A preparation method of a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy

Abstract

This invention relates to a method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy, belonging to the field of composite material-based hydrogels, and applied to the treatment of infected deep burn wounds. The preparation method of this invention is as follows: Curcumin is coated with β-cyclodextrin (β-CD), and after centrifugation, freeze-drying, and grinding, β-CD@Cur is obtained. Tannic acid is reacted with gallium nitrate hydrate to obtain tannic acid-gallium ion (TA-Ga). 3+ Sodium lignosulfonate and acrylic acid were added to the sodium alginate solution and stirred thoroughly. Then N'N-methylenebisacrylamide was added, and after the reaction was complete, β-CD@Cur and TA-Ga were added. 3+ With ammonium persulfate stirring, the prepared pregel was poured into a mold and placed in an environment of 60°C for in-situ free radical polymerization to obtain β-CD@Cur / TA-Ga 3+ / PAA / LS hydrogel. This invention's dressing possesses both antioxidant and synergistic antibacterial properties, enabling precise adaptation to infected deep second-degree burn wounds. It effectively inhibits infection, reduces inflammation, and promotes tissue repair, while exhibiting excellent biocompatibility and significant clinical application potential.

Description

Technical Field

[0001] This invention relates to a method for preparing a gel dressing, and more particularly to a method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy, belonging to the field of medical dressing preparation technology. Background Technology

[0002] Deep second-degree burns refer to burns that penetrate deep into the dermis, leaving some of the reticular dermis intact. The healing process is complex, often accompanied by significant exudation, residual necrotic tissue, and microcirculatory disturbances, making them highly susceptible to bacterial colonization and infection. Without timely and effective intervention, infection can further aggravate tissue damage, delay wound healing, and even lead to serious complications such as sepsis, endangering the patient's life. Therefore, developing wound dressings with highly effective antibacterial, anti-inflammatory, and healing-promoting functions is of great significance for the treatment of infected deep second-degree burn wounds.

[0003] Currently, commonly used dressings for burn wound infections in clinical practice mainly include silver ion dressings, povidone-iodine dressings, and antibiotic-loaded dressings. Among these, silver ion dressings are widely used due to their broad-spectrum antibacterial properties; however, long-term use can lead to the accumulation of silver ions in the body, posing a potential toxicity risk, and some studies have reported increased bacterial tolerance to silver ions. While antibiotic dressings can effectively inhibit infection, their efficacy is limited by the increasingly serious problem of bacterial resistance, especially against methicillin-resistant Staphylococcus aureus (MRSA), where traditional antibiotic dressings are often ineffective. Furthermore, most existing dressings have limited functionality, making it difficult to simultaneously address multiple needs such as antibacterial, anti-inflammatory, antioxidant, and tissue regeneration promotion. For the irregular wounds often associated with deep second-degree burns, traditional sheet dressings have poor adhesion and are prone to causing secondary damage during changes, affecting treatment outcomes.

[0004] In recent years, the "Trojan horse" antibacterial strategy based on interfering with iron metabolism has attracted widespread attention. Gallium ions (Ga³⁺), due to their similar ionic radius and coordination chemistry to iron ions (Fe³⁺), can be recognized and transported into the bacterial cell by the bacterial iron uptake system, competitively replacing iron ions in key metabolic enzymes. This disrupts core metabolic processes such as the bacterial respiratory chain and DNA synthesis, achieving precise antibacterial action. This strategy does not rely on the mechanism of action of traditional antibiotics and has the unique advantage of being less likely to induce drug resistance. Researchers in this field have conducted a series of fruitful studies on this strategy. Patent publication CN202310404123.0 discloses a gallium porphyrin complex / silk fibroin antibacterial dressing, pointing out that the most significant advantage of gallium ions compared to other metal antibacterial agents is their good biocompatibility and effectiveness against various multidrug-resistant bacteria. Developing novel antibacterial materials that are less likely to induce drug resistance has become an urgent need in this field. Patent CN202310389638.8 discloses an injectable antibacterial fistula-sealing hydrogel. The hydrogel is prepared through metal-organic coordination between hyaluronic acid and Ga³⁺, exhibiting shear-thinning, rapid self-healing, adhesion, and antibacterial properties. A series of patents filed by Dalian University of Technology in 2023 (CN116617446A, WO2024229644A1) disclose a controlled-release gallium ion double-crosslinked antibacterial hydrogel dressing. Using N-isopropylacrylamide, chitosan, and other raw materials, it achieves rapid high-temperature release and slow-release control of Ga³⁺ through a temperature-responsive mechanism, exhibiting skin-like mechanical flexibility and good water absorption and swelling properties. Associate Professor Liang Kuneng and Researcher Deng Yi's team at Sichuan University have jointly developed a "Trojan horse" bio-heterojunction that combines gallium (III) with phototherapy (PTT / PDT). Due to the similarity between gallium (III) and iron (III), the gallium (III) in this material can be actively taken up by bacteria, disrupting the electron transport chain and inhibiting bacterial respiration, thereby achieving effective and rapid sterilization.

[0005] In addition, significant progress has been made in recent years in the development of hydrogel dressings that combine photothermal and ion synergistic antibacterial properties to inhibit multidrug-resistant bacteria. Patent CN202410962798.1 discloses a photothermal responsive hydrogel dressing that inhibits multidrug-resistant bacteria. Its hydrogel framework includes carboxymethyl chitosan, gelatin, periodate-polymer, and water, and is loaded with a metal-polyphenol complex as a photothermal agent. After irradiation with 808nm near-infrared light for 5 minutes, the hydrogel temperature can rise from 20℃ to 75℃, achieving an inhibition rate of over 99.9% against multidrug-resistant bacteria. Patent CN202310651066.0 discloses a multifunctional hydrogel dressing for treating bacterial wound infections, enabling multi-pathway management of wounds infected with drug-resistant bacteria. Patent CN202310083233.1 discloses a hydrogel dressing that combines photothermal and silver ion synergistic antibacterial properties to address the problems of AgNPs' tendency to clump and their sudden release causing cytotoxicity.

[0006] In summary, existing technologies have made significant progress in areas such as gallium ion "Trojan horse" antibacterial strategies, photothermal synergistic antibacterial agents, and inhibition of multidrug-resistant bacteria. Some literature has explicitly stated that "less induced drug resistance" is one of the technological advantages of gallium-based antibacterial materials. However, existing technologies still have the following shortcomings: First, the loading efficiency and release behavior control of gallium ion antibacterial materials are not ideal. Existing gallium-based antibacterial dressings mostly use a single loading method, resulting in limited gallium ion loading. Furthermore, the release process mainly relies on single-factor responses of temperature or pH, lacking a multi-faceted intelligent response mechanism for the complex microenvironment of deep second-degree burn infected wounds, making it difficult to achieve precise release on demand. Second, the antibacterial strategies are relatively singular. Although there are reports of photothermal synergy with silver ions and photothermal synergy with gallium ions, research on organically combining the active uptake antibacterial mechanism of gallium ions with the anti-inflammatory and antioxidant functions of natural polyphenolic compounds to form a multi-target synergistic antibacterial system is rarely reported. Natural polyphenolic compounds such as tannic acid and curcumin have shown application potential in the field of wound repair due to their good antioxidant, anti-inflammatory and biocompatibility properties. However, the poor water solubility and low bioavailability of curcumin limit its direct application in hydrophilic hydrogel dressings.

[0007] Third, existing dressings are insufficient to meet the multiple clinical needs of deep second-degree burn treatment. Deep second-degree burn wounds require not only highly effective antibacterial properties but also anti-inflammatory and swelling-reducing effects, clearance of excess reactive oxygen species, and promotion of dermal regeneration. Simultaneously, they must possess good wound adhesion, injectability, and self-healing properties to adapt to irregular wound surfaces. Existing dressings with single or insufficiently integrated functions cannot fully meet these requirements. Therefore, how to provide a multifunctional gel dressing that can comprehensively meet the treatment needs of deep second-degree burn wounds has not yet been addressed. Summary of the Invention

[0008] To address the above problems, the present invention aims to provide a solution with multiple functions including synergistic antibacterial properties, self-repair, pH-responsive release, and antioxidant properties, which can effectively promote deep tissue regeneration. Preparation method for healing high-degree burn wounds.

[0009] To achieve the above objectives, the technical solution is as follows:

[0010] 1. A method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy, characterized in that the preparation method comprises the following steps:

[0011] a. Preparation of β-CD@Cur

[0012] Dissolve 0.30-0.90 g of Cur in 3.00-6.00 mL of acetone and sonicate for 10-40 min. Further, dissolve 1.00-4.00 g of β-CD in 15.00-55.00 mL of deionized water and stir for 10-40 min. Slowly add the Cur-acetone solution to the β-CD solution using a dropper. Stir for 12-48 h, collect, centrifuge, freeze-dry for 12-48 h, and then grind for subsequent use.

[0013] b. TA-Ga 3+ Solution synthesis

[0014] Dissolve 0.50-2.00 g of Ga(NO3)3·xH2O and 0.40-1.60 g of TA separately in 10.00-40.00 mL of ultrapure water, and stir for 2-5 h until fully dissolved. Slowly add the Ga(NO3)3·xH2O solution to the TA solution using a dropper, add 1.00 M NaOH (100-400 μL), and stir for 1-4 h to ensure thorough mixing.

[0015] c. β-CD@Cur / TA-Ga 3+ Preparation of / PAA / LS hydrogel

[0016] β-CD@Cur / TA-Ga was prepared using a one-pot method. 3+ For the / PAA / LS hydrogel, first dissolve 0.10-0.40 g of SA in 20.00-80.00 mL of deionized water, then add 0.20-0.80 g of LS and 3.50-13.5 g of AA, followed by 0.03-0.12 g of MBA. Stir the reaction for 3-6 hours. Then add TA-Ga... 3+Add 1.00-4.00 g of β-CD@Cur powder to the precursor solution, and finally add 0.03-0.12 g of APS. Stir for 5-20 min, then slowly and evenly pour the prepared pregel into a mold. Place the mold in a drying oven at 60-80℃ for 1.00-4.00 h, and then perform in-situ free radical polymerization to obtain the gel. Immerse the gel in deionized water to wash away unreacted substances.

[0017] The high mechanical strength of hydrogels can prevent gel dressings from being damaged by external forces. This invention introduces acrylic acid (AA) into the gel preparation process, forming a polyacrylic acid chemical cross-linking network through temperature-initiated polymerization, thereby enhancing the physical and mechanical properties of the gel dressing.

[0018] 2. The method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy according to claim 1, characterized in that the additives for the antibacterial properties of the gel dressing are tannic acid (TA) and gallium ions (Ga). 3 + ).

[0019] 3. The method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy according to claim 1, characterized in that the additives used to enhance the physical and mechanical strength of the hydrogel are sodium lignosulfonate (LS) and acrylic acid (AA).

[0020] 4. The method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy according to claim 1, characterized in that the additives with excellent antioxidant properties in the gel dressing are tannic acid (TA) and curcumin.

[0021] The present invention provides a method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy, which has the following advantages compared with the prior art:

[0022] 1) One-pot preparation of β-CD@Cur / TA-Ga 3+ / PAA / LS gel dressings are easy to use, require no intermediate separation, and are suitable for large-scale production.

[0023] 2) The sodium alginate, sodium lignosulfonate, tannic acid, curcumin, etc., selected in this invention are all naturally sourced materials with good biocompatibility and biodegradability. TA-Ga 3+ The synergistic effect endows the gel with excellent antibacterial activity, while avoiding the problems of cytotoxicity, in vivo accumulation and allergic reactions that may be caused by traditional silver ion dressings or antibiotic dressings, thus significantly improving the safety of clinical application.

[0024] 3) This invention utilizes the pH sensitivity of polyacrylic acid to accelerate the release of active ingredients in the weakly acidic microenvironment of infected wounds, while slowing down the release in normal tissue environments. This achieves a balance between on-demand antibacterial properties and long-lasting retention, avoiding the problems of sudden or insufficient drug release.

[0025] 4) This invention significantly improves the water solubility of curcumin through β-cyclodextrin inclusion technology, enabling it to be uniformly dispersed in a hydrophilic hydrogel network, thereby endowing the dressing with anti-inflammatory, antioxidant, and moderately angiogenic functions. Furthermore, curcumin and tannic acid synergistically remove excess reactive oxygen species (ROS) from the wound surface, inhibit inflammatory responses, and promote collagen deposition and re-epithelialization, ultimately accelerating wound healing. Attached Figure Description

[0026] Figure 1 This is a scanning electron microscope (SEM) image of the β-CD@Cur / TA-Ga³⁺ / PAA / LS hydrogel. It shows the three-dimensional porous network structure of the hydrogel.

[0027] Figure 2 It is β-CD@Cur / TA-Ga 3+ Diagram showing the antibacterial properties of / PAA / LS hydrogel against different bacteria.

[0028] Figure 3 The antioxidant capacity of β-CD@Cur / TA-Ga³⁺ / PAA / LS hydrogel is shown in Figure a. Figure a represents the antioxidant rate of the gel sample against free radicals; Figure b represents the antioxidant capacity of β-CD@Cur / TA-Ga³⁺ / PAA / LS hydrogel at different concentrations.

[0029] Figure 4 It is β-CD@Cur / TA-Ga 3+ / PAA / LS hydrogel's responsive drug release with Ga 3+ The cumulative release curves are shown in Figure a. Figure a shows the drug release curve; Figure b shows the in vitro gallium ion release curve.

[0030] The present invention will now be described in detail with reference to specific embodiments.

[0031] Example 1

[0032] 1. A method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy.

[0033] a. Preparation of β-CD@Cur

[0034] 0.30 g (0.49 wt%) of Cur was dissolved in 4.00 mL (5.14 wt%) of acetone and sonicated for 10 min. Further, 3.00 g (4.88 wt%) of β-CD was dissolved in 55.00 mL (89.49 wt%) of deionized water and stirred for 20 min. The Cur-acetone solution was slowly added dropwise to the β-CD solution using a dropper. After stirring for 24 h, the solution was collected, centrifuged, freeze-dried for 36 h, and then ground for further use.

[0035] b. TA-Ga 3+ Solution synthesis

[0036] 0.50 g (1.58 wt%) of Ga(NO3)3·xH2O and 0.80 g (2.52 wt%) of TA were dissolved separately in 30.00 mL (94.59 wt%) of ultrapure water and stirred for 2 h until completely dissolved. The Ga(NO3)3·xH2O solution was slowly added dropwise to the TA solution using a dropper. 1.00 M NaOH (400 μL) (1.31 wt%) was added and stirred for 1 h to ensure thorough mixing.

[0037] c. β-CD@Cur / TA-Ga 3+ Preparation of / PAA / LS hydrogel

[0038] β-CD@Cur / TA-Ga was prepared using a one-pot method. 3+ For the / PAA / LS hydrogel, firstly, 0.10 g (0.18 wt%) of SA was dissolved in 40.00 mL (71.02 wt%) of deionized water. Then, 0.60 g (1.07 wt%) of LS and 13.5 g (23.97 wt%) of AA were added, followed by 0.03 g (0.05 wt%) of MBA. The mixture was stirred for 3 hours. Next, TA-Ga... 3+ Add 2.00 g (3.55 wt%) of β-CD@Cur powder to the precursor solution, and finally add 0.09 g (0.16 wt%) of APS. Stir for 20 min, then slowly and evenly pour the prepared pregel into a mold and place it in a forced-air drying oven at 70 °C for 4 h for in-situ free radical polymerization to obtain the gel. Immerse the gel in deionized water to wash away unreacted substances.

[0039] 2. Performance Testing

[0040] The following tests used the hydrogel prepared in Example 1 as the sample.

[0041] (1) Blood compatibility test

[0042] Results: The hemolysis rate was <2%, which meets the requirements for hemolysis rate (usually <5%) for biomedical materials, indicating that the gel has no significant risk of hemolysis.

[0043] (2) Biocompatibility (CCK-8 assay)

[0044] Cells: L929 fibroblasts, cultured in gel extract for 24 h.

[0045] Results: According to the GB / T16886.5-2017 standard for cytotoxicity analysis, a cell viability rate below 70.0% indicates that the material has a certain degree of toxicity and cannot be used as a biomedical material. Our dressings all exhibited cell viability rates greater than 90%, demonstrating that these hydrogels have excellent biocompatibility and are non-cytotoxic.

[0046] Example 2

[0047] 1. A method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy.

[0048] a. Preparation of β-CD@Cur

[0049] 0.50 g (2.13 wt%) of Cur was dissolved in 5.00 mL (16.84 wt%) of acetone and sonicated for 20 min. Further, 4.00 g (17.06 wt%) of β-CD was dissolved in 15.00 mL (63.97 wt%) of deionized water and stirred for 30 min. The Cur-acetone solution was slowly added dropwise to the β-CD solution using a dropper. After stirring for 36 h, the solution was collected, centrifuged, freeze-dried for 48 h, and then ground for further use.

[0050] b. TA-Ga 3+ Solution synthesis

[0051] 0.10 g (2.36 wt%) of Ga(NO3)3·xH2O and 1.20 g (2.84 wt%) of TA were dissolved separately in 40.00 mL (94.55 wt%) of ultrapure water and stirred for 3 h until completely dissolved. The Ga(NO3)3·xH2O solution was slowly added dropwise to the TA solution using a dropper. 1.00 M NaOH (100 μL) (0.25 wt%) was added and stirred for 3 h to ensure thorough mixing.

[0052] c. β-CD@Cur / TA-Ga 3+ Preparation of / PAA / LS hydrogel

[0053] β-CD@Cur / TA-Ga was prepared using a one-pot method. 3+For the / PAA / LS hydrogel, firstly, 0.20 g (0.30 wt%) of SA was dissolved in 60.00 mL (88.65 wt%) of deionized water. Then, 0.80 g (1.18 wt%) of LS and 3.5 g (5.17 wt%) of AA were added, followed by 0.06 g (0.09 wt%) of MBA. The reaction was stirred for 4 hours. Next, TA-Ga... 3+ Add 3.00 g (4.43 wt%) of β-CD@Cur powder to the precursor solution, and finally add 0.12 g (0.18 wt%) of APS. Stir for 15 min, then slowly and evenly pour the prepared pregel into a mold and place it in a forced-air drying oven at 75 °C for 1 h for in-situ free radical polymerization to obtain the gel. Immerse the gel in deionized water to wash away unreacted substances.

[0054] 2. Performance Testing

[0055] The following tests used the hydrogel prepared in Example 2 as the sample.

[0056] (1) Blood compatibility test

[0057] Results: The hemolysis rate was <2%, which meets the requirements for hemolysis rate (usually <5%) for biomedical materials, indicating that the gel has no significant risk of hemolysis.

[0058] (2) Biocompatibility (CCK-8 assay)

[0059] Cells: L929 fibroblasts, cultured in gel extract for 24 h.

[0060] Results: According to the GB / T16886.5-2017 standard for cytotoxicity analysis, a cell viability rate below 70.0% indicates that the material has a certain degree of toxicity and cannot be used as a biomedical material. Our dressings all exhibited cell viability rates greater than 90%, demonstrating that these hydrogels have excellent biocompatibility and are non-cytotoxic.

[0061] Example 3

[0062] 1. A method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy.

[0063] a. Preparation of β-CD@Cur

[0064] 0.70 g (1.69 wt%) of Cur was dissolved in 6.00 mL (11.44 wt%) of acetone and sonicated for 30 min. Further, 1.00 g (2.41 wt%) of β-CD was dissolved in 35.00 mL (84.46 wt%) of deionized water and stirred for 40 min. The Cur-acetone solution was slowly added dropwise to the β-CD solution using a dropper. The mixture was stirred for 48 h, collected, centrifuged, freeze-dried for 12 h, and then ground for further use.

[0065] b. TA-Ga 3+ Solution synthesis

[0066] 1.50 g (11.27 wt%) of Ga(NO3)3·xH2O and 1.60 g (12.03 wt%) of TA were dissolved separately in 10.00 mL (75.14 wt%) of ultrapure water and stirred for 4 h until fully dissolved. The Ga(NO3)3·xH2O solution was slowly added dropwise to the TA solution using a dropper. 1.00 M NaOH (200 μL) (1.56 wt%) was added and stirred for 4 h to ensure thorough mixing.

[0067] c. β-CD@Cur / TA-Ga 3+ Preparation of / PAA / LS hydrogel

[0068] β-CD@Cur / TA-Ga was prepared using a one-pot method. 3+ For the / PAA / LS hydrogel, firstly, 0.30 g (0.33 wt%) of SA was dissolved in 80.00 mL (87.32 wt%) of deionized water. Then, 0.20 g (0.22 wt%) of LS and 7.0 g (7.64 wt%) of AA were added, followed by 0.09 g (0.01 wt%) of MBA. The mixture was stirred and reacted for 5 hours. Next, TA-Ga... 3+ Add 4.00 g (4.36 wt%) of β-CD@Cur powder to the precursor solution, and finally add 0.03 g (0.03 wt%) of APS. Stir for 20 min, then slowly and evenly pour the prepared pregel into a mold and place it in a forced-air drying oven at 60 °C for 2 h for in-situ free radical polymerization to obtain the gel. Immerse the gel in deionized water to wash away unreacted substances.

[0069] The following tests used the hydrogel prepared in Example 3 as the sample.

[0070] (1) Blood compatibility test

[0071] Results: The hemolysis rate was <2%, which meets the requirements for hemolysis rate (usually <5%) for biomedical materials, indicating that the gel has no significant risk of hemolysis.

[0072] (2) Biocompatibility (CCK-8 assay)

[0073] Cells: L929 fibroblasts, cultured in gel extract for 24 h.

[0074] Results: According to the GB / T16886.5-2017 standard for cytotoxicity analysis, a cell viability rate below 70.0% indicates that the material has a certain degree of toxicity and cannot be used as a biomedical material. Our dressings all exhibited cell viability rates greater than 90%, demonstrating that these hydrogels have excellent biocompatibility and are non-cytotoxic.

[0075] Example 4

[0076] 1. A method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy.

[0077] a. Preparation of β-CD@Cur

[0078] 0.90 g (1.79 wt%) of Cur was dissolved in 3.00 mL (4.71 wt%) of acetone and sonicated for 40 min. Further, 2.00 g (3.98 wt%) of β-CD was dissolved in 45.00 mL (89.52 wt%) of deionized water and stirred for 10 min. The Cur-acetone solution was slowly added dropwise to the β-CD solution using a dropper. After stirring for 12 h, the solution was collected, centrifuged, freeze-dried for 24 h, and then ground for further use.

[0079] b. TA-Ga 3+ Solution synthesis

[0080] 2.00 g (8.81 wt%) of Ga(NO3)3·xH2O and 0.40 g (1.76 wt%) of TA were dissolved separately in 20.00 mL (88.06 wt%) of ultrapure water and stirred for 5 h until completely dissolved. The Ga(NO3)3·xH2O solution was slowly added dropwise to the TA solution using a dropper. 1.00 M NaOH (300 μL) (1.37 wt%) was added and stirred for 1 h to ensure thorough mixing.

[0081] c. β-CD@Cur / TA-Ga 3+ Preparation of / PAA / LS hydrogel

[0082] β-CD@Cur / TA-Ga was prepared using a one-pot method. 3+For the / PAA / LS hydrogel, firstly, 0.40 g (1.23 wt%) of SA was dissolved in 20.00 mL (61.58 wt%) of deionized water. Then, 0.40 g (1.23 wt%) of LS and 10.5 g (32.33 wt%) of AA were added, followed by 0.12 g (0.37 wt%) of MBA. The reaction was stirred for 6 hours. Next, TA-Ga... 3+ Add 1.00 g (3.08 wt%) of β-CD@Cur powder to the precursor solution, and finally add 0.06 g (0.18 wt%) of APS. Stir for 5 min, then slowly and evenly pour the prepared pregel into a mold and place it in a forced-air drying oven at 65℃ for 3 h for in-situ free radical polymerization to obtain the gel. Immerse the gel in deionized water to wash away unreacted substances.

[0083] 2. Performance Testing

[0084] The following tests used the hydrogel prepared in Example 4 as the sample.

[0085] (1) Blood compatibility test

[0086] Results: The hemolysis rate was <2%, which meets the requirements for hemolysis rate (usually <5%) for biomedical materials, indicating that the gel has no significant risk of hemolysis.

[0087] (2) Biocompatibility (CCK-8 assay)

[0088] Cells: L929 fibroblasts, cultured in gel extract for 24 h.

[0089] Results: According to the GB / T16886.5-2017 standard for cytotoxicity analysis, a cell viability rate below 70.0% indicates that the material has a certain degree of toxicity and cannot be used as a biomedical material. Our dressings all exhibited cell viability rates greater than 90%, demonstrating that these hydrogels have excellent biocompatibility and are non-cytotoxic.

[0090] The gel dressing obtained by the method described in this invention has multiple functions, including synergistic antibacterial properties, self-repair, pH-responsive release, and antioxidant properties, and can achieve deep-seated therapeutic effects. Long-lasting antibacterial effect for infected wounds of severe burns, and can be widely used in deep burns. This research has clinical application value in the treatment of infected burn wounds and can be further expanded to the repair and treatment of various infected wounds such as chronic refractory wounds, diabetic foot ulcers, surgical incision infections, and pressure injuries. It has good clinical translational value and market application prospects.

[0091] The above descriptions are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto.

Claims

1. A method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy, characterized in that, It is prepared from the following raw materials: gallium nitrate hydrate (Ga(NO3)3·xH2O), sodium lignosulfonate (LS), acrylic acid (AA), tannic acid (TA), curcumin (Cur), β-cyclodextrin (β-CD), N'N-methylenebisacrylamide (MBA), and ammonium persulfate (APS).

2. The method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy according to claim 1, characterized in that, Includes the following steps: a. Preparation of β-CD@Cur Dissolve 0.30-0.90 g of Cur in 3.00-6.00 mL of acetone and sonicate for 10-40 min. Further, dissolve 1.00-4.00 g of β-CD in 15.00-55.00 mL of deionized water and stir for 10-40 min. Slowly add the Cur-acetone solution to the β-CD solution using a dropper. Stir for 12-48 h, collect, centrifuge, freeze-dry for 12-48 h, and then grind for subsequent use. b. TA-Ga 3+ Solution synthesis Dissolve 0.50-2.00 g of Ga(NO3)3·xH2O and 0.40-1.60 g of TA separately in 10.00-40.00 mL of ultrapure water, and stir for 2-5 h until fully dissolved. Slowly add the Ga(NO3)3·xH2O solution to the TA solution using a dropper, add 1.00 M NaOH (100-400 μL), and stir for 1-4 h to ensure thorough mixing. c. β-CD@Cur / TA-Ga 3+ Preparation of / PAA / LS hydrogel β-CD@Cur / TA-Ga was prepared using a one-pot method. 3+ For the / PAA / LS hydrogel, first dissolve 0.10-0.40 g of SA in 20.00-80.00 mL of deionized water, then add 0.20-0.80 g of LS and 3.50-13.5 g of AA, followed by 0.03-0.12 g of MBA. Stir the reaction for 3-6 hours. Then add TA-Ga... 3+ Add 1.00-4.00 g of β-CD@Cur powder to the precursor solution, and finally add 0.03-0.12 g of APS. Stir for 5-20 min, then slowly and evenly pour the prepared pregel into a mold. Place the mold in a forced-air drying oven at 60-80℃ for 1.00-4.00 h, and then perform in-situ free radical polymerization to obtain the gel. Immerse the gel in deionized water to wash away unreacted substances.

3. The method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy according to claim 1, characterized in that, The antibacterial additives in the gel dressing are tannic acid (TA) and gallium ions (Ga). 3+ ).

4. The method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy according to claim 1, characterized in that, The additives used to enhance the physical and mechanical strength of the hydrogel are sodium lignosulfonate (LS) and acrylic acid (AA).

5. The method for preparing a synergistic antibacterial gel dressing based on a gallium ion "Trojan horse" strategy according to claim 1, characterized in that, The gel dressing contains tannic acid (TA) and curcumin as additives with excellent antioxidant properties.

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