Application of spontaneous heating Janus membrane based on polyvinyl alcohol-polyurethane to healing of diabetic ulcerative wounds
Patent Information
- Application Number
- CN202411290106.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-14
- Publication Date
- 2024-12-17
AI Technical Summary
The healing of diabetic wounds is limited by the problems of excessive exudate and reduced temperature. The prior art is difficult to effectively solve the exudate removal and temperature regulation, resulting in delayed healing and increased risk of bacterial infection.
The self-heating Janus film was prepared by electrospinning technology. By spinning the polyvinyl alcohol layer on the polyurethane layer, potting iron powder, activated carbon powder and sodium chloride, the water and oxygen in the exudate triggered the oxidation and release of heat from the iron powder. , realize the dual functions of self-heating and permeability, and promote wound healing.
Self-heating Janus membrane can actively absorb wound exudate, increase wound temperature, enhance cell metabolism and blood flow regulation, significantly accelerate wound healing, avoid the risk of low-temperature scalding, and is better than the effect of simple Janus membrane.
Smart Images
Figure CN119139526A_ABST
Abstract
Description
Technical field:
[0001] The invention relates to a self-heating Janus membrane prepared from polyvinyl alcohol and polyurethane by electrostatic spinning technology and used for promoting the healing of diabetic wounds. Technical background:
[0002] The name of Janus membrane comes from Janus, the two-faced god in ancient Roman mythology. In 1991, Gennes first proposed the term Janus to describe particles with different compositions or properties on both sides. Janus membrane is the most studied and widely used part of Janus materials. Its asymmetric wettability is widely used in various fields such as directional transmission of fluids, oil-water separation, mist collection, membrane distillation, etc. This article studies wound dressings based on the asymmetric wettability of Janus membranes.
[0003] The asymmetric structure of the Janus membrane can control the wetting and transport behavior of the liquid by adjusting the gas / liquid / solid interface. This asymmetric wettability structure can transfer biological fluids from the hydrophobic layer to the hydrophilic layer, thereby achieving unidirectional permeability removal of wound exudate. This asymmetric wettability is used in a variety of two-phase processes. The asymmetric manufacturing method used in the Janus membrane of the present invention is to directly generate another layer of membrane on the surface of the membrane after one layer of membrane is prepared. This operation is completed by electrospinning technology.
[0004] The self-heating Janus membrane of the present invention is prepared from hydrophilic polyvinyl alcohol (PVA) and hydrophobic polyurethane (PU). Polyvinyl alcohol has good film-forming properties and biocompatibility, and the polyhydroxy structure of the side chain makes it have good hydrophilicity, but it may cause it to dissolve quickly in tissue exudate, so it needs to be modified to enhance the water resistance of the material. Glutaraldehyde is used as a cross-linking agent for polyvinyl alcohol electrospun nanofibers, which can significantly improve the water resistance, thermal stability, mechanical stability, tensile strength and elongation at break of polyvinyl alcohol nanofibers.
[0005] The self-heating Janus membrane of the present invention is based on the self-heating principle of the commercially available "warm baby". Iron powder, activated carbon powder and sodium chloride are encapsulated in the Janus membrane. Unlike the "warm baby", the self-heating Janus membrane of the present invention lacks water, while the "warm baby" lacks oxygen. When the tissue exudate enters the polyethylene layer from the polyurethane layer through the unidirectional permeability of the Janus membrane, the water therein acts together with the sodium chloride and oxygen to trigger the oxidation of the iron powder to release heat. The oxidation reaction process will continue to consume the water content of the exudate, so that the water absorption of the Janus membrane will not reach saturation, and the liquid can be continuously absorbed and the reaction can be promoted to complete.
[0006] Studies have shown that temperature plays a vital role in the wound healing process. Maintaining a suitable temperature is conducive to promoting wound healing. Temperature affects physiological processes including cell metabolism and blood flow regulation. A slightly elevated temperature within the physiological range can promote the wound healing process. The self-heating Janus membrane of the present invention can absorb wound exudate unidirectionally, trigger iron powder oxidation to release heat, improve the wound microenvironment while increasing the wound surface temperature, and promote rapid wound healing. Summary of the invention:
[0007] The invention relates to a self-heating Janus membrane prepared by polyvinyl alcohol and polyurethane through electrostatic spinning technology and used for promoting the healing of diabetic wounds.
[0008] The Janus membrane is manufactured by an asymmetric method. After the polyurethane fiber membrane is prepared, polyvinyl alcohol fiber membrane is directly spun again on its surface, and then self-heating materials including iron powder, activated carbon powder and sodium chloride are encapsulated in the Janus membrane by hot pressing technology to prepare the self-heating Janus membrane.
[0009] The film-forming materials required for the Janus membrane are polyurethane and polyvinyl alcohol. The required polyurethane solution is characterized in that the solvent of the polyurethane solution is a mixed solvent of tetrahydrofuran and N,N-dimethylformamide in a volume ratio of 1:1, the polyurethane is stirred and dissolved under heating at 60°C, ultrasonically degassed for 30 minutes and then cooled to room temperature, and the concentration is 12-18% (w / v); the required polyvinyl alcohol solution is characterized in that the solvent of the polyvinyl alcohol solution is water, the polyvinyl alcohol is stirred and dissolved under heating at 80°C, ultrasonically degassed for 30 minutes and then cooled to room temperature, and the concentration is 10% (w / v).
[0010] The preparation method of the Janus membrane is electrostatic spinning technology, and its characteristic parameters are that the electrostatic spinning time of the polyurethane fiber membrane is 1-2h, the voltage is 5.87-9.87KV, and the liquid flow rate is 0.15-0.2mL / min; the electrostatic spinning time of the polyvinyl alcohol fiber membrane is 1h, the voltage is 17.78KV, and the liquid flow rate is 0.10mL / min. The Janus membrane is prepared by electrostatic spinning technology, characterized in that the fiber membrane with a polyurethane-polyvinyl alcohol double-layer structure needs to be cross-linked and cured for 24h using 20mL glutaraldehyde and 1mL trifluoroacetic acid, and then evaporated to remove the residual organic solvent.
[0011] The heating material encapsulated by the self-heating Janus membrane includes iron powder, activated carbon powder and sodium chloride, and its characteristic parameters are that the mass of the iron powder is 0.35-0.55g, the mass of the activated carbon powder is 0.20-0.30g, the mass of the sodium chloride is 0.03-0.07g, and the mass ratio of Fe:C:NaCl is 9:6:0.6.
[0012] The self-heating Janus membrane encapsulating the self-heating material adopts the hot pressing sealing technology, after the hydrophobic polyurethane layer of the Janus membrane is folded in half on the outside, the two sides of the edge are hot pressed and sealed, and the self-heating material is poured in to completely seal the opening, and its characteristic parameters are temperature 80-120°C and time 5s.
[0013] The self-heating Janus membrane prepared by hot-pressing and encapsulating the self-heating material in the Janus membrane has a better promoting effect on wound healing than the simple Janus membrane.
[0014] Diabetic foot ulcer
[0015] Diabetes is a major global health issue with an increasing prevalence. In 2021, 1 in 10 adults (20-79 years old) worldwide, or 537 million people, will be affected by diabetes, and approximately 6.3% of diabetic patients worldwide suffer from diabetic foot ulcers (DFU). Studies have shown that maintaining optimal temperature is essential for promoting wound healing because it affects various physiological processes, including cell metabolism and blood flow regulation. In chronic uninfected wounds, the wound surface temperature will drop by 30.20°C to 33.00°C, with an average of 31.60°C. 33°C is the critical temperature for reduced activity of neutrophils, fibroblasts, and epithelial cells in the in vitro environment. At the same time, chronic diabetic ulcer wounds are usually manifested by increased exudate, and excessive exudate may affect the efficacy of drugs, resulting in delayed wound healing and aggravated bacterial infection. The self-heating Janus membrane of the present invention can actively absorb wound exudate and introduce moisture into the self-heating material through unidirectional permeability, triggering the oxidation of iron powder and releasing heat, thereby increasing the temperature of the wound surface and promoting the healing process of the wound.
[0016] Beneficial effects:
[0017] The present invention discloses a self-heating Janus membrane wound dressing prepared by electrostatic spinning technology, which uses hydrophilic polyvinyl alcohol and hydrophobic polyurethane as raw materials, has the dual functions of keeping wounds dry and releasing heat, and synergistically promotes wound healing.
[0018] 1. Using the unidirectional permeability of the Janus membrane, wound exudate is introduced into the self-heating system to trigger iron powder oxidation and heat release. The usual self-heating system is controlled by oxygen, while the self-heating system of the present invention is controlled by the water in the exudate, avoiding low-temperature burns caused by excessive heat generation time.
[0019] 2. The self-heating Janus membrane has the dual effects of drainage and heat generation, synergistically promoting wound healing. Description of the drawings:
[0020] Figure 1This is the application of the diabetes control group, Example 1, and Example 2 in treating diabetic ulcer wounds. Specific implementation method:
[0021] Example 1: Preparation of Jauns film based on polyurethane-polyvinyl alcohol
[0022] A certain amount of polyurethane was stirred and dissolved in a mixed solvent of tetrahydrofuran and N,N-dimethylformamide in a volume ratio of 1:1 under heating at 60°C, and a certain amount of polyvinyl alcohol was stirred and dissolved in water under heating at 80°C. Both solutions were ultrasonically degassed for 30 minutes and then cooled to room temperature. Polyurethane was first spun using an electrospinning machine to obtain a hydrophobic polyurethane film, and polyvinyl alcohol was further spun onto the polyurethane film to obtain a Jauns film. The Jauns film was then cross-linked and cured with glutaraldehyde and trifluoroacetic acid for 24 hours, and the residual organic solvent was evaporated to remove it.
[0023] Example 2: Preparation of self-heating Jauns film based on polyurethane-polyvinyl alcohol
[0024] The hydrophobic polyurethane layer of the Jauns film prepared in Example 1 was folded in half on the outside, and the two sides of the edges were sealed by hot pressing at a certain temperature for 5 seconds. Iron powder, activated carbon powder and sodium chloride were poured in a mass ratio of 9:6:0.6 and then hot pressed again to completely seal, so as to obtain a self-heating Jauns film.
[0025] Example 3: In vivo evaluation of treating diabetic wounds
[0026] A wound model of diabetic mice was established. Male Balb / C mice aged 4-6 weeks were fed with a high-sugar and high-fat diet for 4 weeks, and then intraperitoneally injected with streptozotocin (55 mg / kg) citrate buffer solution for 5 consecutive days. Mice with blood glucose levels >16.7 mmol / L were considered to have successfully established a diabetic model. The successfully modeled diabetic mice were selected for intraperitoneal injection of chloral hydrate anesthesia, and the dorsal hair was shaved. Then, a circular full-thickness skin wound with a diameter of 8 mm was formed by a biopsy punch, and a silicone gasket was sutured around the wound with non-absorbable sutures to prevent skin adhesion and contraction. The experimental mice were randomly divided into 3 groups: a diabetic control group, Example 1 group, and Example 2 group. All experimental groups took pictures of the wounds on days 0, 3, 7, and 10, and the wound healing rate was evaluated by ImageJ software.
[0027] The results are as follows Figure 1As shown in the figure, compared with the diabetic control group, both the Jauns membrane and the self-heating Jauns membrane can effectively treat diabetic ulcer wounds and promote the healing of wounds. The self-heating Jauns membrane has a more obvious effect on promoting wound healing than the Jauns membrane, mainly because the fiber membrane itself can actively absorb wound exudate and improve the wound microenvironment, while the self-heating Jauns membrane can also increase the temperature of the wound surface. The dual effects significantly improve cell metabolism and blood flow regulation, accelerating wound healing.
Claims
1. The role of polyvinyl alcohol-polyurethane self-heating Janus membrane prepared by electrospinning technology in promoting the healing of diabetic ulcerative wounds.
2. The use according to claim 1, characterized in that: Janus membrane is used to promote the healing of superficial chronic wounds.
3. The use according to any one of claims 1-2, characterized in that: The surface chronic wounds include diabetic ulcerative wounds.
4. The use according to any one of claims 1 to 3, characterized in that: The Janus membrane was prepared by electrospinning technology, and the preparation parameters of the polyurethane fiber membrane were set as spinning time 1-2h, voltage 5.87-9.87KV, and flow rate 0.15-0.2mL / min.
5. The use according to any one of claims 1 to 4, characterized in that: The Janus membrane was prepared using electrospinning technology, and the preparation parameters of the polyvinyl alcohol fiber membrane were set as spinning time 1 h, voltage 17.78 KV, and liquid flow rate 0.10 mL / min.
6. The use according to any one of claims 1 to 5, characterized in that: The film-forming materials of Janus membrane are polyvinyl alcohol and polyurethane.
7. The use according to any one of claims 1 to 6, characterized in that: The solvent of polyvinyl alcohol is water with a concentration of 10%; the solvent of polyurethane is tetrahydrofuran and N,N-dimethylformamide with a volume ratio of 1:1 and a concentration of 12-18 (15)%.
8. The use according to any one of claims 1 to 7, characterized in that: The Janus membrane prepared by the invention is a self-heating wound dressing, and the self-heating materials include iron powder, activated carbon powder and sodium chloride.
9. The use according to any one of claims 1 to 8, characterized in that: The amount of iron powder used is 0.35-0.55 g, the amount of activated carbon powder used is 0.20-0.30 g, the amount of sodium chloride used is 0.03-0.07 g, and the mass ratio of Fe:C:NaCl is 9:6:0.
6.
10. The use according to any one of claims 1 to 9, characterized in that: The Janus membrane encapsulated self-heating material adopts a hot pressing process, and the hot pressing conditions are a temperature of 80-120°C and a time of 5s.
11. The use according to any one of claims 1 to 10, characterized in that: The Janus membrane preparation method is characterized in that polyurethane is firstly formed into a fiber membrane through electrostatic spinning technology, and then polyvinyl alcohol is spun and fused again on the surface of the fiber membrane to form a polyvinyl alcohol-polyurethane composite membrane.
12. The use according to any one of claims 1 to 11, characterized in that: After the Janus membrane was synthesized, glutaraldehyde and trifluoroacetic acid were used for cross-linking and curing for 24 h, and the cross-linking agent was evaporated to remove.
13. The use according to any one of claims 1 to 12, characterized in that: The preparation method of the self-heating Janus membrane is characterized in that the hydrophobic polyurethane layer of the Janus membrane is folded in half on the outside, the two sides of the edge are heat-pressed and sealed, the self-heating material is poured in, and then heat-pressed again to completely seal.