Light-operated hydrogel, preparation method and application of light-operated hydrogel in treatment of chronic otitis media

Abstract

The invention relates to the field of medical application of hydrogel, in particular to light-operated hydrogel, a preparation method of the light-operated hydrogel and application of the light-operated hydrogel to treatment of chronic otitis media, and the light-operated hydrogel is prepared by taking gelatin methacryloyl derivatives GelMA and sulfonated chitosan methacryloyl derivatives SCSMA as main framework materials and mixing the gelatin methacryloyl derivatives GelMA and the sulfonated chitosan methacryloyl derivatives SCSMA as auxiliary framework materials. The SCSMA is prepared by introducing a methacryloyl group on a sulfonated chitosan SCS molecular chain, so that the SCSMA is endowed with photo-crosslinking capability, and the SCSMA and GelMA form a three-dimensional network structure under an illumination condition; ofloxacin is loaded on the light-operated hydrogel, LAP is added for realizing a light cross-linking reaction, and CaCl2 is added as a divalent ion regulating agent for enhancing the network stability and regulating and controlling the drug release behavior; the hydrogel disclosed by the invention can exist in a middle ear cavity for a long time and is gradually degraded, meanwhile, the sustained release of a local antibacterial drug is realized, and the problems of high flowability, short drug effect maintaining time, limited local anti-infection effect and the like of traditional ear drops are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the medical application field of biological hydrogel, in particular to a light-controlled hydrogel, a preparation method and application thereof in treating chronic otitis media. BACKGROUND

[0002] Chronic suppurative otitis media (CSOM) is a common and recurrent chronic inflammatory disease of the middle ear, which is mainly characterized by tympanic membrane perforation with long-term purulent secretions. Epidemiological data shows that more than 200 million patients worldwide are affected by this disease, which can cause permanent hearing loss and cause a huge public health burden. The common pathogenic bacteria include Pseudomonas aeruginosa and Staphylococcus aureus, among which Pseudomonas aeruginosa is the main difficulty in treatment due to its strong drug resistance and easy formation of bacterial biofilm.

[0003] Current clinical treatment mainly relies on systemic or local antibiotics. Systemic administration is often difficult to achieve effective drug concentration locally due to insufficient blood supply to the middle ear cavity, and may produce systemic toxic side effects at high doses. Although local ear drops can directly act on the lesion area, they are subject to the high fluidity of the liquid, which is easily discharged through the eustachian tube, and it is difficult to maintain sufficient time in the middle ear cavity, resulting in limited efficacy. At the same time, the long-term or repeated use of antibiotics accelerates the generation of drug-resistant strains, further weakening the effect of traditional treatment.

[0004] In recent years, some new materials have been tried for local drug delivery in the middle ear. For example, temperature-sensitive hydrogels can gel at body temperature to prolong the local drug retention time; nanoparticles, nanoenzymes and exosomes are also being explored for their anti-infective potential. However, these systems still have the following shortcomings: 1. Traditional hydrogels lack intrinsic antibacterial activity and have limited effect on drug-resistant strains and biofilm-related infections; 2. Some hydrogels are complex to prepare and have slow gelling speed, which is not conducive to clinical promotion; 3. Drug release kinetics is uncontrollable, making it difficult to achieve precise local spatiotemporal control; Therefore, in the anatomically small and complex environment of the middle ear, there is an urgent need for a new local drug delivery system that combines fast gelation, good retention, intrinsic antibacterial activity, and controllable drug release performance to improve the treatment of chronic otitis media. SUMMARY

[0005] The purpose of the present application is to solve the above-mentioned deficiencies and provide a light-controlled hydrogel, which can exist in the middle ear cavity for a long time and gradually degrade, while achieving sustained release of local antibacterial drugs, overcoming the problems of traditional ear drops such as high fluidity, short drug efficacy maintenance time, and limited local anti-infective effect.

[0006] To achieve the above-mentioned purpose, a light-controlled hydrogel is designed, which is prepared from gelatin methacryl derivative GelMA and sulfonated chitosan methacryl derivative SCSMA as main skeleton materials, the SCSMA is prepared by introducing methacryl groups on the molecular chain of sulfonated chitosan SCS, so as to endow it with photo-crosslinking ability, and make it form a three-dimensional network structure with GelMA under light conditions.

[0007] Further, the light-controlled hydrogel is loaded with ofloxacin OFL, and a photoinitiator 4-(2-hydroxy-1-(4-methylphenyl)-2-propanone) LAP is added for realizing photo-crosslinking reaction; and calcium chloride CaCl2 is added as a divalent ion regulator to enhance network stability and regulate drug release behavior.

[0008] Further, the mass ratio of the skeleton components GelMA and SCSMA of the light-controlled hydrogel is 5:1.6.

[0009] Further, the addition amount of the photoinitiator LAP accounts for 0.5% of the total mass, the addition amount of OFL accounts for 0.3% of the total mass, and the addition amount of CaCl2 accounts for 0.067% of the total mass.

[0010] Further, the preparation method of the sulfonated chitosan methacryl derivative SCSMA is as shown in the following synthesis route, and specifically includes the following steps: a proper amount of SCS is dissolved in 4wt% acetic acid aqueous solution, a methacrylic anhydride solution is slowly added under light shielding conditions, and stirring reaction is carried out at 40 DEG C for 12h under light shielding conditions; after the reaction is completed, the reaction liquid is added into ultrapure water to terminate the reaction; then the reaction liquid is loaded into a dialysis bag with a molecular weight cut-off of 14000, and dialysis is carried out in ultrapure water for 7 days under light shielding conditions to remove excess small molecules, and water is changed three times a day during the period; finally, the reaction liquid is dried by a freeze dryer to remove water, and a white powder solid sulfonated double bond chitosan SCSMA is obtained; .

[0011] The application also provides a preparation method of the light-controlled hydrogel, which includes the following steps: 1) GelMA and SCSMA are respectively dissolved in ultrapure water, and are heated to complete dissolution in a metal bath under light shielding conditions at 45 DEG C, so as to form a skeleton solution of the light-controlled hydrogel; 2) the GelMA and SCSMA solutions are mixed in proportion, and 0.3% ofloxacin and 0.067% CaCl2 are added; 3) 0.5% of a photoinitiator LAP is added to the obtained mixed liquid to prepare a hydrogel precursor solution, and rapid crosslinking and gelation can be realized after light irradiation.

[0012] Further, in steps 2) and 3), an appropriate amount of CaCl2 is weighed and placed in an EP tube, ultrapure water is added to obtain a CaCl2 solution; an appropriate amount of ofloxacin hydrochloride is weighed and placed in an EP tube, ultrapure water is added; the dissolved GelMA solution is taken with a pipette gun, added to the SCSMA solution, shaken to ensure uniform mixing, then the ofloxacin hydrochloride solution is added, and then the LAP solution and the CaCl2 solution are added, and the mixture is shaken again to ensure uniform mixing; the uniform mixture is poured into a gel forming mold, and a light source is tightly attached to the mold to irradiate for 30 s to obtain a hydrogel.

[0013] The application further provides an application of the light-controlled hydrogel in treating chronic otitis media. The specific method is: the precursor solution is injected into the middle ear cavity through the tympanic membrane, the injection amount of the hydrogel solution is 50 ul, a 405 nm light source is used for irradiation for 20-40 s, a free radical polymerization reaction of the methacryl group is triggered, and a three-dimensional cross-linked hydrogel network is rapidly formed in the middle ear cavity.

[0014] Compared with the prior art, the application has the following advantages: (1) The hydrogel system of the application introduces a light response characteristic, can be quickly cured within seconds of light irradiation, and realizes in-situ gelation in the middle ear cavity, ensuring that the drug is fixed in the local lesion area, and the light-triggered method has the advantages of non-invasiveness and high precision control, without the need for additional chemical cross-linking agents, reducing the risk of potential by-products; (2) The hydrogel of the application has enhanced antibacterial performance, the skeleton material SCSMA endows the material with antibacterial activity, and through electrostatic interaction, the antibacterial effect is achieved, and when used in combination with antibiotics such as ofloxacin, a synergistic effect is produced, significantly improving the inhibition effect on drug-resistant strains, thereby effectively reducing bacterial load and reducing the risk of recurrence; (3) The hydrogel of the application can realize controllable drug release, the porous interconnected network structure helps to release the drug and maintain a stable concentration, and the release kinetics can be controlled by the material composition and light irradiation conditions, thereby reducing the frequency of drug administration and significantly prolonging the retention time of the drug in the middle ear, improving the treatment compliance compared with traditional ear drops; (4) The preparation method of the hydrogel of the application is simple, the raw materials are easy to obtain, the overall cost is low, the process conditions are mild and easy to scale up, and therefore it has good clinical transformation and application prospect; In summary, the application provides a light-controlled hydrogel for treating chronic otitis media, which can exist in the middle ear cavity for a long time and gradually degrade, while realizing the sustained release of local antibacterial drugs, overcoming the problems of traditional ear drops such as strong flowability, short drug efficacy maintenance time, and limited local anti-infection effect. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a synthesis route of the skeleton material SCSMA of the light-controlled hydrogel of the application; Figure 2 NMR characterization chart of the light-controlled hydrogel skeleton material SCSMA of the present application; Figure 3 SEM electron micrograph of the light-controlled hydrogel of the present application; Figure 4 Rheological time scan (G' and G" change with time) of the light-controlled hydrogel of the present application; Figure 5 Rheological frequency scan (G' and G" change with frequency) of the light-controlled hydrogel of the present application; Figure 6 Live and dead staining chart of the light-controlled hydrogel of the present application on Pseudomonas aeruginosa; Figure 7 Crystal violet staining chart of the light-controlled hydrogel of the present application destroying Pseudomonas aeruginosa biofilm; Figure 8 Effect of the light-controlled hydrogel of the present application on cell activity; Figure 9 Otoscope effect chart of the light-controlled hydrogel of the present application treating chronic otitis media; Figure 10 Middle ear lavage liquid colony bright field photo after the light-controlled hydrogel of the present application treating chronic otitis media. DETAILED DESCRIPTION

[0016] The present application provides an antibacterial light-controlled hydrogel for chronic otitis media treatment, which is prepared from gelatin methacryl derivative (GelMA) and sulfonated chitosan methacryl derivative (SCSMA) modified by the present application as the main skeleton material; the SCSMA is prepared by introducing methacryl groups on the molecular chain of sulfonated chitosan (SCS), thereby endowing it with light crosslinking ability, so that it can form a stable three-dimensional network structure with GelMA under light conditions.

[0017] The hydrogel can load antibiotics such as ofloxacin (OFL); add a photoinitiator 4-(2-hydroxy-1-(4-methylphenyl)-2-propanone) (LAP) for realizing the light crosslinking reaction; and add calcium chloride (CaCl2) as a divalent ion regulator to enhance the network stability and regulate the drug release behavior.

[0018] The mass ratio of the hydrogel skeleton components GelMA and SCSMA is 5:1.6, the addition amount of the photoinitiator LAP accounts for 0.5% of the total mass of the system, the addition amount of OFL accounts for 0.3% of the total mass, and the addition amount of CaCl2 accounts for 0.067% of the total mass.

[0019] The present application also provides a preparation method of sulfonated chitosan methacryl derivative (SCSMA), and the synthetic route is as follows: Figure 1As shown, the specific steps include: Weigh 1.5g of SCS and dissolve it in 100mL of 4wt% acetic acid aqueous solution; 6 mL of methacrylic anhydride solution was slowly added dropwise under light-protected conditions, and the mixture was stirred at 40 °C for 12 h under light-protected conditions. After the reaction is complete, add 50 mL of ultrapure water to terminate the reaction. The reaction solution was placed in a dialysis bag with a molecular weight cutoff of 14,000 and dialyzed in ultrapure water for 7 days under light-protected conditions to remove excess small molecules, with the water changed three times a day during the period. The reaction solution was lyophilized to remove moisture, yielding a white powdery solid sulfonated double-bonded chitosan (SCSMA).

[0020] This invention also provides a method for preparing an antibacterial photosensitive hydrogel for the treatment of chronic otitis media, as follows: 1) Dissolve GelMA and SCSMA separately in ultrapure water and heat in a metal bath at 45°C under light-protected conditions until completely dissolved to form the framework solution of the photosensitive hydrogel; 2) Mix GelMA and SCSMA solutions in proportion, and add ofloxacin at a mass fraction of 0.3% and CaCl2 at a mass fraction of 0.067%; 3) Add 0.5% photoinitiator LAP to the obtained mixture to prepare a hydrogel precursor solution, which can be rapidly cross-linked into a gel after light irradiation.

[0021] This invention also provides an application of an antibacterial photosensitive hydrogel in the treatment of chronic otitis media. The specific method involves injecting the precursor solution into the middle ear cavity through the tympanic membrane, with an injection volume of 50 μL. Irradiation with a 405 nm light source for 20–40 seconds triggers the free radical polymerization reaction of methacryloyl groups, rapidly forming a three-dimensional cross-linked hydrogel network in the middle ear cavity.

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments: Example 1: NMR characterization of SCSMA The synthesized SCSMA was dissolved in D2O and characterized using ¹H NMR spectroscopy (NMR spectrometer model: Bruker AM-400).

[0023] Test results are as follows Figure 2 As shown, characteristic hydrogen proton signals of the methacrylyl double bond appear at chemical shifts δ≈5.35 ppm and δ≈5.35-5.65 ppm, proving that the methacrylyl functional group has been successfully introduced into the SCSMA molecule. This result indicates that the method described in this invention can effectively prepare SCSMA with photocrosslinking capability.

[0024] Example 2: Preparation and characterization of an antibacterial photosensitive hydrogel Weigh 30 mg of GelMA into a 1.5 mL EP tube, add 200 μL of ultrapure water, and dissolve it in a metal bath at 45 °C under light-protected conditions. Weigh 9.6 mg of SCSMA into a 1.5 mL EP tube, add 250 μL of ultrapure water, and dissolve it in a metal bath at 45 °C under light-protected conditions. Weigh 3 mg LAP into a 1.5 mL EP tube, add 30 μL of ultrapure water, and dissolve it in a metal bath at 45 °C under light-protected conditions. Weigh 40 mg of calcium chloride into a 5 mL EP tube, add 2 mL of ultrapure water, and obtain a 20 mg / mL calcium chloride solution; Weigh 1.8 mg of ofloxacin hydrochloride into a 1.5 mL EP tube and add 100 μL of ultrapure water; Use a pipette to draw 200 μL of dissolved GelMA solution and add it to 250 μL of SCSMA solution. Shake to ensure thorough mixing. Then add 100 μL of ofloxacin hydrochloride solution, 30 μL of LAP solution, and 20 μL of calcium chloride solution. Shake again to ensure thorough mixing. The hydrogel is obtained by pouring the uniform mixture into a gel mold and irradiating it with a 405nm light source close to the mold for 30 seconds.

[0025] Gel morphology under scanning electron microscopy (SEM), such as Figure 3 As shown, the hydrogel obtained in this embodiment has a loose, porous (honeycomb) network structure.

[0026] The stability of the hydrogel was tested using rheological methods, and the results are as follows: Figure 4 , Figure 5 As shown, the hydrogel rheological test results obtained in this embodiment show that the storage modulus (G′) is always higher than the loss modulus (G″) in the frequency scan and time scan experiments, indicating that a stable cross-linked network has been formed. This suggests that the hydrogel can exist stably in the middle ear cavity for a long time, thereby meeting the needs of chronic otitis media treatment.

[0027] Example 3: In vitro antibacterial ability test of antibacterial light-controlled hydrogel The antibacterial activity of the photosensitive hydrogel against *Pseudomonas aeruginosa* was evaluated using bacterial viability staining. The experimental method was as follows: *Pseudomonas aeruginosa* (ATCC 27853) was selected as the model strain; 100 μL of the prepared hydrogel was added to a 96-well plate, with LB broth as the control group; subsequently, 100 μL of *Pseudomonas aeruginosa* bacterial suspension (10... 6(CFU / mL) and incubate at 37℃ for 6 hours; collect the bacterial culture from each well and transfer to a centrifuge tube, centrifuge at 1000 rpm for 5 minutes; discard the supernatant, wash 2-3 times with PBS; resuspend the bacteria in PBS to approximately 10 CFU / mL. 8 CFU / mL; stain with live / dead fluorescent staining reagent (DMAO / PI), incubate at room temperature in the dark for 15 min, gently mix, take 5–10 μL and drop onto a glass slide, cover with a coverslip, and immediately perform microscopic observation and photography.

[0028] The results are as follows Figure 6 As shown, the red fluorescence (dead bacteria) in the antibacterial photocontrolled hydrogel group was significantly increased, indicating a significant antibacterial effect compared to the control group.

[0029] Example 4: Evaluation of the in vitro anti-biofilm performance of antibacterial light-controlled hydrogels The disruption of *Pseudomonas aeruginosa* biofilm formation by the described antibacterial photocontrolled hydrogel was assessed using crystal violet staining. The experimental method was as follows: *Pseudomonas aeruginosa* (ATCC 27853) was selected as the model strain, and 100 μL of *Pseudomonas aeruginosa* bacterial suspension (10 μL / well) was added to a 96-well plate. 6 (CFU / mL) cultured in a 37 ℃ incubator for 48 h to form a bacterial biofilm; discard the old culture medium, add 100 μL of the formed hydrogel to the well, and continue to culture at 37 ℃ for 12 h; after removing the hydrogel, wash 2-3 times with PBS, air dry, add 100 μL of 0.1% crystal violet solution for staining for 20 min, wash 2-3 times with PBS, air dry, and then take photos for recording.

[0030] The results are as follows Figure 7 As shown, compared with the control group, the crystal violet staining intensity of the antibacterial photosensitive hydrogel treatment group was significantly reduced, indicating that the hydrogel can effectively destroy bacterial biofilms and has good in vitro anti-biofilm properties.

[0031] Example 5: Cytotoxicity test of in vitro antibacterial hydrogel The cytotoxicity of the antibacterial photocontrolled hydrogel extract against primary rat tympanic membrane fibroblasts was evaluated using the CCK-8 assay. The experimental method was as follows: The antibacterial photocontrolled hydrogel was immersed in DMEM medium and incubated at 37 °C for 24 h. The extract was collected and filtered. Primary fibroblasts were seeded in 96-well plates. After cell attachment, the medium was removed, and the antibacterial photocontrolled hydrogel extract was added to the 96-well plates. Cells were cultured for 24, 48, and 72 h. At each time point, CCK-8 reagent was added and the cells were incubated for 2 h. Cell viability was assessed by measuring absorbance at 450 nm using a microplate reader.

[0032] The results are as follows Figure 8As shown, after co-culturing at the three time points, the cell viability remained above 90%, indicating that the antibacterial photocontrolled hydrogel had no significant toxicity to primary rat tympanic membrane fibroblasts and possessed good in vitro cell compatibility.

[0033] Example 6: In vitro antibacterial hydrogel treatment of rats with Pseudomonas aeruginosa-induced chronic otitis media Nine 4-week-old SD rats were randomly divided into three groups of three rats each: a chronic otitis media control group, a chronic otitis media group treated with ofloxacin solution, and a chronic otitis media group treated with antibacterial photosensitive hydrogel. The different treatments for the three groups are as follows: Chronic otitis media group and control group: 50 μL of Pseudomonas aeruginosa (ATCC 27853, ~10 μL) was injected into the tympanic cavity via tympanic membrane injection. 6 A chronic otitis media model was established using CFU / mL, without treatment.

[0034] Chronic otitis media group treated with ofloxacin solution: After the chronic otitis media model was established, 50 μL of ofloxacin at a concentration of 3 mg / mL was injected into the tympanic cavity via tympanic membrane injection for treatment.

[0035] Chronic otitis media treated with antibacterial photocontrolled hydrogel: After the chronic otitis media model was established, 50 μL of antibacterial photocontrolled hydrogel precursor solution was injected into the tympanic cavity via tympanic membrane injection, and then irradiated with a 405 nm light source for 20-40 seconds to allow it to gel in situ and be fixed in the middle ear cavity.

[0036] The tympanic membrane and middle ear lesions of different groups of rats were observed by otoscopy: During the treatment process, the lesions of the tympanic membrane and middle ear cavity of each group of rats were observed on the 14th day after treatment, including congestion, thickening and purulent secretions.

[0037] Middle ear lavage fluid was plate-spread to observe residual bacteria in the middle ear: Rats were sacrificed 14 days after treatment, and the middle ear lavage fluid was collected, diluted, and spread on LB agar plates. After 24 hours of incubation, the results were photographed and recorded.

[0038] The results are as follows Figure 9 , Figure 10 As shown, the inflammation in the middle ear cavity of rats in the control group persisted, accompanied by obvious purulent discharge; the inflammation in the ofloxacin group was partially relieved, but bacteria remained; the inflammatory response in rats in the antibacterial photosensitive hydrogel group was significantly reduced, the tympanic membrane basically returned to normal appearance, and the number of bacteria in the middle ear irrigation fluid was significantly lower than that in the chronic otitis media control group and the chronic otitis media group treated with ofloxacin solution, showing excellent antibacterial and therapeutic effects.

[0039] This invention is not limited to the above-described embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of this invention shall be considered equivalent substitutions and shall be included within the scope of protection of this invention.

Claims

1. A photosensitive hydrogel, characterized in that: The photocontrolled hydrogel is mainly composed of gelatin methacryloyl derivative GelMA and sulfonated chitosan methacryloyl derivative SCSMA. SCSMA is prepared by introducing methacryloyl groups into the sulfonated chitosan SCS molecular chain, thereby endowing it with photocrosslinking ability, so that it can form a three-dimensional network structure with GelMA under light conditions.

2. The photosensitive hydrogel as described in claim 1, characterized in that: The photocontrolled hydrogel is loaded with ofloxacin (OFL) and a photoinitiator 4-(2-hydroxy-1-(4-methylphenyl)-2-propanone) LAP is added to achieve a photocrosslinking reaction; calcium chloride (CaCl2) is added as a divalent ion regulator to enhance network stability and regulate drug release behavior.

3. The photosensitive hydrogel as described in claim 1, characterized in that: The mass ratio of the scaffold component GelMA to SCSMA in the photosensitive hydrogel is 5:1.

6.

4. The photosensitive hydrogel as described in claim 2, characterized in that: The amount of photoinitiator LAP added accounts for 0.5% of the total mass of the system, the amount of OFL added accounts for 0.3% of the total mass, and the amount of CaCl2 added accounts for 0.067% of the total mass.

5. The photosensitive hydrogel as described in claim 1, characterized in that, The preparation method of the sulfonated chitosan methacryloyl derivative SCSMA is as follows, and the specific steps are as follows: Weigh an appropriate amount of SCS and dissolve it in a 4wt% acetic acid aqueous solution. Slowly add methacrylic anhydride solution under light-protected conditions and stir the reaction at 40 °C for 12 h under light-protected conditions. After the reaction is completed, add ultrapure water to the reaction solution to terminate the reaction. Then, put the reaction solution into a dialysis bag with a molecular weight cutoff of 14000 and dialyze it in ultrapure water for 7 days under light-protected conditions to remove excess small molecules. During this period, change the water three times a day. Finally, remove the water from the reaction solution by freeze drying to obtain white powder solid sulfonated double bond chitosan SCSMA. 。 6. A method for preparing a light-controlled hydrogel, characterized in that, Includes the following steps: 1) Dissolve GelMA and SCSMA separately in ultrapure water and heat in a metal bath at 45°C under light-protected conditions until completely dissolved to form the framework solution of the photosensitive hydrogel; 2) Mix GelMA and SCSMA solutions in proportion, and add ofloxacin at a mass fraction of 0.3% and CaCl2 at a mass fraction of 0.067%; 3) Add 0.5% photoinitiator LAP to the obtained mixture to prepare a hydrogel precursor solution, which can be rapidly cross-linked into a gel after light irradiation.

7. The preparation method according to claim 6, characterized in that: In steps 2) and 3), weigh an appropriate amount of CaCl2 and place it in an EP tube, add ultrapure water to obtain a CaCl2 solution; weigh an appropriate amount of ofloxacin hydrochloride and place it in an EP tube, add ultrapure water; use a pipette to draw up the dissolved GelMA solution and add it to the SCSMA solution, shake to ensure uniform mixing, then add the ofloxacin hydrochloride solution, then add the LAP solution and CaCl2 solution, shake again to ensure uniform mixing; pour the uniform mixture into a gel mold and irradiate it with a light source close to the mold for 30 seconds to obtain a hydrogel.

8. The use of the photosensitive hydrogel according to any one of claims 1 to 5 in the treatment of chronic otitis media.

9. The application as described in claim 8, characterized in that: The precursor solution was injected into the middle ear cavity through the tympanic membrane. The injection volume of the hydrogel solution was 50 μL. The solution was irradiated with a 405 nm light source for 20–40 s to trigger the free radical polymerization reaction of methacryloyl groups, which rapidly formed a three-dimensional cross-linked hydrogel network in the middle ear cavity.

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