A dressing for relieving pain and promoting healing of burn wounds and a method of preparation

Abstract

The application provides a dressing for relieving pain and promoting healing of burn wounds and a preparation method. The dressing for relieving pain and promoting healing of burn wounds is composed of the following components in mass percentage: 8-10% of gelatin, 3-5% of sodium carboxymethyl cellulose, 0.1-0.3% of ferric chloride, 0.5-1% of dopamine, 0.15-0.25% of cannabidiol, 0.3-0.5% of 2-propanol, 0.05-0.1% of polylysine hydrochloride, 0.04-0.06% of vitamin E, 2-3% of trehalose and the rest of phosphate buffer. The dressing can obtain excellent effect of relieving pain and promoting healing of burn wounds through the synergistic cooperation of the components.

Description

Technical Field

[0001] This invention belongs to the field of wound care technology, specifically relating to a dressing that helps relieve pain and promote healing of burn wounds and its preparation method. Background Technology

[0002] In the field of burn treatment, choosing the right dressing is crucial for wound healing and patient recovery. Currently, there are many types of burn dressings commonly used in clinical practice, each with its own characteristics and limitations.

[0003] Traditional gauze dressings are a common type, offering advantages such as simple manufacturing, low cost, and good absorbency, providing some protection to the wound and thus still widely used in many primary care hospitals. However, gauze dressings have significant drawbacks. They cannot maintain a moist environment in the wound, delaying healing. Furthermore, the fibers are prone to shedding, which can cause a foreign body reaction and interfere with the normal healing process. During dressing changes, granulation tissue can grow into the gauze mesh, damaging the granulation tissue, affecting healing, and causing intense pain for the patient. Moreover, when the gauze becomes soaked, pathogens can easily pass through, greatly increasing the risk of wound infection, and frequent dressing changes increase the workload of medical staff.

[0004] Biological dressings, such as allogeneic or xenogeneic skin, are widely used in the early treatment of large-area burns. They have strong adhesion, provide excellent barrier protection, and possess hemostatic properties, which can alleviate patient pain to some extent. They can be used at donor sites, superficial second-degree burns, or deep second- to third-degree burns after escharotomy. However, the source of allogeneic skin is extremely limited, and there is a potential risk of transmitting bacterial, fungal, and viral diseases. Xenogeneic skin (such as pigskin or sheepskin) has poor elasticity, the epidermis is prone to shedding, its resistance to infection is relatively weak, and it is also antigenic, which can cause receptor immune rejection, thus limiting the time it can cover the wound.

[0005] Synthetic dressings are made from polymer materials and come in various types, including film-type, foam-type, spray-type, and composite-type. Film-type synthetic dressings generally consist of two layers: an inner hydrophilic material that absorbs wound exudate, and an outer material with good breathability and elasticity. They are transparent, facilitating wound observation, and can also absorb some exudate. However, once saturated, these dressings can easily accumulate exudate under the film, potentially promoting pathogen growth and worsening wound infection. Therefore, they are not suitable for exudative or infected wounds. Summary of the Invention

[0006] The purpose of this invention is to provide a dressing that can effectively relieve pain and promote the healing of burn wounds, in order to solve the problems of existing burn dressings being ineffective in relieving pain and promoting healing, as well as being prone to infection and causing severe scarring.

[0007] Beneficial effects

[0008] The cannabidiol in this invention's dressing regulates the body's endocannabinoid system, acting on corresponding receptors on nerve cells to inhibit pain signal transmission, thereby exerting significant anti-inflammatory and analgesic effects and effectively reducing patient suffering. 2-Cetyl alcohol acts directly on nerve endings in the wound, altering nerve cell membrane permeability and preventing the generation and transmission of pain signals, producing a rapid local anesthetic and analgesic effect. The two work synergistically, acting through different mechanisms to provide patients with a more comprehensive and effective analgesic effect, offering faster and more significant relief from burn pain compared to traditional dressings.

[0009] In promoting wound healing, multiple components in the dressing work synergistically. Gelatin and sodium carboxymethyl cellulose create a moist healing environment that meets the needs of cell growth and proliferation, accelerating epidermal cell migration and proliferation, and promoting wound epithelialization. Dopamine promotes the migration and proliferation of fibroblasts and epithelial cells, helping to synthesize new extracellular matrix and collagen, building new tissue structure. Vitamin E promotes collagen synthesis, enhancing skin elasticity and resilience, and reducing scar formation. Polylysine hydrochloride effectively inhibits bacterial growth, prevents wound infection, and creates a favorable environment for wound healing. Trehalose maintains wound moisture, stabilizes cell structure, and protects cells from damage. These components work together to comprehensively promote burn wound healing, not only accelerating the healing process but also improving healing quality, reducing scar formation, and minimizing the physical and psychological impact of burns on patients. Detailed Implementation

[0010] An embodiment of the present invention provides a dressing that facilitates pain relief and promotes healing of burn wounds, characterized in that it comprises the following components in the indicated weight percentages: 8-10% gelatin, 3-5% sodium carboxymethyl cellulose, 0.1-0.3% ferric chloride, 0.5-1% dopamine, 0.15-0.25% cannabidiol, 0.3-0.5% 2-carboxyol, 0.05-0.1% polylysine hydrochloride, 0.04-0.06% vitamin E, 2-3% trehalose, and the balance being phosphate buffer.

[0011] The cannabidiol in this invention's dressing regulates the body's endocannabinoid system, acting on corresponding receptors on nerve cells to inhibit pain signal transmission, thereby exerting significant anti-inflammatory and analgesic effects and effectively reducing patient suffering. 2-Cetyl alcohol acts directly on nerve endings in the wound, altering nerve cell membrane permeability and preventing the generation and transmission of pain signals, producing a rapid local anesthetic and analgesic effect. The two work synergistically, acting through different mechanisms to provide patients with a more comprehensive and effective analgesic effect, offering faster and more significant relief from burn pain compared to traditional dressings.

[0012] In promoting wound healing, multiple components in the dressing work synergistically. Gelatin and sodium carboxymethyl cellulose create a moist healing environment that meets the needs of cell growth and proliferation, accelerating epidermal cell migration and proliferation, and promoting wound epithelialization. Dopamine promotes the migration and proliferation of fibroblasts and epithelial cells, helping to synthesize new extracellular matrix and collagen, building new tissue structure. Vitamin E promotes collagen synthesis, enhancing skin elasticity and resilience, and reducing scar formation. Polylysine hydrochloride effectively inhibits bacterial growth, prevents wound infection, and creates a favorable environment for wound healing. Trehalose maintains wound moisture, stabilizes cell structure, and protects cells from damage. These components work together to comprehensively promote burn wound healing, not only accelerating the healing process but also improving healing quality, reducing scar formation, and minimizing the physical and psychological impact of burns on patients.

[0013] Gelatin and sodium carboxymethyl cellulose (CMC) serve as the base matrix components. Gelatin possesses excellent biocompatibility, providing a gentle environment for the wound and reducing external irritation. Its three-dimensional network structure also acts as a scaffold for cell growth, promoting cell adhesion and proliferation. CMC forms a gel upon contact with exudate, adhering firmly to the wound surface and locking in moisture, creating a moist healing environment that aligns with the theory of moist wound healing. This effectively promotes wound healing and reduces scar formation. Furthermore, the gel-like structure formed by both components creates a physical barrier on the wound surface, preventing the invasion of bacteria and other pathogens.

[0014] The iron ions in ferric chloride can undergo a complexation reaction with dopamine to form a polydopamine-ferric ion complex with adhesive and antioxidant properties. This complex enhances the adhesion between the dressing and the wound, making it adhere more tightly to the wound and less prone to falling off. At the same time, the antioxidant properties can effectively eliminate free radicals generated on the wound surface, reduce oxidative stress damage to tissues, protect wound cells, and promote wound healing.

[0015] Dopamine not only participates in the formation of polydopamine-iron complexes but also promotes cell migration and proliferation. During burn wound healing, it can stimulate the migration and proliferation of fibroblasts and epithelial cells, accelerating wound repair. Cannabidiol possesses excellent anti-inflammatory and analgesic properties, effectively inhibiting inflammatory responses and reducing symptoms such as redness, swelling, and pain in burn wounds. By regulating the activity of inflammatory cells and the release of inflammatory mediators, cannabidiol can create a microenvironment conducive to wound healing, reducing the hindering effect of inflammation on wound healing.

[0016] 2-Citrol has a local anesthetic effect, acting directly on nerve endings in the wound to reduce their sensitivity and thus quickly relieve burn pain. Polylysine hydrochloride is a cationic antibacterial agent that effectively inhibits various common pathogens, including Gram-positive and Gram-negative bacteria, effectively preventing and controlling wound infection and providing a clean environment for wound healing.

[0017] Vitamin E is a powerful antioxidant that can further eliminate free radicals in wounds, protect cell membrane integrity, reduce cell damage, and promote collagen synthesis, helping to enhance skin elasticity and resilience after wound healing and reduce scar formation. Trehalose has excellent moisturizing and stability properties; it can form a protective film on the wound surface to prevent excessive moisture loss, maintain wound moisture, and stabilize protein and cell membrane structure, protecting cells from damage and providing favorable conditions for wound healing.

[0018] Phosphate buffer is used to maintain the pH stability of the dressing, providing a suitable acid-base environment for each component to function, and ensuring the stability and effectiveness of the entire dressing system. Through the synergistic effect of each component, the dressing of the present invention can play a role in multiple aspects such as pain relief, anti-infection, promoting cell proliferation and migration, and anti-oxidation, thereby achieving excellent effects in relieving pain and promoting healing of burn wounds.

[0019] In some embodiments, the gelatin is animal bone gelatin with a purity of not less than 95%. Compared to gelatin from other sources, animal bone gelatin has better biocompatibility and stability, providing a gentler and more stable environment for the wound. High-purity gelatin contains fewer impurities, reducing the potential irritation of impurities to the wound and further enhancing its role as a base matrix component in dressings. This helps promote cell adhesion and proliferation, thus better achieving the effect of promoting wound healing.

[0020] In some embodiments, sodium carboxymethyl cellulose has a degree of substitution of 0.6-0.8 and a molecular weight of 200,000-300,000. Sodium carboxymethyl cellulose with specific degrees of substitution and molecular weight exhibits superior gel-forming properties upon contact with exudate, enabling it to adhere more effectively to the wound surface, providing better water retention and creating a more ideal moist healing environment. Simultaneously, this property enhances its synergistic effect with other components, improving the overall performance of the dressing, promoting wound healing, and reducing scar formation.

[0021] In some embodiments, the ferric chloride particles have a particle size of 50-100 nm. A suitable particle size allows for a more complete complexation reaction with dopamine, forming a superior polydopamine-ferric ion complex. This complex not only enhances the adhesion between the dressing and the wound, making it adhere more tightly and less prone to falling off, but also improves its antioxidant properties, more effectively scavenging free radicals generated in the wound, reducing oxidative stress damage to tissues, thereby better protecting wound cells and promoting wound healing.

[0022] In some embodiments, the dopamine is L-dopamine. L-dopamine exhibits higher bioactivity and stability compared to other forms of dopamine. During burn wound healing, it can more effectively stimulate the migration and proliferation of fibroblasts and epithelial cells, accelerating wound repair. Furthermore, L-dopamine has better compatibility with other components, allowing it to better fulfill its role in dressings and further promote wound healing.

[0023] In some embodiments, the optical purity of 2-Citrol is not less than 99%. High-purity 2-Citrol has a stronger local anesthetic effect, acting more quickly and effectively on nerve endings in the wound, reducing nerve ending sensitivity, and thus rapidly relieving burn pain. Simultaneously, high-purity 2-Citrol has better stability, allowing it to exert its analgesic effect more stably in dressings, providing patients with more timely and longer-lasting pain relief.

[0024] In some embodiments, the purity of cannabidiol is not less than 98%. Higher purity cannabidiol contains fewer impurities, allowing its anti-inflammatory and analgesic properties to be more fully realized. It can more effectively inhibit inflammatory responses, reduce redness, swelling, and pain in burn wounds, regulate the activity of inflammatory cells and the release of inflammatory mediators, create a more favorable microenvironment for wound healing, and reduce the hindering effect of inflammation on wound healing, thereby better achieving analgesic and healing-promoting effects.

[0025] In some embodiments, the degree of polymerization of polylysine hydrochloride is 10-15. Polylysine hydrochloride with a specific degree of polymerization exhibits more suitable antibacterial activity and stability. It maintains good inhibitory effects against a variety of common pathogens, including Gram-positive and Gram-negative bacteria, effectively preventing and controlling wound infection and providing a clean environment for wound healing. Simultaneously, this degree of polymerization makes its interaction with other components more coordinated, which is beneficial for improving the overall performance of the dressing.

[0026] In some embodiments, the pH of the phosphate buffer is 7.2-7.4. A phosphate buffer with a specific pH value can more stably maintain the acid-base environment of the dressing, providing more suitable conditions for each component to function, ensuring the stability and effectiveness of the entire dressing system, and thus more comprehensively promoting pain relief and healing of burn wounds.

[0027] In some embodiments, trehalose is anhydrous trehalose. Anhydrous trehalose has stronger moisturizing and stability properties, enabling it to form a more effective protective film on the wound surface, preventing excessive moisture loss, maintaining the wound's moisture level, and better protecting cells from damage.

[0028] Another embodiment of the present invention provides a method for preparing the above-mentioned dressing that is beneficial for relieving pain and promoting healing of burn wounds, comprising the following steps:

[0029] At 25°C, add gelatin to phosphate buffer and stir at a low speed of 150 r / min for 30 min to allow the gelatin to fully swell.

[0030] Next, sodium carboxymethyl cellulose was added, and the stirring speed was increased to 250 r / min. Stirring was continued for 45 min to ensure that the sodium carboxymethyl cellulose and gelatin solution were fully mixed to obtain a mixture.

[0031] Add ferric chloride to the mixture and simultaneously adjust the stirring speed to 300 r / min and stir for 1 hour to ensure that the ferric chloride is evenly dispersed.

[0032] Subsequently, dopamine was added, and the stirring speed was maintained at 300 r / min for 2 h to allow dopamine and ferric chloride to undergo a complexation reaction and form a polydopamine-ferric ion complex.

[0033] Then, add cannabidiol, 2-Citrol, polylysine hydrochloride, vitamin E and trehalose in sequence. After each addition, stir at 200 r / min for 30 min to ensure that all components are fully mixed and homogeneous, and obtain the pre-finished product.

[0034] The pre-finished product is poured into a mold for shaping, and then vacuum dried at a temperature of 40℃, a vacuum degree of 0.08MPa, and a drying time of 6 hours.

[0035] After drying, the product is sterilized by gamma irradiation at a dose of 25 kGy.

[0036] The following are examples and comparative examples.

[0037] Example 1

[0038] In this embodiment, the dressing consists of the following components by weight percentage: 8% gelatin (animal bone gelatin, 96% purity), 3% sodium carboxymethyl cellulose (degree of substitution 0.7, molecular weight approximately 220,000), 0.1% ferric chloride (particle size 60 nm), 0.5% dopamine (L-dopamine), 0.15% cannabidiol (98% purity), 0.3% 2-Cetyl alcohol (99% optical purity), 0.05% polylysine hydrochloride (degree of polymerization 12), 0.04% vitamin E (natural vitamin E), 2% trehalose (anhydrous trehalose), and the balance being phosphate buffer (pH 7.3).

[0039] The preparation method of the dressing is as follows:

[0040] At 25°C, gelatin was added to phosphate buffer and stirred at a low speed of 150 r / min for 30 min to allow the gelatin to fully swell.

[0041] Next, add sodium carboxymethyl cellulose, increase the stirring speed to 250 r / min, and continue stirring for 45 min to fully mix the sodium carboxymethyl cellulose with the gelatin solution to obtain a mixture;

[0042] Add ferric chloride to the mixture and simultaneously adjust the stirring speed to 300 r / min and stir for 1 hour to ensure that the ferric chloride is evenly dispersed.

[0043] Subsequently, dopamine was added, and the stirring speed was maintained at 300 r / min for 2 h to allow dopamine to fully undergo a complexation reaction with ferric chloride to form a polydopamine-ferric ion complex.

[0044] Then, add cannabidiol, 2-Citrol, polylysine hydrochloride, vitamin E and trehalose in sequence. After each addition, stir at 200 r / min for 30 min to ensure that all components are fully mixed and homogeneous to obtain the pre-finished product.

[0045] The pre-finished product is poured into a mold for shaping, and then vacuum dried at a temperature of 40℃, a vacuum degree of 0.08MPa, and a drying time of 6 hours.

[0046] After drying, the product is sterilized by gamma irradiation at a dose of 25 kGy.

[0047] Example 2

[0048] Compared with Example 1, the difference is that the dressing is composed of the following components in the following mass percentages: 9% gelatin, 4% sodium carboxymethyl cellulose, 0.2% ferric chloride, 0.8% dopamine, 0.2% cannabidiol, 0.4% 2-carboxyol, 0.08% polylysine hydrochloride, 0.05% vitamin E, 2.5% trehalose, and the balance being phosphate buffer.

[0049] Example 3

[0050] Compared with Example 1, the difference is that the dressing is composed of the following components in the following mass percentages: 10% gelatin, 5% sodium carboxymethyl cellulose, 0.3% ferric chloride, 1% dopamine, 0.25% cannabidiol, 0.5% 2-carboxyol, 0.1% polylysine hydrochloride, 0.06% vitamin E, 3% trehalose, and the balance being phosphate buffer.

[0051] Comparative Example 1

[0052] The difference compared to Example 1 is that it does not contain cannabidiol.

[0053] Comparative Example 2

[0054] The difference compared to Example 1 is that it does not contain dopamine.

[0055] Comparative Example 3

[0056] The difference compared to Example 1 is that it does not contain ferric chloride.

[0057] Comparative Example 4

[0058] Compared with Example 1, the difference is that the dressing is composed of the following components in the following mass percentages: 6% gelatin, 2% sodium carboxymethyl cellulose, 0.5% ferric chloride, 1.5% dopamine, 0.4% cannabidiol, 0.8% 2-carboxyol, 0.3% polylysine hydrochloride, 0.1% vitamin E, 5% trehalose, and the balance being phosphate buffer.

[0059] Test case

[0060] (1) Analgesic effect

[0061] Healthy adult rats were selected, and a burn model was created using the hot water immersion method. A specific area of ​​skin on the rat's back was immersed in 80°C hot water for 10 seconds, causing superficial second-degree burns. The rats were randomly divided into 7 groups: the example group and the comparative group, with 10 rats in each group. Immediately after the burns, dressings prepared for the example and comparative groups were applied to the burn wounds of the rats. Six hours after treatment, the rats' pain levels were assessed by professionals using the Visual Analogue Scale (VAS) under the same environmental and time conditions. A score of 0 indicated no pain, and a score of 10 indicated severe pain. The average value of each group was taken as the test result for that group.

[0062] (2) Wound healing time

[0063] From the time the wound is created, observe the wound healing process daily and record the time it takes for the wound to fully heal (the epidermis completely covers the wound). Take the average value of each group as the test result for that group.

[0064] (3) Scar area

[0065] After administration of the drug to the wound, the scar area at the burn site was measured on day 14 after healing. The average value of each group was taken as the test result for that group.

[0066] (4) Cytotoxicity

[0067] Prepare dressing extract (1g sample + 10mL culture medium, extract at 37℃ for 24h).

[0068] Co-cultured with L929 cells for 48 hours, then MTT solution (5 mg / mL) was added, and cultured for another 4 hours.

[0069] Measure the absorbance at 570 nm and calculate the cell viability: (sample group absorbance / blank group absorbance) × 100%. Take the average value of each group as the test result for that group.

[0070] The test results are shown in the table below.

[0071]

[0072] The results above show that the dressing of the present invention can effectively relieve burn wound pain and promote wound healing.

[0073] 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, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0074] For those skilled in the art, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A method for preparing a dressing that facilitates pain relief and promotes healing of burn wounds, characterized in that, The dressing is composed of the following components in the indicated weight percentages: 8-10% gelatin, 3-5% sodium carboxymethyl cellulose, 0.1-0.3% ferric chloride, 0.5-1% levodopa, 0.15-0.25% cannabidiol, 0.3-0.5% 2-carboxylic acid, 0.05-0.1% polylysine hydrochloride, 0.04-0.06% vitamin E, 2-3% trehalose, and the balance being phosphate buffer; the ferric chloride has a particle size of 50-100 nm. The preparation method of the dressing is as follows: At 25°C, gelatin was added to phosphate buffer and stirred at a low speed of 150 r / min for 30 min to allow the gelatin to fully swell. Next, add sodium carboxymethyl cellulose, increase the stirring speed to 250 r / min, and continue stirring for 45 min to fully mix the sodium carboxymethyl cellulose with the gelatin solution to obtain a mixture; Add ferric chloride to the mixture and simultaneously adjust the stirring speed to 300 r / min and stir for 1 hour to ensure that the ferric chloride is evenly dispersed. Subsequently, L-dopamine was added, and the stirring speed was maintained at 300 r / min for 2 h to allow L-dopamine to fully undergo a complexation reaction with ferric chloride to form a polydopamine-ferric ion complex. Then, add cannabidiol, 2-Citrol, polylysine hydrochloride, vitamin E and trehalose in sequence. After each addition, stir at 200 r / min for 30 min to ensure that all components are fully mixed and homogeneous to obtain the pre-finished product. The pre-finished product is poured into a mold for shaping, and then vacuum dried at a temperature of 40℃, a vacuum degree of 0.08MPa, and a drying time of 6 hours. After drying, the product is sterilized by gamma irradiation at a dose of 25 kGy.

2. The preparation method according to claim 1, characterized in that, The gelatin is animal bone gelatin with a purity of not less than 95%.

3. The preparation method according to claim 1, characterized in that, The sodium carboxymethyl cellulose has a degree of substitution of 0.6-0.8 and a molecular weight of 200,000-300,000.

4. The preparation method according to claim 1, characterized in that, The optical purity of the 2-coke is not less than 99%.

5. The preparation method according to claim 1, characterized in that, The degree of polymerization of the polylysine hydrochloride is 10-15.

6. The preparation method according to any one of claims 1-5, characterized in that, The pH value of the phosphate buffer is 7.2-7.

4.

7. The preparation method according to any one of claims 1-5, characterized in that, The trehalose mentioned is anhydrous trehalose.

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