A glucomannan-based composite dressing patch and a preparation method thereof

Abstract

The present application relates to the technical field of dressings, in particular to a composite dressing patch based on glucomannan and a preparation method thereof. First, glucomannan is compounded with alpha cellulose, so that the structural functional group -OH on the alpha cellulose chain and the hydrogen bond network formed by the glucomannan in water act, the functional group -OH extends outward along the cellulose molecular structure, thereby realizing that the cellulose molecules are inserted in the glucomannan network structure, and the mechanical strength of the glucomannan hydrogel is enhanced. Secondly, amino beta cyclodextrin treated by amino functionalization is selected and grafted to the functional group -OH of the glucomannan and alpha cellulose through citric acid. Finally, the drug curcumin is dispersed in the mixed solution. Since the beta-cyclodextrin has a hydrophobic cavity, it can load the hydrophobic curcumin through host-guest interaction, thereby preparing a dressing patch with good sustained release effect and moisturizing effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of dressings, in particular to a composite dressing patch based on glucomannan and a preparation method thereof. BACKGROUND

[0002] Medical dressings are one of the most widely used medical materials today. Traditional dressings are divided into dry gauze dressings and oil gauze dressings, which have no promoting effect on the wound healing process. With the development of material science, great breakthroughs have been made in dressing technology, mainly in replacing damaged skin and continuously acting until the wound heals and the skin lesion heals, while also providing comprehensive protection for the wound to prevent secondary injury and infection, and retaining body electrolytes to create good conditions for promoting wound healing. There are many types of modern dressings, including silver dressings, calcium alginate dressings, foam dressings, hydrocolloid dressings and hydrogel dressings. Among them, hydrogel dressings are particularly common on the market, and they are favored by consumers because they are not sticky to the wound, easy to remove, can automatically adjust the moisture of the wound, and have the ability to absorb a small amount of exudate.

[0003] Glucomannan is a non-toxic and harmless non-ionic water-soluble polysaccharide that widely exists in nature and has good film-forming properties. It is a good drug carrier and can be used to prepare hydrogel dressings. However, the mechanical strength of natural glucomannan hydrogel is low, which limits its application in medical dressings. Therefore, it is necessary to invent a composite dressing based on glucomannan. SUMMARY

[0004] The present application aims to provide a composite dressing patch based on glucomannan and a preparation method thereof to solve the problems raised in the background art.

[0005] To solve the above technical problems, the present application provides the following technical solution: a composite dressing patch based on glucomannan and a preparation method thereof, comprising the following steps:

[0006] Step 1: Mix glucomannan powder, alpha-cellulose powder and deionized water, stir for 30-60 min at elevated temperature to form a uniform sol;

[0007] Step 2: Add amino beta cyclodextrin powder to deionized water and ultrasonic for 15-20 min; add citric acid and sodium dihydrogen phosphate in 3-5 portions and react under pressure to obtain a mixed solution, cool and reserve;

[0008] Step 3: Add the uniform sol in step 1 to the mixed solution in step 2, add curcumin, ultrasonic for 25-30 min, heat to 60-70℃ and react for 2-3 h to obtain a glucomannan composite hydrogel dressing; bond the glucomannan composite hydrogel dressing with a carrier to obtain a glucomannan composite dressing patch.

[0009] Further, in step 1, the amount of each component is 10-30 parts by weight of glucomannan powder, 3-4 parts of alpha-cellulose powder, 500 parts of deionized water.

[0010] Further, in step 1, the reaction temperature is 50-60℃; the stirring time is 30-60min, and the stirring speed is 200-500rpm.

[0011] Further, in step 2, the amount of each component is 4-15 parts by weight of amino beta cyclodextrin powder, 350-400 parts of deionized water solution, 0.88-3.4 parts of citric acid, and 3-4.2 parts of sodium dihydrogen phosphate.

[0012] Further, in step 2, the pressure reaction temperature is 100-120℃, and the reaction time is 5-6h.

[0013] Further, in step 3, the amount of each component is 15-20 parts by weight of the uniform sol in step 1, 3-5 parts of the mixed solution in step 2, and 0.003-0.005 parts of curcumin.

[0014] Further, in step 3, the carrier is any one of polyurethane film, polycaprolactone film, polylactide film, and polyvinylidene fluoride.

[0015] Compared with the prior art, the present application has the following beneficial effects: the present application uses glucomannan as the main raw material and prepares a hydrogel dressing patch through modification and grafting. The present application comprises the following steps: first, glucomannan is compounded with alpha-cellulose. The structure function group -OH is in a flat state on the cellulose chain, which extends outward along the cellulose molecular structure, so that the hydroxyl group of cellulose can easily obtain hydrogen bonds; and the glucomannan molecules can combine with a large number of water molecules to form a hydrogen bond network through hydrogen bonds, molecular dipole moment and other intermolecular forces in the aqueous solution, so that the alpha-cellulose can be inserted into the network structure of the glucomannan to enhance the mechanical strength of the glucomannan hydrogel. By limiting the amount of alpha-cellulose added, the glucomannan hydrogel can have good adhesive strength. Secondly, amino beta cyclodextrin is selected, and the carboxyl group on the citric acid reacts with the amino group on the surface of the amino beta cyclodextrin and the hydroxyl group on the surface of the composite hydrogel to graft the beta cyclodextrin onto the glucomannan and alpha-cellulose. Finally, the drug curcumin is dispersed in water and added to the composite hydrogel. Since the beta-cyclodextrin has a hydrophobic cavity, it can load the hydrophobic curcumin through host-guest interaction. The hydrogel dressing patch prepared by the present application has high drug loading rate and good drug release effect, and the release time is more than 15 days. Moreover, it can provide long-acting moisturizing. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0017] The raw materials used in the following examples and their sources are as follows:

[0018] Glucomannan powder (CAS No. 11078-31-2) was purchased from Hubei Wande Chemical Co., Ltd.; a-cellulose powder (CAS No. 9012-19-5) was purchased from Shandong Jinliwang Industry Co., Ltd.; aminobeta cyclodextrin powder (CAS No. 29390-67-8) was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.; citric acid (CAS No. 77-92-9) was purchased from Shandong Lemon Biochemical Co., Ltd.; sodium dihydrogen phosphate (7558-80-7) was purchased from Suzhou Senya Chemical Technology Co., Ltd.; curcumin (CAS No. 458-37-7) was purchased from Nanjing Chemical Reagent; polyurethane film was purchased from Cognex, model Baymedix FD.

[0019] Example 1

[0020] Step 1: 10 g of glucomannan powder, 3 g of a-cellulose powder and 500 g of deionized water were mixed, and the temperature was raised to 50°C; stirring for 30 min to form a uniform sol;

[0021] Step 2: 4 g of aminobeta cyclodextrin powder was added to 350 g of deionized water and ultrasonicated for 15 min; 0.88 g of citric acid and 3 g of sodium dihydrogen phosphate were added in three portions, and a mixed solution was obtained by pressure reaction at 100°C for 5 h, and then the mixed solution was cooled and prepared for use;

[0022] Step 3: 15 g of the uniform sol in step 1 was added to 3 g of the mixed solution in step 2, 3 mg of curcumin was added, ultrasonicated for 25 min, the temperature was raised to 60°C, and the reaction was carried out for 2 h to obtain a glucomannan composite hydrogel dressing; the glucomannan composite hydrogel dressing was bonded and compounded with a polyurethane film to obtain a glucomannan composite dressing.

[0023] Example 2

[0024] Step 1: 20 g of glucomannan powder, 3.5 g of a-cellulose powder and 500 g of deionized water were mixed, and the temperature was raised to 55°C; stirring for 45 min to form a uniform sol;

[0025] Step 2: 8 g of aminobeta cyclodextrin powder was added to 375 g of deionized water and sonicated for 17 min; 1.6 g of citric acid and 3.5 g of sodium dihydrogen phosphate were added in 4 portions and reacted at 110 °C for 5.5 h under pressure to obtain a mixed solution, which was cooled and reserved;

[0026] Step 3: 18 g of the homogeneous sol in step 1 was added to 4.2 g of the mixed solution in step 2, 4 mg of curcumin was added, and sonicated for 30 min, and then heated to 65 °C and reacted for 2.5 h to obtain a glucomannan composite hydrogel dressing; the glucomannan composite hydrogel dressing was bonded and compounded with a polyurethane film to obtain a glucomannan composite dressing.

[0027] Example 3

[0028] Step 1: 30 g of glucomannan powder, 4 g of a-cellulose powder and 500 g of deionized water were mixed and heated to 60 °C; stirred for 60 min to form a homogeneous sol;

[0029] Step 2: 15 g of aminobeta cyclodextrin powder was added to 400 g of deionized water and sonicated for 20 min; 3.4 g of citric acid and 4.2 g of sodium dihydrogen phosphate were added in 5 portions and reacted at 120 °C for 6 h under pressure to obtain a mixed solution, which was cooled and reserved;

[0030] Step 3: 20 g of the homogeneous sol in step 1 was added to 5 g of the mixed solution in step 2, 5 mg of curcumin was added, and sonicated for 30 min, and then heated to 70 °C and reacted for 3 h to obtain a glucomannan composite hydrogel dressing; the glucomannan composite hydrogel dressing was bonded and compounded with a polyurethane film to obtain a glucomannan composite dressing.

[0031] Example 4

[0032] Step 1: 10 g of glucomannan powder, 3.2 g of a-cellulose powder and 500 g of deionized water were mixed and heated to 50 °C; stirred for 40 min to form a homogeneous sol;

[0033] Step 2: 5 g of aminobeta cyclodextrin powder was added to 370 g of deionized water and sonicated for 20 min; 2.4 g of citric acid and 3.5 g of sodium dihydrogen phosphate were added in 3 portions and reacted at 100 °C for 5-6 h under pressure to obtain a mixed solution, which was cooled and reserved;

[0034] Step 3: 18 g of the homogeneous sol in step 1 was added to 4.1 g of the mixed solution in step 2, 3.6 mg of curcumin was added, and sonicated for 25 min, and then heated to 65 °C and reacted for 2.5 h to obtain a glucomannan composite hydrogel dressing; the glucomannan composite hydrogel dressing was bonded and compounded with a polyurethane film to obtain a glucomannan composite dressing.

[0035] Example 5

[0036] Step 1 : Mix 12 g of glucomannan powder, 3.3 g of a-cellulose powder and 500 g of deionized water, and heat to 55 °C; stir for 35 min to form a uniform sol;

[0037] Step 2: Add 9 g of amino β-cyclodextrin powder to 355 g of deionized water, and ultrasonic for 20 min; add 1.4 g of citric acid and 3.3 g of sodium dihydrogen phosphate in 3 times, and react at 105 °C under pressure for 5.5 h to obtain a mixed solution, cool and reserve;

[0038] Step 3: Add 18 g of the uniform sol in step 1 to 4.2 g of the mixed solution in step 2, add 4 mg of curcumin, heat to 63 °C, and react for 2 h to obtain a glucomannan composite hydrogel dressing; bond and composite the glucomannan composite hydrogel dressing with a polyurethane film to obtain a glucomannan composite dressing patch.

[0039] Example 6

[0040] Step 1 : Mix 15 g of glucomannan powder, 3.4 g of a-cellulose powder and 500 g of deionized water, and heat to 58 °C; stir for 60 min to form a uniform sol;

[0041] Step 2: Add 11 g of amino β-cyclodextrin powder to 360 g of deionized water, and ultrasonic for 18 min; add 1.6 g of citric acid and 3.8 g of sodium dihydrogen phosphate in 3 times, and react at 115 °C under pressure for 5 h to obtain a mixed solution, cool and reserve;

[0042] Step 3: Add 18 g of the uniform sol in step 1 to 4.7 g of the mixed solution in step 2, add 4.9 mg of curcumin, ultrasonic for 25 min, heat to 65 °C, and react for 2 h to obtain a glucomannan composite hydrogel dressing; bond and composite the glucomannan composite hydrogel dressing with a polyurethane film to obtain a glucomannan composite dressing patch.

[0043] Example 7

[0044] Step 1 : Mix 17 g of glucomannan powder, 3 g of a-cellulose powder and 500 g of deionized water, and heat to 50 °C; stir for 60 min to form a uniform sol;

[0045] Step 2: Add 5 g of amino β-cyclodextrin powder to 350 g of deionized water, and ultrasonic for 18 min; add 2.9 g of citric acid and 3.9 g of sodium dihydrogen phosphate in 4 times, and react at 115 °C under pressure for 6 h to obtain a mixed solution, cool and reserve;

[0046] Step 3: 20 g of the uniform sol of step 1 was added to 3 g of the mixed solution described in step 2, 5 mg of curcumin was added, ultrasonic treatment was performed for 27 min, the temperature was raised to 60 °C, and reaction was performed for 2 h to obtain a glucomannan composite hydrogel dressing; the glucomannan composite hydrogel dressing was bonded and compounded with a polyurethane film to obtain a glucomannan composite dressing.

[0047] Example 8

[0048] Step 1: 22 g of glucomannan powder, 4 g of a-cellulose powder and 500 g of deionized water were mixed, and the temperature was raised to 54 °C; stirring was performed for 60 min to form a uniform sol;

[0049] Step 2: 12 g of amino β-cyclodextrin powder was added to 365 g of deionized water, and ultrasonic treatment was performed for 20 min; 3.2 g of citric acid and 3.1 g of sodium dihydrogen phosphate were added in 5 portions, pressure reaction was performed at 100 °C for 5 h to obtain a mixed solution, and the mixed solution was cooled and reserved;

[0050] Step 3: 17 g of the uniform sol of step 1 was added to 4 g of the mixed solution described in step 2, 5 mg of curcumin was added, ultrasonic treatment was performed for 28 min, the temperature was raised to 65 °C, and reaction was performed for 2.8 h to obtain a glucomannan composite hydrogel dressing; the glucomannan composite hydrogel dressing was bonded and compounded with a polyurethane film to obtain a glucomannan composite dressing.

[0051] Example 9

[0052] Step 1: 30 g of glucomannan powder, 3 g of a-cellulose powder and 500 g of deionized water were mixed, and the temperature was raised to 55 °C; stirring was performed for 50 min to form a uniform sol;

[0053] Step 2: 11 g of amino β-cyclodextrin powder was added to 370 g of deionized water, and ultrasonic treatment was performed for 17 min; 2.2 g of citric acid and 3.7 g of sodium dihydrogen phosphate were added in 5 portions, pressure reaction was performed at 100-120 °C for 6 h to obtain a mixed solution, and the mixed solution was cooled and reserved;

[0054] Step 3: 18 g of the uniform sol of step 1 was added to 5 g of the mixed solution described in step 2, 3.3 mg of curcumin was added, ultrasonic treatment was performed for 25 min, the temperature was raised to 70 °C, and reaction was performed for 2 h to obtain a glucomannan composite hydrogel dressing; the glucomannan composite hydrogel dressing was bonded and compounded with a polyurethane film to obtain a glucomannan composite dressing.

[0055] Comparative Example 1

[0056] A glucomannan composite dressing was prepared without adding a-cellulose.

[0057] Step 1 : 10 g of glucomannan powder was mixed with 500 g of deionized water and heated to 50 °C; stirred for 30 min to form a homogeneous sol;

[0058] Step 2: 4 g of aminobeta cyclodextrin powder was added to 350 g of deionized water and ultrasonicated for 15 min; 0.88 g of citric acid and 3 g of sodium dihydrogen phosphate were added in 3 portions and reacted at 100 °C for 5 h to obtain a mixed solution, which was cooled and prepared for use;

[0059] Step 3: 15 g of the homogeneous sol in step 1 was added to 3 g of the mixed solution in step 2, 3 mg of curcumin was added, ultrasonicated for 25 min, heated to 60 °C, and reacted for 2 h to obtain a glucomannan composite hydrogel dressing; the glucomannan composite hydrogel dressing was bonded and compounded with a polyurethane film to obtain a glucomannan composite dressing.

[0060] Comparative Example 2

[0061] β-cyclodextrin was used instead of aminobeta cyclodextrin.

[0062] Step 1 : 20 g of glucomannan powder, 3.5 g of a-cellulose powder and 500 g of deionized water were mixed and heated to 55 °C; stirred for 45 min to form a homogeneous sol;

[0063] Step 2: 8 g of beta cyclodextrin powder was added to 375 g of deionized water, 1.6 g of citric acid and 3.5 g of sodium dihydrogen phosphate were added in 4 portions, and reacted at 110 °C for 5.5 h to obtain a mixed solution, which was cooled and prepared for use;

[0064] Step 3: 18 g of the homogeneous sol in step 1 was added to 4.2 g of the mixed solution in step 2, heated to 65 °C, 4 mg of curcumin was added, ultrasonicated for 30 min, and reacted for 2.5 h to obtain a glucomannan composite hydrogel dressing; the glucomannan composite hydrogel dressing was bonded and compounded with a polyurethane film to obtain a glucomannan composite dressing.

[0065] Comparative Example 3

[0066] Glucomannan composite dressing was prepared without adding beta-cyclodextrin.

[0067] 30 g of glucomannan powder, 4 g of a-cellulose powder and 500 g of deionized water were mixed and heated to 60 °C; stirred for 60 min to form a homogeneous sol; 5 mg of curcumin was added and ultrasonicated for 30 min to obtain a glucomannan composite hydrogel dressing; the glucomannan composite hydrogel dressing was bonded and compounded with a polyurethane film to obtain a glucomannan composite dressing.

[0068] Experiment:

[0069] Tensile strength test: The nanofiber hydrogel samples (3mm in width x 10mm in height) were stretched using a universal testing machine (XQ-1C, New Fiber Instrument, China) at a rate of 40-50mm min -1 , and the tensile mechanical properties were tested. Five parallel samples were measured in each group, and the average value was obtained.

[0070] Adhesion strength test: The adhesion behavior of the hydrogel was tested using a pig skin lap shear test method, and an Instron material testing system (Instron 5565) was used at a tensile rate of 15mm min -1 under a 50N load sensor. The specific method was as follows: the nanofiber hydrogel (3cm x 2cm) was placed between fresh pig skin, and a 200g weight was applied on the sample for 1-3min to ensure close contact. During the measurement, the pig skin lap joint and the pig skin were kept wet, and five parallel samples were measured in each group. The obtained bonding strength was obtained by dividing the load by the bonding area.

[0071] Moisturizing effect test: The dressing was pasted with a polyurethane film, weighed, and placed in a dry constant temperature oven at 20-25℃. The weight was measured every 12h until the weight no longer changed, and the moisturizing time was recorded.

[0072] Moisture absorption rate test: The dressing was pasted with a polyurethane film, weighed and recorded as m0, completely immersed in deionized water for 24h, taken out and wiped off the surface water droplets, weighed and recorded as m1, and the moisture absorption rate = (m1-m0) / m0x100%.

[0073] The experimental results are shown in Table 1.

[0074] Table 1

[0075] Adhesion strength / KPa Tensile strength / MPa Elongation at break / % Moisture retention time / day Moisture absorption rate / % Example 1 Example 2 6.2 4.8 342 6.5 26.6 Example 3 6.7 5.1 318 7 25.3 Example 4 6.1 4.9 322 7 24.8 Example 5 6.3 5.0 327 7.5 29.3 Example 6 6.9 4.9 335 7 21.7 Example 7 6.3 4.6 341 7 27.6 Example 8 6.2 5.1 309 7 24.8 Example 9 6.5 5.2 322 6.5 28.2 Comparative Example 1 6.1 5.0 331 6.5 24.9 Comparative Example 2 8.6 3.1 207 3.5 10.4 Comparative Example 3 6.1 5.1 324 / / ​ 6.6 5.0 326 / /

[0076] Slow-release effect: The nanofiber hydrogel dressings prepared from Examples 2-3 and Comparative Examples 2-3 were placed in PBS solution, and the slow-release of curcumin was monitored at 37℃ (based on the amount of curcumin added when prepared); the experimental results are shown in Table 2.

[0077] Table 2

[0078]

[0079] Conclusion: The present application uses glucomannan as the main raw material to prepare the hydrogel dressing patch. First, the alpha cellulose is compounded with the glucomannan, and the function group -OH on the structure of the alpha cellulose is used to improve the performance of the hydrogel between the hydrogen bond network of the cellulose and the glucomannan. The data of examples 1-9 show that the tensile strength of the hydrogel prepared by the present application is 5.0 MPa, and the elongation at break is more than 300%, which solves the problem of poor mechanical properties of traditional glucomannan hydrogel. In addition, due to the good hydrophilicity of alpha cellulose, the moisture absorption and retention effect of the dressing patch is good. In addition, the alpha cellulose improves the absorbency and moisture retention of the dressing patch, which can absorb wound exudates while maintaining long-term moisturizing.

[0080] With reference to example 1, the data of comparative example 1 shows that the tensile strength of the hydrogel is significantly enhanced after the alpha cellulose is compounded with the glucomannan, which is mainly because the glucomannan molecules can form a hydrogen bond network by hydrogen bond, molecular dipole moment and other intermolecular forces with a large number of water molecules in the aqueous solution, and the structure function group -OH on the cellulose chain is in a flat state, which extends outward along the cellulose molecular structure, so that the hydroxyl group of cellulose can easily obtain hydrogen bond, thereby forming a cross-linked network to enhance the tensile strength of the glucomannan hydrogel. At the same time, the data of comparative example 1 also shows that the adhesion strength of the hydrogel is related to the addition of alpha cellulose. Therefore, the amount of alpha cellulose added needs to be strictly limited. With reference to example 2, the data of comparative example 2 shows that if the beta-cyclodextrin is not modified by amino functionalization, the content of curcumin loaded on the hydrogel is only 28.4% of the added amount of curcumin, which is mainly because most of the curcumin is adsorbed in the cavity of the beta-cyclodextrin, and only a small part of the beta-cyclodextrin adsorbed on the hydrogel. Since the beta-cyclodextrin is not successfully grafted onto the hydrogel, the drug loading amount is reduced. With reference to example 3, the data of comparative example 3 shows that the glucomannan hydrogel has a certain adsorption effect on curcumin, and the drug release speed of the glucomannan hydrogel is faster, and the sustained release effect is not good. It can be found from the data of comparative examples 2-3 that the beta-cyclodextrin and the glucomannan hydrogel have adsorption to curcumin, but the adsorption strength of the beta-cyclodextrin is greater and the adsorption amount is more, so when the beta-cyclodextrin and the glucomannan hydrogel exist at the same time, curcumin will be preferentially adsorbed in the beta-cyclodextrin, so the sustained release effect of the prepared hydrogel is good, and the drug loading rate is high.

[0081] Finally, it should be noted that the above only describes the preferred embodiments of the present application and is not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art will appreciate that the technical solutions described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalent ones. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing a glucomannan-based composite dressing patch, characterized in that: Step 1: glucomannan powder, alpha-cellulose powder and deionized water are mixed, and stirred at elevated temperature to form a uniform sol; the amounts of the components are 10-30 parts by weight of glucomannan powder, 3-4 parts by weight of alpha-cellulose powder, and 500 parts by weight of deionized water; Step 2: amino beta cyclodextrin powder is added to deionized water, and ultrasonic treatment is performed for 15-20 min; citric acid and sodium dihydrogen phosphate are added in 3-5 portions, and a mixed solution is obtained by pressure reaction; the mixed solution is cooled and reserved; Step 3: the uniform sol in Step 1 is added to the mixed solution in Step 2, and curcumin is added; ultrasonic treatment is performed for 25-30 min; the temperature is raised to 60-70℃, and reaction is performed for 2-3 h to obtain a glucomannan composite hydrogel dressing; the glucomannan composite hydrogel dressing is bonded to a carrier to obtain a glucomannan composite dressing patch; the amounts of the components are 15-20 parts by weight of the uniform sol in Step 1, 3-5 parts by weight of the mixed solution in Step 2, and 0.003-0.005 parts by weight of curcumin. In Step 1, the reaction temperature is 50-60℃; the stirring time is 30-60 min; and the stirring speed is 200-500 rpm. In Step 2, the amounts of the components are 4-15 parts by weight of amino beta cyclodextrin powder, 350-400 parts by weight of deionized water, 0.88-3.4 parts by weight of citric acid, and 3-4.2 parts by weight of sodium dihydrogen phosphate. In Step 2, the pressure reaction temperature is 100-120℃, and the reaction time is 5-6 h.

2. A method of preparing a complex dressing patch based on glucomannan according to claim 1, characterized in that: In Step 3, the carrier is any one of a polyurethane film, a polycaprolactone film, a polylactide film, and a polyvinylidene fluoride film.

3. A method of preparing a complex dressing patch based on glucomannan according to claim 1, characterized in that: 6.A composite dressing patch prepared by the method according to any one of claims 1-5.

4. A method of preparing a glycomannan-based composite dressing patch according to claim 1, characterized by: ​ 5. A method of preparing a glycomannan-based composite dressing patch according to claim 1, characterized by: ​ ​

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