A temperature-visualized intelligent hydrogel patch and its preparation method and application

Abstract

The present invention discloses a temperature-visualized intelligent hydrogel patch and its preparation method and application. The intelligent hydrogel patch is mainly assembled by light-triggered antibacterial hydrogel and temperature-responsive thermochromic liquid crystal; the light-triggered antibacterial hydrogel is gradually grafted with endogenous antibacterial agents and photosensitizers by a chemical grafting method on carboxylated cellulose nanofibers, and then adsorbs photothermal agents, and finally is photocured with methacrylated gelatin; the temperature-responsive thermochromic liquid crystal is self-assembled by hydroxypropyl cellulose, thermoresponsive molecules, and nano-carbon black. The hydrogel has a highly efficient antibacterial effect on drug-resistant bacteria under visible light + near-infrared triggering, and the liquid crystal has a temperature recognition function through color change. When the near-infrared photothermal temperature of the hydrogel rises from 20°C to 56°C, the color of the liquid crystal changes from purple to red, and the yellow area (43°C-48°C) is used as the photothermal treatment area and the orange (>50°C) is used as the overheating mark.

Description

Technical Field

[0001] The present invention belongs to the field of medical dressings, and in particular relates to a temperature-visualized intelligent hydrogel dressing. Background Art

[0002] Hydrogels have dual properties similar to those of solids and liquids, excellent biocompatibility, controllable physical properties, and rich network structures, and are widely used in the field of medical dressings. Hydrogels containing endogenous antimicrobial agents have long-lasting antimicrobial properties, but have disadvantages such as slow antimicrobial effects and insufficient ability to kill drug-resistant bacteria. For light-responsive smart hydrogels, the degree of response can be regulated by accurately controlling the irradiation parameters of light (such as irradiation intensity, wavelength, and time). Photodynamic therapy (PDT) and photothermal therapy (PTT) for light-triggered hydrogel minimally invasive therapies have high antimicrobial properties in a short period of time and will not produce drug resistance, providing new possibilities for light therapy. Photothermal therapy of hydrogels kills bacteria through high temperatures, but excessive heat can damage surrounding healthy tissues. Hydrogels themselves lack the ability to recognize temperature, and thermal imaging devices are often used for temperature monitoring, which is inconvenient to carry and use. At present, smart hydrogels that can synergize treatment with photothermal temperature recognition have not been developed and are of research and development significance. Summary of the Invention

[0003] The present invention aims to provide a temperature-visualized intelligent hydrogel patch, its preparation method, and its application. The patch integrates antibacterial and temperature recognition functions, and has synergistic endogenous and light-triggered exogenous antibacterial and photothermal temperature visualization functions.

[0004] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0005] A temperature-visualized intelligent hydrogel patch comprises an outer layer and an inner layer. The inner layer comprises temperature-responsive thermochromic liquid crystals, and the outer layer comprises light-triggered antibacterial hydrogels. The middle portion of the light-triggered antibacterial hydrogels has a groove structure, and the temperature-responsive thermochromic liquid crystals are loaded into the grooves of the light-triggered antibacterial hydrogels.

[0006] The light-triggered antibacterial hydrogel is obtained by gradually grafting endogenous antibacterial agents and photosensitizers onto carboxylated cellulose nanofibers through a chemical grafting method, then adsorbing a photothermal agent through electrostatic interaction, and then curing it with methacrylated gelatin through ultraviolet light. The temperature-responsive thermochromic liquid crystal is self-assembled from hydroxypropyl cellulose, temperature-responsive molecules, and nano-carbon black.

[0007] The endogenous antibacterial agent is polyaminopropyl biguanide or poly-L-arginine, the photosensitizer is protoporphyrin, meso-tetra(4-carboxyphenyl)porphine or dihydrochlorin e6, the photothermal agent is negatively charged Prussian blue or polydopamine, and the temperature-responsive molecule is polyacrylamide.

[0008] Preferably, the temperature-visualized smart hydrogel patch of the present invention further includes an upper surface layer covering the outer and inner layers, wherein the upper surface layer is a transparent jelly wax sealing film. The jelly wax, as a transparent sealing film, can prevent the temperature-responsive thermochromic liquid crystal from losing water, thereby maintaining the stability of the liquid crystal.

[0009] Furthermore, the preparation of the light-triggered antibacterial hydrogel mainly involves the following steps: subjecting carboxylated cellulose nanofibers and endogenous antibacterial agents to an amidation reaction at room temperature for 20 to 24 hours at a mass ratio of 0.295 to 1.5; subjecting the resulting reaction product to a photosensitizer at a mass ratio of 3.33 to 8.33, and subjecting the resulting reaction product to an amidation reaction at room temperature and in the dark for 18 to 24 hours to obtain light-responsive cellulose nanofibers; then, the photothermal agent is adsorbed through electrostatic interaction; and finally, the photo-triggered antibacterial hydrogel is obtained by ultraviolet light curing with methacrylic gelatin; the mass percentage of the photothermal agent in the light-triggered antibacterial hydrogel is 0.015% to 0.10%, and the mass percentage of the methacrylic gelatin in the light-triggered antibacterial hydrogel is 9.1% to 12.5%.

[0010] Furthermore, the preparation of temperature-responsive thermochromic liquid crystal mainly comprises the following steps: dissolving acrylamide and lithium phenyl-2,4,6-trimethylbenzoylphosphinate in water, adding nano-carbon black, stirring and irradiating with ultraviolet light to induce acrylamide self-polymerization, then adding hydroxypropyl cellulose and mixing evenly, and finally assembling into temperature-responsive thermochromic liquid crystal by standing; the mass percentage of acrylamide in the temperature-responsive thermochromic liquid crystal is 4.33%, the mass percentage of hydroxypropyl cellulose in the temperature-responsive thermochromic liquid crystal is 65.83%, and the mass ratio of nano-carbon black to the temperature-responsive thermochromic liquid crystal is 4.8 μg / g to 11.55 μg / g.

[0011] The temperature visualization intelligent hydrogel patch of the present invention integrates antibacterial and temperature recognition functions, has synergistic endogenous and light-triggered exogenous antibacterial, photothermal temperature visualization functions, and can be used as an antibacterial and photothermal treatment temperature visualization medical patch. The hydrogel layer of the patch has a high-efficiency antibacterial effect on drug-resistant bacteria under visible light / near-infrared triggering, and the liquid crystal layer has a temperature recognition function through color change. When the near-infrared photothermal temperature of the hydrogel rises from 20°C to 56°C, the color of the liquid crystal changes from purple to red, and the yellow area (43°C-48°C) is used as the photothermal treatment area and the orange (>50°C) is used as an overheating mark.

[0012] The present invention has the following beneficial effects:

[0013] (1) The temperature-visualized intelligent hydrogel patch prepared by the present invention has visible light / near-infrared light / temperature stimulus response performance. Its visible light / near-infrared light response is light-triggered photodynamic antibacterial / photothermal antibacterial, and its temperature response is that the liquid crystal recognizes the temperature of the hydrogel through color change. When the hydrogel temperature rises from 20°C to 56°C, the corresponding liquid crystal shows a color transition of purple, blue, cyan, green, yellow, orange, and red. This solves the problem that the temperature of the hydrogel photothermal process cannot be visualized.

[0014] (2) The present invention cleverly designs an intelligent hydrogel patch with visualized temperature on the outer and inner layers. The outer hydrogel has a highly effective antibacterial effect on drug-resistant bacteria under visible light + near-infrared triggering, and the inner liquid crystal has a temperature recognition effect through color change. The outer layer uses functionalized cellulose nanofibers as the skeleton of the hydrogel to gradually graft endogenous antibacterial agents and photosensitizers to provide endogenous antibacterial and light-triggered photodynamic antibacterial effects, and then electrostatic action fixes the photothermal agent to provide photothermal antibacterial effects. When the near-infrared photothermal temperature of the outer hydrogel rises from 20°C to 56°C, the color of the inner liquid crystal changes from purple to red, and the yellow area (43°C-48°C) is used as the photothermal treatment area and the orange (>50°C) is used as an overheating indicator, which provides a new idea for visualizing the hydrogel temperature during the photothermal treatment of infected wounds.

[0015] (3) The present invention prepares a smart hydrogel patch that combines treatment and temperature recognition by combining light-triggered antibacterial hydrogel and temperature-responsive thermochromic liquid crystal. Carboxylated nanofibers are first grafted with amino antibacterial agents through a step-by-step grafting method to provide the nanofibers with long-lasting antibacterial properties. Then, hydrophobic photosensitizers are grafted with amino groups as reaction sites, which enhances the photosensitivity and increases the production of reactive oxygen species. It has good reactive oxygen release performance under white light / red light excitation; functionalized cellulose nanofibers fix the photothermal agent through electrostatic action and have excellent photothermal performance under near-infrared 808nm excitation. The key to the temperature response characteristics of liquid crystals is to control the proportion of hydroxypropyl cellulose and temperature-responsive molecules in the liquid crystal. The higher the proportion of hydroxypropyl cellulose, the more the liquid crystal color moves toward purple and the lower the thermal responsiveness; the more temperature-responsive molecules are introduced, the more the liquid crystal color moves toward red and the greater the thermal responsiveness, thereby controlling the desired color change. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic structural diagram of a temperature-visualized intelligent hydrogel patch of the present invention.

[0017] Figure 2 This is a schematic diagram of the disassembly of a temperature-visualized intelligent hydrogel patch of the present invention.

[0018] Explanation of the reference numerals: 1-outer layer, 2-inner layer, 3-upper layer, 4-groove. DETAILED DESCRIPTION

[0019] As attached Figure 1 、 2 As shown, a temperature-visualized smart hydrogel patch of the present invention includes an outer layer 1 and an inner layer 2, wherein the inner layer 2 is a temperature-responsive thermochromic liquid crystal, and the outer layer 1 is a light-triggered antibacterial hydrogel; the middle portion of the light-triggered antibacterial hydrogel is a groove 4 structure, and the temperature-responsive thermochromic liquid crystal is loaded in the groove 4 of the light-triggered antibacterial hydrogel; as a preferred embodiment, the temperature-visualized smart hydrogel patch of the present invention further includes an upper surface layer 3 covering the outer layer and the inner layer, wherein the upper surface layer 3 is a jelly wax transparent sealing film.

[0020] Example 1

[0021] S1. Preparation of Antimicrobial Cellulose Nanofibers: Disperse 1.25 g of carboxylated cellulose nanofibers evenly with 200 mL of deionized water, place in a 500 mL reaction vessel, then add 0.75 g of N-hydroxysuccinimide and 0.75 g of 1-ethyl-(3-dimethylaminopropyl)carbonyl, and stir for 20 minutes. Dissolve 4 g of polyaminopropyl biguanide in 80 mL of deionized water and, once completely dissolved, slowly add the mixture to the reaction vessel using a pipette. Allow to react at room temperature for 20 hours. Wash the reaction product six times by centrifugation to obtain antimicrobial cellulose nanofibers.

[0022] S2. Preparation of red light responsive cellulose nanofibers: First, weigh 0.3g of meso-tetra(4-carboxyphenyl)porphine and dissolve it in 20g of dimethyl sulfoxide, then add 0.4g of 1-ethyl-(3-dimethylaminopropyl) carbon and 0.6g of N-hydroxysuccinimide, and activate it at room temperature for 20min. Then add the antibacterial cellulose nanofibers (1g) obtained in step S1 to a 500mL beaker, add 200mL of deionized water, and stir under magnetic stirring for 20min. The activated meso-tetra(4-carboxyphenyl)porphine is slowly added to the antibacterial cellulose nanofiber solution and reacted in the dark for 20h at room temperature. The reaction product is centrifuged with deionized water until the supernatant is colorless and the product is red light responsive cellulose nanofibers.

[0023] S3. Preparation of polydopamine photothermal agent: 100 mL of distilled water, 40.0 mL of anhydrous ethanol and 0.2 mL of ammonia water were sealed and stirred at room temperature for 30 min; 130 mg of dopamine hydrochloride was added, and the rotation speed was maintained at 1500-5000 r / min. After 36 h, the reactant was centrifuged and washed with distilled water (16000 rpm, 10 min) 5 times to obtain the polydopamine product, which was stored in a refrigerator at 4°C for later use.

[0024] S4. Preparation of light-triggered antibacterial hydrogel: 1 mL (10 mg / mL) of the polydopamine product (10 mg) prepared in step S3 was ultrasonically dispersed and added to 15 mL (2% solid content) of the red light-responsive cellulose nanofiber (0.3 g) aqueous solution prepared in step S2. The mixture was stirred at room temperature for 6 h, followed by the addition of 1.0 g of methacrylated gelatin and 5.0 mg of lithium phenyl-2,4,6-trimethylbenzoylphosphinate, and stirred evenly. Excess water was removed by rotary evaporation, and a 10 g sample was placed in a mold and refrigerated for 4 h. The resulting sample was then cured by UV light to obtain a light-triggered antibacterial hydrogel with a groove structure in the middle.

[0025] S5. Preparation of temperature-responsive thermochromic liquid crystals: Weigh 3g of water, add 0.45g of acrylamide and 2.5mg of lithium phenyl-2,4,6-trimethylbenzoylphosphinate, add 0.05mL (1mg / mL) of the prepared nanocarbon black solution, and stir while irradiating with ultraviolet light to induce polymerization of the acrylamide monomer. Weigh 6.84g of hydroxypropyl cellulose and add it in batches. Stir thoroughly, centrifuge for 10 minutes to remove bubbles, and then allow to stand to assemble into a cholesteric liquid crystal (i.e., a photoresponsive thermochromic liquid crystal). The total mass of the liquid crystal is 10.39g.

[0026] S6. Preparation of temperature-visualized intelligent hydrogel patch: The temperature-responsive thermochromic liquid crystal prepared in step S5 is loaded into the groove of the molded light-triggered antibacterial hydrogel. The viscosity of the temperature-responsive thermochromic liquid crystal allows it to adhere to the groove of the light-triggered antibacterial hydrogel. The melted jelly wax is free of bubbles and sprayed on the upper surface of the temperature-responsive thermochromic liquid crystal and the light-triggered antibacterial hydrogel. After film formation, it is stored in a refrigerator at 4°C.

[0027] Example 2

[0028] S1. Preparation of antibacterial cellulose nanofibers: Disperse 0.59 g of carboxylated cellulose nanofibers evenly with 120.0 mL of deionized water and place in a 300 mL reaction vessel. Then, dissolve 0.30 g of N-hydroxysuccinimide and 0.30 g of 1-ethyl-(3-dimethylaminopropyl)carbon in 10 mL of deionized water and slowly add to the reaction vessel, stirring for 20 minutes. Dissolve 2 g of polyaminopropyl biguanide in 80.0 mL of deionized water and, after complete dissolution, slowly add to the reaction vessel using a pipette. Allow to react at room temperature for 22 hours to obtain the antibacterial cellulose nanofibers.

[0029] S2. Preparation of white light responsive cellulose nanofibers: 30 mg of protoporphyrin was weighed and dissolved in 5 g of dimethyl sulfoxide, followed by addition of 3 mg of N, N'-carbonyldiimidazole, and activated at room temperature in the dark for 20 min. 0.2 g of the antibacterial cellulose nanofibers obtained in step S1 were then evenly dispersed with 80 mL of deionized water, followed by addition of 15.0 mL of dimethyl sulfoxide and thorough mixing. The activated protoporphyrin was mixed and added to the evenly dispersed fiber solution, and the reaction was carried out in the dark for 24 h at room temperature. The reaction product was centrifuged with deionized water until the supernatant was colorless, and the product was white light responsive cellulose nanofibers.

[0030] S3. Preparation of Prussian Blue Photothermal Agent: Add 5 mL of 1.5 mM citric acid solution dropwise to 60.0 mL of 3.0 mM FeCl₃ solution. Stir at room temperature until uniform. Then, add 60.0 mL of 1.0 mM citric acid solution of K₄[Fe(CN)₆]₆. Wait until the solution turns blue and continue the reaction for 0.5 h. After the reaction is complete, add 100.0 mL of acetone. Dialyze against deionized water for 5 days and collect the prepared Prussian blue by rotary evaporation.

[0031] S4. Preparation of light-triggered antibacterial hydrogel: 0.12 mL (10 mg / mL) of the Prussian blue (1.2 mg) aqueous solution prepared in step S3 was ultrasonically dispersed and added to 12 mL (2% solid content) of the white light-responsive cellulose nanofiber (0.24 g) aqueous solution prepared in step S2. The mixture was stirred at room temperature for 6 h. Then, 1.0 g of methacrylated gelatin and 5.0 mg of lithium phenyl-2,4,6-trimethylbenzoylphosphinate were added and stirred evenly. Excess water was removed by rotary evaporation, and an 8 g sample was obtained. The sample was placed in a mold and refrigerated for 4 h. The sample was then removed and cured by UV light to obtain a light-triggered antibacterial hydrogel with a groove structure in the middle.

[0032] S5. Preparation of temperature-responsive thermochromic liquid crystals: Weigh 3g of water, add 0.45g of acrylamide and 2.5mg of lithium phenyl-2,4,6-trimethylbenzoylphosphinate, then add 0.1mL (1mg / mL) of the prepared nanocarbon black solution and stir while irradiating with ultraviolet light to induce polymerization of the acrylamide monomer. Weigh 6.84g of hydroxypropyl cellulose and add it in batches. Stir thoroughly, centrifuge for 10 minutes to remove bubbles, and then allow the mixture to stand for assembly to form a cholesteric liquid crystal (i.e., a photoresponsive thermochromic liquid crystal). The total mass of the liquid crystal is 10.39g.

[0033] S6. Preparation of temperature-visualized smart hydrogel patch: The temperature-responsive thermochromic liquid crystal prepared in step S5 is loaded into the groove of the molded light-triggered antibacterial hydrogel. The self-adhesiveness of the temperature-responsive thermochromic liquid crystal allows it to adhere to the groove of the light-triggered antibacterial hydrogel. The melted jelly wax is de-bubbled and sprayed on the upper surface of the temperature-responsive thermochromic liquid crystal and the light-triggered antibacterial hydrogel. After film formation, the patch is stored in a refrigerator at 4°C.

[0034] Example 3

[0035] S1. Preparation of antibacterial cellulose nanofibers: Disperse 0.3 g of carboxylated cellulose nanofibers evenly with 100.0 mL of deionized water and place in a 300 mL reaction vessel. Then, weigh 0.15 g of N-hydroxysuccinimide and 0.15 g of 1-ethyl-(3-dimethylaminopropyl)carbonate and dissolve them in 10 mL of deionized water. Slowly add the mixture to the reaction vessel and stir for 20 minutes. Dissolve 0.2 g of poly-L-arginine in 20.0 mL of deionized water. Once completely dissolved, slowly add the mixture to the reaction vessel using a pipette. Allow to react at room temperature for 24 hours to obtain the antibacterial cellulose nanofibers.

[0036] S2. Preparation of red light responsive cellulose nanofibers: First, weigh 30 mg of dihydrochlorin e6 and dissolve it in 5 g of dimethyl sulfoxide, then add 0.1 g of 1-ethyl-(3-dimethylaminopropyl) carbon and 0.2 g of N-hydroxysuccinimide, and activate it at room temperature for 20 min. Then add the antibacterial cellulose nanofibers (0.25 g) obtained in step S1 to a 300 mL beaker, add 150 mL of deionized water, and stir under magnetic stirring for 20 min. The activated dihydrochlorin e6 is slowly added to the antibacterial cellulose nanofiber solution and reacted in the dark at room temperature for 18 h. The reaction product is centrifuged with deionized water until the supernatant is colorless and the product is red light responsive cellulose nanofibers.

[0037] S3. Preparation of Prussian Blue Photothermal Agent: First, prepare 0.5 mol / L potassium ferrocyanide and 1.3 mol / L ferric nitrate. Add 200 mL of potassium ferrocyanide to a 500 mL reaction vessel, then slowly add 100 mL of ferric nitrate dropwise. Continue the reaction for 1.5 hours. After the reaction is complete, dialyze against deionized water for 5 days, then collect the prepared Prussian blue by rotary evaporation.

[0038] S4. Preparation of light-triggered antibacterial hydrogel: 0.20 mL (10 mg / mL) of the Prussian blue (2 mg) solution prepared in step S3 was ultrasonically dispersed and added to 18 mL (2% solid content) of the red light-responsive cellulose nanofiber (0.36 g) aqueous solution prepared in step S2. The mixture was stirred at room temperature for 6 h. Then, 1.0 g of methacrylated gelatin and 5.0 mg of lithium phenyl-2,4,6-trimethylbenzoylphosphinate were added and stirred evenly. Excess water was removed by rotary evaporation to obtain an 11 g sample, which was placed in a mold and refrigerated for 4 h. The sample was then removed and cured by UV light to obtain a light-triggered antibacterial hydrogel with a groove structure in the middle.

[0039] S5. Preparation of temperature-responsive thermochromic liquid crystals: Weigh 3g of water, add 0.45g of acrylamide and 2.5mg of lithium phenyl-2,4,6-trimethylbenzoylphosphinate, then add 0.12mL (1mg / mL) of the prepared nanocarbon black solution and stir while inducing ultraviolet light to self-polymerize the acrylamide monomer. Weigh 6.84g of hydroxypropyl cellulose and add it in batches. Stir thoroughly, centrifuge for 10 minutes to remove bubbles, and then allow the mixture to stand for assembly to form a cholesteric liquid crystal (i.e., a photoresponsive thermochromic liquid crystal). The total mass of the resulting liquid crystal is 10.39g.

[0040] S6. Preparation of temperature-visualized smart hydrogel patch: The temperature-responsive thermochromic liquid crystal prepared in step S5 is loaded into the groove of the molded light-triggered antibacterial hydrogel. The self-adhesiveness of the temperature-responsive thermochromic liquid crystal allows it to adhere to the groove of the light-triggered antibacterial hydrogel. The melted jelly wax is de-bubbled and sprayed on the upper surface of the temperature-responsive thermochromic liquid crystal and the light-triggered antibacterial hydrogel. After film formation, the patch is stored in a refrigerator at 4°C.

[0041] Performance test of the light-responsive temperature-visualized water-smart hydrogel patches prepared in Examples 1, 2, and 3

[0042] ① The temperature visualization smart hydrogel patches prepared in Examples 1, 2, and 3 were subjected to light response performance tests. It was found that the hydrogel layer of Example 2 could continuously produce reactive oxygen species under white light excitation and the hydrogel layers of Examples 1 and 3 could continuously produce reactive oxygen species under red light excitation, with the yield reaching 0.1 μmol / g to 10 μmol / g. In addition, under the conditions of 808 nm near-infrared laser (power 0.7 W cm -2 ) irradiation, the temperature of the hydrogel layer can rise from 27℃ to 56℃.

[0043] ② The temperature visualization smart hydrogel dressings prepared in Examples 1, 2, and 3 were subjected to antibacterial performance tests and wound healing performance evaluations on rats infected with drug-resistant bacteria. The measured results showed that the antibacterial rates of the hydrogel layer of Example 2 under white light excitation and the hydrogel layers of Examples 1 and 3 under red light excitation against Escherichia coli and methicillin-resistant Staphylococcus aureus were both higher than 95.0%, and the antibacterial rates under near-infrared 808nm excitation were both higher than 99.5%. The hydrogel layer of Example 2 under white light + near-infrared 808nm excitation and the hydrogel layers of Examples 1 and 3 under red light excitation against Escherichia coli and methicillin-resistant Staphylococcus aureus were both higher than 95.0%. The antibacterial rates under red light + near-infrared 808nm excitation were both higher than 99.9%; and the wounds of rats infected with methicillin-resistant Staphylococcus aureus were basically healed on the 14th day when the hydrogel layer of Example 2 was treated with white light irradiation, and the wounds of rats infected with methicillin-resistant Staphylococcus aureus were basically healed on the 12th day when the hydrogel layer of Example 2 was treated with white light + near-infrared 808nm irradiation, and the wounds of rats infected with methicillin-resistant Staphylococcus aureus were basically completely healed on the 12th day when the hydrogel layer of Example 2 was treated with white light + near-infrared 808nm irradiation, and the hydrogel layers of Examples 1 and 3 were treated with red light + near-infrared 808nm irradiation.

[0044] ③ The temperature visualization intelligent hydrogel patches prepared in Examples 1, 2, and 3 were subjected to a photothermal temperature recognition test. The near-infrared photothermal temperature of the hydrogel layer was measured to rise from 20°C to 56°C, and the liquid crystal layer was purple at 22-27°C, blue at 28-32°C, cyan at 33-37°C, green at 38-42°C, yellow at 43-48°C, orange at 50-54°C, and red above 55°C. The temperature in the yellow zone was used as the photothermal treatment temperature and orange as an overheating indicator.

Claims

1. A temperature-visualized intelligent hydrogel patch, characterized in that: The invention comprises an outer layer and an inner layer, wherein the inner layer is a temperature-responsive thermochromic liquid crystal, and the outer layer is a light-triggered antibacterial hydrogel. The middle portion of the light-triggered antibacterial hydrogel is a groove structure, and the temperature-responsive thermochromic liquid crystal is loaded in the groove of the light-triggered antibacterial hydrogel. The light-triggered antibacterial hydrogel is obtained by gradually grafting endogenous antibacterial agents and photosensitizers onto carboxylated cellulose nanofibers through a chemical grafting method, then adsorbing a photothermal agent through electrostatic interaction, and then curing it with methacrylated gelatin through ultraviolet light. The temperature-responsive thermochromic liquid crystal is self-assembled from hydroxypropyl cellulose, temperature-responsive molecules, and nano-carbon black. The endogenous antibacterial agent is polyaminopropyl biguanide or poly-L-arginine, the photosensitizer is protoporphyrin, meso-tetrakis(4-carboxyphenyl)porphine or dihydrochlorin e6, the photothermal agent is negatively charged Prussian blue or polydopamine, and the temperature-responsive molecule is polyacrylamide.

2. The temperature-visualized intelligent hydrogel patch according to claim 1, characterized in that: The utility model also comprises an upper surface layer covering the outer layer and the inner layer, wherein the upper surface layer is a jelly wax transparent sealing film.

3. The temperature-visualized intelligent hydrogel patch according to claim 1, characterized in that: The main operations for preparing the light-triggered antibacterial hydrogel are as follows: the carboxylated cellulose nanofibers and the endogenous antibacterial agent are subjected to an amidation reaction at room temperature for 20 to 24 hours at a mass ratio of 0.295 to 1.5; the obtained reaction product and the photosensitizer are subjected to an amidation reaction at room temperature and in the dark for 18 to 24 hours at a mass ratio of 3.33 to 8.33 to obtain light-responsive cellulose nanofibers; the photothermal agent is then adsorbed through electrostatic interaction; and finally, the photo-triggered antibacterial hydrogel is obtained by ultraviolet curing with methacrylic gelatin; the mass percentage of the photothermal agent in the light-triggered antibacterial hydrogel is 0.015% to 0.10%, and the mass percentage of the methacrylic gelatin in the light-triggered antibacterial hydrogel is 9.1% to 12.5%.

4. The temperature-visualized intelligent hydrogel patch according to claim 1, characterized in that: The preparation of temperature-responsive thermochromic liquid crystal mainly comprises the following steps: dissolving acrylamide and lithium phenyl-2,4,6-trimethylbenzoylphosphinate in water, adding nano-carbon black, stirring and irradiating with ultraviolet light to induce acrylamide self-polymerization, then adding hydroxypropyl cellulose and mixing evenly, and finally assembling into temperature-responsive thermochromic liquid crystal by standing; the mass percentage of acrylamide in the temperature-responsive thermochromic liquid crystal is 4.33%, the mass percentage of hydroxypropyl cellulose in the temperature-responsive thermochromic liquid crystal is 65.83%, and the mass ratio of nano-carbon black to the temperature-responsive thermochromic liquid crystal is 4.8 μg / g~11.55 μg / g.

5. Use of the temperature-visualized intelligent hydrogel dressing according to any one of claims 1 to 4 for preparing a temperature-visualized medical dressing for antibacterial and photothermal therapy.

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