterized in that, The metal-flavonoid nanoparticles (THB / Zn²) + NPs embed nanoparticles into a dual-network hydrogel through hydrogen bonding and electrostatic interactions.

3. The multifunctional integrated hydrogel according to claim 1, characterized in that, The 2,3,4-trihydroxybenzaldehyde (THB) mentioned above is a flavonoid phenolic metabolite extracted from Anoectochilus roxburghii.

4. The multifunctional integrated hydrogel according to claim 1, characterized in that, The volume ratio of PBA-Gel to OSA is 1:3 to 3:

1.

5. The multifunctional integrated hydrogel according to claim 4, characterized in that, The volume ratio of PBA-Gel to OSA is 1:

1.

6. The multifunctional integrated hydrogel according to claim 1, characterized in that, The 2,3,4-trihydroxybenzaldehyde (THB) and Zn 2+ The mass ratio is 1:0.5-1:

2.

7. The multifunctional integrated hydrogel according to claim 6, characterized in that, The 2,3,4-trihydroxybenzaldehyde (THB) and Zn 2+ The mass ratio is 1:0.8-1:1.

5.

8. The multifunctional integrated hydrogel according to claim 6, characterized in that, The multifunctional integrated hydrogel contains metal-flavonoid nanoparticles (THB / Zn²). + The content of NPs is 0.01-0.1 wt%.

9. A method for preparing the multifunctional integrated hydrogel according to claim 1, characterized in that, Includes the following steps: Step 1: Construction of the gelatin and sodium alginate hydrogel base system: Vortex mix phenylboronic acid modified gelatin (PBA-Gel) aqueous solution and oxidized sodium alginate (OSA) aqueous solution for 20-40 s, let stand at room temperature for 20-40 min, and crosslink to form a PBA-Gel / OSA base hydrogel with strong tissue adhesion. Step 2: Preparation of metal nanoparticles: The flavonoid compound THB is reacted with the metal ion Zn. 2+ When added together to PBS buffer solution, self-assembly yields metal-flavonoid nanoparticles (THB / Zn²⁺). + NPs); Step 3: Preparation of hydrogel loaded with metal nanoparticles: The prepared metal nanoparticles were added to the PBA-Gel / OSA basic hydrogel system, vortexed for 10 s, and allowed to stand at room temperature for 30 min. The nanoparticles were embedded into the gel network through hydrogen bonding and electrostatic interaction to obtain an adhesive hydrogel with high bioactivity.

10. The multifunctional integrated hydrogel according to claim 9, characterized in that, In step 1, the concentration of phenylboronic acid modified gelatin (PBA-Gel) is 10-40 wt% in aqueous solution, and the concentration of sodium oxidized alginate (OSA) aqueous solution is 8-25 wt%.

11. The application of the multifunctional integrated hydrogel of claim 1 in the preparation of a biodegradable medical occlusion agent for the treatment of pneumothorax.

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