A fluconazole-silicone foam dressing for incontinence dermatitis prevention and a method for preparing the same

Abstract

The present application provides a kind of fluconazole-silicone foam dressing for incontinence dermatitis protection and its preparation method, the dressing is sequentially waterproof breathable backing layer, fluconazole-containing silicone modified polyurethane foam liquid-absorbing layer, silicone gel skin contact layer from outside to inside;In liquid-absorbing layer, fluconazole is loaded on mesoporous silica nanospheres, and the surface of microsphere is grafted with silicone modified polymer, and the silicone grafting rate of foam liquid-absorbing layer is 8%~15%.The present application has the advantages of high-efficiency liquid absorption, low hardness after liquid absorption, pH targeted drug release, no silicone migration and precipitation, no adhesion and easy removal, can effectively prevent incontinence dermatitis, inhibit secondary fungal infection, reduce secondary skin damage, and meet the clinical incontinence care needs.

Description

Technical Field

[0001] This invention relates to the technical field of medical functional dressings, and in particular to a fluconazole-silicone foam dressing for the protection of incontinence-related dermatitis and its preparation method. Background Technology

[0002] Incontinence-associated dermatitis (IAD) is one of the most common complications in incontinent patients, particularly those who are bedridden for extended periods, elderly patients, patients in intensive care units, and patients with spinal cord injuries. This condition results from prolonged and repeated contact of the skin with irritants such as water, urea, and digestive enzymes in urine and feces, leading to overhydration of the stratum corneum and impaired barrier function. This results in skin erythema, edema, erosion, and exudation, significantly increasing patient suffering and nursing workload. Furthermore, it greatly increases the risk of secondary fungal infections such as Candida albicans, making it a significant high-risk factor for pressure ulcers and a key challenge in clinical incontinence care.

[0003] Currently, the dressings used clinically for the prevention of incontinence-related dermatitis are mainly polyurethane foam dressings, silicone dressings, and medicated dressings, all of which have varying degrees of technical defects: First, they are single-function and lack targeted therapeutic effects. Ordinary foam dressings only have the functions of exudate absorption and physical isolation, without antifungal efficacy, and cannot effectively intervene in fungal infections secondary to incontinence-related dermatitis; existing medicated dressings are mostly a physical mixture of antibacterial drugs and dressing matrix, and the drug release is not targeted. It is continuously released in the slightly acidic environment of normal skin, which can easily lead to fungal resistance with long-term use, and the drug is prone to agglomeration, resulting in excessively high local concentrations, which can irritate damaged and fragile skin. Second, the matrix performance is insufficient, which can easily aggravate skin damage. Ordinary polyurethane foam swells and hardens easily after absorbing liquid, with its hardness increasing by more than 50%. This causes continuous friction on the thin skin around the anus and perineum, exacerbating skin barrier damage. Existing silicone dressings only incorporate silicone gel in the skin contact layer without overall modification of the foam matrix, failing to address the core issue of foam hardening after absorption. Furthermore, silicone and polyurethane matrix have poor compatibility, and silicone is often added through physical blending, which can lead to silicone migration and precipitation, posing biocompatibility risks. Thirdly, their structural synergy is poor, making them unsuitable for the specific needs of incontinence scenarios. Existing dressings struggle to simultaneously meet the multiple requirements of waterproofing and stain prevention, rapid liquid absorption and retention, breathability and moisture retention, non-adhesive removal, and long-lasting antibacterial effects. Summary of the Invention

[0004] In view of this, the present invention proposes a fluconazole-silicone foam dressing for the protection of incontinence-related dermatitis and its preparation method, thereby solving the above problems.

[0005] The technical solution of the present invention is implemented as follows: a fluconazole-silicone foam dressing for the protection of incontinence dermatitis, comprising a waterproof and breathable backing layer, an absorbent layer and a skin contact layer layer stacked sequentially from the outside to the inside;

[0006] The absorbent layer is a fluconazole-containing silicone foam absorbent layer, and the skin contact layer is a silicone gel layer;

[0007] In the fluconazole-containing silicone foam absorbent layer, fluconazole is loaded onto mesoporous silica nanospheres, and the surface of the mesoporous silica nanospheres is grafted with modified polymers.

[0008] The silicone foam absorbent layer is a silicone-modified polyurethane foam absorbent layer with a silicone grafting rate of 8-15%.

[0009] The thickness of the waterproof and breathable backing layer is 10~30μm, the thickness of the liquid-absorbing layer is 200~500μm, and the thickness of the skin contact layer is 20-50μm.

[0010] Furthermore, the mesoporous silica nanospheres loaded with fluconazole have a particle size of 50-200 nm, a mesopore size of 2-5 nm, and a fluconazole loading of 15-30%.

[0011] Furthermore, the modified polymer is a silicone-grafted polymethacrylic acid-polyhydroxyethyl methacrylic acid copolymer obtained by free radical copolymerization of methacrylic acid, hydroxyethyl methacrylic acid and vinylsiloxane, wherein the silicone grafting rate is 10-20%, the polymer has a pH response threshold of 7.2-8.0, which is suitable for the alkaline microenvironment of broken skin in incontinence dermatitis, and achieves targeted drug release.

[0012] Furthermore, in the fluconazole-containing silicone foam absorbent layer, the amount of fluconazole-loaded mesoporous silica nanospheres added is 0.5-5% based on the total mass of the absorbent layer, and the final mass percentage of fluconazole is 0.1-1.2%.

[0013] Furthermore, the silicone gel layer is a silicone polyketone polymer gel, which includes one or more of polydimethylsiloxane, polyaminosiloxane, polyethersiloxane, polyimidesiloxane, and polycarboxysiloxane.

[0014] Furthermore, the waterproof and breathable backing layer is a polyurethane breathable membrane with a moisture permeability of 3000~5000 g / (m²). 2 •24h), hydrostatic pressure ≥30kPa.

[0015] A method for preparing a fluconazole-silicone foam dressing for the protection of incontinence-related dermatitis includes the following steps:

[0016] S1. Preparation of modified drug-loaded microspheres: Fluconazole was loaded into mesoporous silica nanospheres by vacuum impregnation to obtain drug-loaded microspheres; the surface of the drug-loaded microspheres was then activated by silane coupling agent, and modified polymers were grafted onto the surface to obtain modified drug-loaded microspheres.

[0017] S2. Preparation of silicone foam absorbent layer: Polyether polyol, silicone modified polyol, isocyanate, foaming agent, catalyst, crosslinking agent and modified drug-loaded microspheres obtained in step S1 are uniformly mixed, and after in-situ foaming and constant temperature curing, a silicone modified polyurethane foam absorbent layer containing fluconazole is obtained.

[0018] S3. Dressing composite molding: A medical polyurethane adhesive is coated on one side of the waterproof and breathable backing layer and then bonded and cured with the lower surface of the absorbent layer obtained in step S2. Silicone gel is then coated on the upper surface of the absorbent layer and cured to form a silicone gel skin contact layer. Finally, the fluconazole-silicone foam dressing is obtained by slitting.

[0019] Further, in step S1, the impregnation solvent for the vacuum impregnation method is anhydrous ethanol, the impregnation time is 12-24 h, and the vacuum degree is -0.08 to -0.1 MPa; the activation involves dispersing the drug-loaded microspheres in an ethanol solution at a mass-to-volume ratio of 1:20-50 (g:mL), adjusting the pH to 4.0–5.5, adding 5-15% KH570 silane coupling agent (5-15% by mass of the microspheres), hydrolyzing at 25-40°C for 30-60 min, condensing at 60-75°C for 4-8 h, centrifuging, washing, and vacuum drying to obtain surface-activated drug-loaded microspheres; the grafting reaction temperature is 60-80°C, and the reaction time is 4-8 h.

[0020] Further, in step S2, the silicone-modified polyol is prepared by hydrosilylation reaction of polyether polyol and hydrogen-containing silicone oil under platinum catalyst; the specific steps are as follows: the polyether polyol is vacuum dehydrated at 100~120℃ to water content ≤0.05%, 8%~15% of polymethylhydrosiloxane (PHMS) is added, the temperature is raised to 70~90℃ under nitrogen protection, 5~20ppm of Karstedt platinum catalyst is added, the reaction is kept at the temperature for 3~6h, and the product is obtained after termination and vacuum devolatilization.

[0021] The foaming agent is deionized water, the catalyst is dibutyltin dilaurate or bismuth neodecanoate, and the crosslinking agent is triethanolamine.

[0022] The reaction temperature for the in-situ foaming is 25~40℃, and the foaming time is 5~15min;

[0023] The constant temperature curing temperature is 50~60℃, and the curing time is 12~24h.

[0024] Furthermore, the silicone foam absorbent layer comprises, by weight: 80-90 parts of polyether polyol, 10-20 parts of silicone-modified polyol, 38-45 parts of isocyanate, 1.5-3.0 parts of foaming agent, 0.05-0.2 parts of catalyst, 0.3-1.0 parts of crosslinking agent, and 0.5-5 parts of modified drug-loaded microspheres.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] This invention utilizes silicone-modified drug-loaded microspheres to load fluconazole, enabling targeted drug release in the weakly alkaline environment of broken skin in incontinence-associated dermatitis. The inhibitory rate against Candida albicans reaches over 98.7% within 24 hours, while the drug release is extremely low under normal skin conditions, effectively avoiding fungal resistance and skin irritation. This addresses the shortcomings of existing drug-containing dressings, such as non-targeted release and prone to burst release. Furthermore, a polyurethane with a silicone grafting rate of 8%–15% is prepared by in-situ foaming after covalently grafting silicone segments onto a polyether polyol via a hydrosilylation reaction. The foam retains an excellent liquid absorption capacity of up to 19.3 g / g while controlling the hardening rate after liquid absorption to within 15%, solving the problem of hardening and friction damage to the skin after liquid absorption by ordinary foams. Moreover, it has no silicone migration or precipitation and excellent biocompatibility. At the same time, it adopts a three-layer synergistic structure to achieve the integrated effect of physical protection, exudation management, targeted therapy and barrier repair. The drug-loaded microspheres have good compatibility with the foam matrix, the drug is evenly dispersed and the sustained release is stable. The preparation process is simple and controllable, making it suitable for industrial mass production. Detailed Implementation

[0027] To better understand the technical content of this invention, specific embodiments are provided below to further illustrate the invention.

[0028] Unless otherwise specified, the experimental methods used in the embodiments of this invention are all conventional methods.

[0029] Unless otherwise specified, all materials and reagents used in the embodiments of this invention are commercially available.

[0030] Example 1

[0031] A fluconazole-silicone foam dressing for the protection of incontinence dermatitis comprises, from the outside to the inside, a waterproof and breathable backing layer, a fluconazole-containing silicone foam absorbent layer, and a silicone gel skin contact layer.

[0032] Its preparation method is as follows:

[0033] S1. Preparation of modified drug-loaded microspheres

[0034] Drug loading: 10g of mesoporous silica nanospheres (particle size 100nm, mesopore size 3nm) were dispersed in 200mL of anhydrous ethanol, 5g of fluconazole raw material was added, and the mixture was stirred evenly and then immersed in a vacuum environment of -0.09MPa for 18h. The microspheres were collected by centrifugation, washed three times with anhydrous ethanol, and dried under vacuum at 45℃ for 12h to obtain drug-loaded microspheres. The fluconazole loading was found to be 22.3%.

[0035] Surface activation: The above drug-loaded microspheres were dispersed in an ethanol / water mixture (volume ratio 9:1) at a mass-to-volume ratio of 1:35 (g:mL). The mixture was ultrasonically dispersed for 20 min to form a uniform suspension. The pH of the system was adjusted to 4.8 with acetic acid. 1 g of KH570 silane coupling agent (10% of the mass of the drug-loaded microspheres) was added. The mixture was stirred and hydrolyzed at 30 °C for 45 min. Then, the temperature was raised to 70 °C and refluxed with stirring for 6 h to condense the mixture. The supernatant was discarded by centrifugation. The microspheres were washed three times with anhydrous ethanol and dried under vacuum at 50 °C for 8 h to obtain surface-activated drug-loaded microspheres.

[0036] Surface grafting: The activated drug-loaded microspheres were added to a three-necked flask, 100 mL of anhydrous ethanol was added, and the mixture was ultrasonically dispersed. Nitrogen gas was purged for 30 min to remove oxygen. 5 g of methacrylic acid, 3 g of hydroxyethyl methacrylate, and 2 g of vinylsiloxane were added. After stirring evenly, 0.1 g of azobisisobutyronitrile initiator was added. The temperature was raised to 70 °C, and free radical polymerization was carried out under nitrogen protection for 6 h. The microspheres were collected by centrifugation, washed three times with anhydrous ethanol, and vacuum dried to obtain modified drug-loaded microspheres. The silicone grafting rate of the surface-grafted polymer was 15%, and the pH response threshold was 7.4.

[0037] S2. Preparation of silicone foam absorbent layer

[0038] Preparation of silicone-modified polyol: In a dry reactor, 100g of polyether polyol (Mn=2000, functionality 3) and 15g of hydrogen-containing silicone oil (hydrogen content 0.8%) were added, along with Karstedt platinum catalyst (5ppm as Pt). The reaction was carried out at 80℃ under nitrogen protection for 4 hours to obtain silicone-modified polyol. The silicone grafting rate was 11.2%, the hydroxyl value was 33mgKOH / g, and the viscosity at 25℃ was 2200mPa·s.

[0039] Prepare the raw materials according to the following weight ratio: 85 parts of polyether polyol (PPG-3000, medical grade), 15 parts of silicone-modified polyol, 42 parts of diphenylmethane diisocyanate (MDI) (-NCO to -OH molar ratio 1.1:1), 2.2 parts of deionized water (foaming agent), 0.12 parts of bismuth neodecanoate (catalyst), 0.6 parts of triethanolamine (crosslinking agent), and 2.5 parts of modified drug-loaded microspheres.

[0040] Foaming preparation: The above-mentioned polyether polyol, silicone-modified polyol, foaming agent, catalyst, crosslinking agent, and modified drug-loaded microspheres were added to the reaction vessel and stirred at high speed until uniform. Then MDI was added and stirred at high speed for 10 seconds. The mixture was then quickly poured into a mold and foamed in situ at 30°C for 10 minutes. After foaming, the mixture was placed in a 55°C oven for constant temperature curing for 18 hours. After demolding, the mixture was sliced ​​to obtain a silicone-modified polyurethane foam liquid-absorbing layer with a thickness of 350 μm.

[0041] S3, Dressing Composite Molding

[0042] A 20μm thick polyurethane breathable membrane was selected as the waterproof and breathable backing layer, with a moisture permeability of 4000g / (m²). 2 • 24h), withstand hydrostatic pressure of 35kPa; uniformly coat one side of the backing layer with medical polyurethane adhesive, and composite it with the lower surface of the absorbent layer obtained in step 3, and cure at 40℃ for 2h; then uniformly coat the upper surface of the absorbent layer with liquid medical addition-type silicone gel, and cure at 80℃ for 15min to form a silicone gel skin contact layer with a thickness of 35μm (Shore 00 hardness 10), cut according to specifications, package, and sterilize with ethylene oxide to obtain the fluconazole-silicone foam dressing.

[0043] Example 2

[0044] This embodiment provides a fluconazole-silicone foam dressing for the protection of incontinence-related dermatitis. The preparation steps are basically the same as in Example 1, with the only difference being:

[0045] In the preparation of silicone-modified polyols, the amount of hydrogen-containing silicone oil added is 8% of the mass of the polyether polyol;

[0046] The foam absorbent layer formulation is as follows: 90 parts polyether polyol, 10 parts silicone-modified polyol, 38 parts medical-grade MDI, 1.5 parts deionized water, 0.05 parts dibutyltin dilaurate, 0.3 parts triethanolamine, and 0.5 parts modified drug-loaded microspheres;

[0047] In-situ foaming temperature 25℃, foaming time 15min, constant temperature curing temperature 50℃, curing time 24h;

[0048] The resulting foam absorbent layer has a thickness of 200 μm and a silicone grafting rate of 8.1%; the waterproof and breathable backing layer has a thickness of 10 μm; and the silicone gel skin contact layer has a thickness of 20 μm.

[0049] Example 3

[0050] This embodiment provides a fluconazole-silicone foam dressing for the protection of incontinence-related dermatitis. The preparation steps are basically the same as in Example 1, with the only difference being:

[0051] In the preparation of silicone-modified polyols, the amount of hydrogen-containing silicone oil added is 15% of the mass of the polyether polyol;

[0052] The foam absorbent layer formula is as follows: 80 parts polyether polyol, 20 parts silicone-modified polyol, 45 parts medical-grade MDI, 3.0 parts deionized water, 0.2 parts bismuth neodecanoate, 1.0 part triethanolamine, and 5 parts modified drug-loaded microspheres.

[0053] In-situ foaming temperature 40℃, foaming time 5min, constant temperature curing temperature 60℃, curing time 12h;

[0054] The obtained foam absorbent layer has a thickness of 500 μm and a silicone grafting rate of 14.8%; the waterproof and breathable backing layer has a thickness of 30 μm; and the silicone gel skin contact layer has a thickness of 50 μm.

[0055] Comparative Example 1

[0056] This comparative example provides a foam dressing, the preparation steps of which are basically the same as those in Example 1, the only difference being that: no silicone-modified polyol is added to the foam absorbent layer formulation, and 100 parts of ordinary polyether polyol are used. The other raw materials, dosages and process parameters are completely the same as those in Example 1.

[0057] Comparative Example 2

[0058] This comparative example provides a foam dressing, the preparation steps of which are basically the same as those in Example 1. The difference is that: instead of preparing silicone-modified polyol in advance, 85 parts of ordinary polyether polyol (PPG-3000) and 15 parts of side-chain hydrogen-containing silicone oil (polymethylhydrosiloxane) are physically stirred evenly to replace the 85 parts of polyether polyol and 15 parts of silicone-modified polyol in Example 1. The remaining raw materials, dosages, foaming processes, and composite molding steps are completely the same as those in Example 1.

[0059] Comparative Example 3

[0060] This comparative example provides a drug-containing foam dressing. The preparation steps are basically the same as those in Example 1, except that: the surface of the drug-loaded microspheres is not grafted with silicone-modified polymers, and fluconazole is directly physically mixed with the polyurethane foam matrix. The remaining process parameters are completely consistent with those in Example 1.

[0061] Comparative Example 4

[0062] This comparative example provides a medicated foam dressing. The preparation steps are basically the same as those in Example 1. The difference is that the polymer grafted onto the surface of the drug-loaded microspheres is a silicone-free modified polymethacrylic acid-hydroxyethyl methacrylic acid copolymer (without adding vinylsiloxane, and the rest of the grafting process is completely the same). All other raw materials, formulations, and process parameters are completely the same as those in Example 1.

[0063] I. Performance Testing

[0064] 1. Liquid absorption ratio test: According to YY / T 0471.1-2004 "Test methods for contact wound dressings - Part 1: Liquid absorbency", take a dressing sample with a diameter of 2cm, weigh the dry weight, immerse it in physiological saline at 37℃, soak it until constant weight, take it out, use filter paper to absorb the free liquid on the surface, weigh the wet weight, and calculate according to the formula: Liquid absorption ratio = (Wet weight - Dry weight) / Dry weight.

[0065] 2. Hardness improvement rate test after liquid absorption: Using a Shore 00 hardness tester, first measure the dry hardness of the dressing, and then measure the wet hardness after liquid saturation. Calculate the hardness improvement rate according to the formula: Hardness improvement rate = (Wet hardness - Dry hardness) / Dry hardness × 100%.

[0066] 3. In vitro drug release test: According to the release test method of Part IV of the 2025 edition of the Chinese Pharmacopoeia, pH 5.5 acetate-sodium acetate buffer (simulating normal skin environment) and pH 7.4 phosphate buffer (simulating damaged skin environment) were used as release media. The samples were taken at 37℃ and 100 rpm for 24 hours and 7 days, respectively. The fluconazole content was determined by HPLC and the cumulative drug release rate was calculated.

[0067] 4. Silicone migration and precipitation rate test: The dressing sample was immersed in physiological saline at 37℃ and kept at a constant temperature for 7 days. The content of characteristic peaks of siloxane was quantitatively detected by infrared spectroscopy, and the mass of precipitated silicone was calculated as the proportion of the total mass of initial silicone in the dressing.

[0068] 5. Drug dispersion uniformity test: 10 parallel samples of equal mass were randomly selected from the absorbent layer of the dressing, and the fluconazole content of each sample was determined by HPLC. The relative standard deviation (RSD) of the content was calculated. The smaller the RSD, the more uniform the drug dispersion.

[0069] 6. Candida albicans inhibition rate test: According to GB / T 20944.3-2008 "Evaluation of antimicrobial properties of textiles - Part 3: Shaking method", the number of viable bacteria after the sample is shaken and contacted with Candida albicans bacterial solution for 24 hours is tested, and the inhibition rate is calculated.

[0070] 7. Removal Adhesion and Skin Irritation Tests: For removal adhesion, refer to the peel strength test method in YY / T 0148-2006 "General Requirements for Medical Adhesive Tapes". Use detached pigskin for 24 hours, then remove and observe the adhesion. For skin irritation, refer to GB / T 16886.10-2017 "Biological Evaluation of Medical Devices Part 10: Irritation and Skin Sensitization Tests". Use rabbit skin irritation test, observe for 72 hours after application for 24 hours, calculate the irritation response score, and evaluate the irritation level.

[0071] Test Results

[0072]

[0073]

[0074] The dressing prepared in this embodiment of the invention has both excellent absorbency and softness, with an absorbency of 17.2~19.3 g / g. At the same time, the hardness increase rate after absorption is only 10.80%~14.70%, which is much lower than that of Comparative Example 1 and Comparative Example 2. This solves the core pain point of ordinary polyurethane foam dressings hardening after absorption and easily causing friction damage to the fragile skin of incontinent patients, and verifies the optimization effect of silicone covalent grafting modification on the performance of foam matrix.

[0075] The dressing of this invention has precise pH-responsive targeted drug release performance. In the example, the drug release rate of normal skin in a slightly acidic environment (pH 5.5) is only 2.70%~3.80% after 24 hours, which can avoid fungal resistance and skin irritation caused by non-specific drug release. In the alkaline environment (pH 7.4) of broken skin, the drug release rate reaches 79.30%~85.10% after 24 hours, and the cumulative release rate of 7 days exceeds 95%, which can achieve targeted antibacterial treatment, significantly better than the comparative example 3 without targeted design.

[0076] The dressing of this invention exhibits excellent stability and uniform drug dispersion. In Example 7, the silicone migration and precipitation rate was only 0.20%~0.30%, far lower than that of Comparative Example 2, which uses physically blended silicone. There is no risk of silicone precipitation or performance degradation over long-term use. The drug dispersion uniformity RSD is as low as 1.90%~2.80%, significantly better than Comparative Examples 3 and 4. This verifies the good compatibility between the silicone modification on the surface of the drug-loaded microspheres and the foam matrix, which can avoid microsphere aggregation and ensure stable and controllable sustained drug release.

[0077] The dressing of this invention has excellent antibacterial effect and safety in use. The example shows that the antibacterial rate against Candida albicans reaches 98.70%~99.50% in 24 hours, which can effectively intervene in fungal infections secondary to incontinence dermatitis. At the same time, it does not require removal and adhesion and does not cause skin irritation, perfectly meeting the clinical protection and treatment needs of incontinence dermatitis.

[0078] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A fluconazole-silicone foam dressing for the protection of incontinence-related dermatitis, characterized in that, It includes a waterproof and breathable backing layer, an absorbent layer, and a skin contact layer, which are layered sequentially from the outside to the inside; The absorbent layer is a fluconazole-containing silicone foam absorbent layer, and the skin contact layer is a silicone gel layer; In the fluconazole-containing silicone foam absorbent layer, fluconazole is loaded onto mesoporous silica nanospheres, and the surface of the mesoporous silica nanospheres is grafted with modified polymers. The silicone foam absorbent layer is a silicone-modified polyurethane foam absorbent layer with a silicone grafting rate of 8-15%. The thickness of the waterproof and breathable backing layer is 10~30μm, the thickness of the liquid-absorbing layer is 200~500μm, and the thickness of the skin contact layer is 20-50μm.

2. The fluconazole-silicone foam dressing as described in claim 1, characterized in that, The mesoporous silica nanospheres loaded with fluconazole have a particle size of 50-200 nm, a mesoporous pore size of 2-5 nm, and a fluconazole loading of 15-30%.

3. The fluconazole-silicone foam dressing as described in claim 1, characterized in that, The modified polymer is a silicone-grafted polymethacrylic acid-polyhydroxyethyl methacrylic acid copolymer obtained by free radical copolymerization of methacrylic acid, hydroxyethyl methacrylic acid and vinylsiloxane, wherein the silicone grafting rate is 10~20%.

4. The fluconazole-silicone foam dressing as described in claim 1, characterized in that, In the fluconazole-containing silicone foam absorbent layer, the amount of fluconazole-loaded mesoporous silica nanospheres added is 0.5-5% based on the total mass of the absorbent layer, and the final mass percentage of fluconazole is 0.1-1.2%.

5. The fluconazole-silicone foam dressing as described in claim 1, characterized in that, The silicone gel layer is a silicone polyketone polymer gel, which includes one or more of polydimethylsiloxane, polyaminosiloxane, polyethersiloxane, polyimidesiloxane, and polycarboxysiloxane.

6. The fluconazole-silicone foam dressing as described in claim 1, characterized in that, The waterproof and breathable backing layer is a polyurethane breathable membrane with a moisture permeability of 3000~5000 g / (m²). 2 •24h), hydrostatic pressure ≥30kPa.

7. A method for preparing a fluconazole-silicone foam dressing for the protection of incontinence-related dermatitis as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. Preparation of modified drug-loaded microspheres: Fluconazole was loaded into mesoporous silica nanospheres by vacuum impregnation to obtain drug-loaded microspheres; the surface of the drug-loaded microspheres was then activated by silane coupling agent, and modified polymers were grafted onto the surface to obtain modified drug-loaded microspheres. S2. Preparation of silicone foam absorbent layer: Polyether polyol, silicone modified polyol, isocyanate, foaming agent, catalyst, crosslinking agent and modified drug-loaded microspheres obtained in step S1 are uniformly mixed, and after in-situ foaming and constant temperature curing, a silicone modified polyurethane foam absorbent layer containing fluconazole is obtained. S3. Dressing composite molding: A medical polyurethane adhesive is coated on one side of the waterproof and breathable backing layer and then bonded and cured with the lower surface of the absorbent layer obtained in step S2. Silicone gel is then coated on the upper surface of the absorbent layer and cured to form a silicone gel skin contact layer. Finally, the fluconazole-silicone foam dressing is obtained by slitting.

8. The preparation method according to claim 7, characterized in that, In step S1, The impregnation solvent in the vacuum impregnation method is anhydrous ethanol, the impregnation time is 12~24h, and the vacuum degree is -0.08~-0.1MPa; The activation process involves dispersing drug-loaded microspheres in an ethanol solution at a mass-to-volume ratio of 1:20-50 (g:mL), adjusting the pH to 4.0–5.5, adding 5-15% KH570 silane coupling agent (5-15% by mass of the microspheres), hydrolyzing at 25-40°C for 30-60 min, and then performing a condensation reaction at 60-75°C for 4-8 h. The microspheres are then centrifuged, washed, and vacuum dried to obtain surface-activated drug-loaded microspheres. The grafting reaction temperature is 60~80℃, and the reaction time is 4~8h.

9. The preparation method according to claim 7, characterized in that, In step S2, The silicone-modified polyol is prepared by hydrosilylation reaction of polyether polyol and hydrogen-containing silicone oil under platinum catalyst; the foaming agent is deionized water, the catalyst is dibutyltin dilaurate or bismuth neodecanoate, and the crosslinking agent is triethanolamine. The reaction temperature for the in-situ foaming is 25~40℃, and the foaming time is 5~15min; The constant temperature curing temperature is 50~60℃, and the curing time is 12~24h.

10. The preparation method according to claim 7, characterized in that, The silicone foam absorbent layer comprises, by weight: 80-90 parts of polyether polyol, 10-20 parts of silicone-modified polyol, 38-45 parts of isocyanate, 1.5-3.0 parts of foaming agent, 0.05-0.2 parts of catalyst, 0.3-1.0 parts of crosslinking agent, and 0.5-5 parts of modified drug-loaded microspheres.

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