An accelerated wound healing dressing, method of manufacture and use

Abstract

A wound healing accelerating dressing, its preparation method, and its application belong to the field of functional composite materials. The wound dressing comprises a double-layer structure; the upper layer is an antibacterial adhesive film, prepared by a solution reaction of raw materials including the following components: isophorone diisocyanate, triphenylmethane triisocyanate, hexafluoroisopropanol, polyetheramine 2000, N-methyldiethanolamine, glacial acetic acid, organotin catalyst, and acetone; the lower layer is prepared by a solution reaction of raw materials including the following components: isophorone diisocyanate, polyetheramine 2000, N-methyldiethanolamine, glacial acetic acid, liquid metal, gallic acid, and acetone. This dressing can achieve synergistic effects of protection, antibacterial properties, and electrical stimulation without the need for an external power source, and can be used as a wound healing accelerating dressing that mediates scarless repair, as well as other scar prevention medical materials.

Description

Technical Field

[0001] This invention belongs to the field of functional composite materials, specifically relating to a wound healing dressing, its preparation method, and its application. Background Technology

[0002] As the largest organ in the human body, the skin plays a vital role in maintaining fluid balance, resisting external pathogens, and regulating body temperature. When the skin is injured, the healing process typically involves multiple stages, including hemostasis, inflammation, proliferation, and remodeling. This process is influenced by a combination of factors, including cytokine regulation, cell migration and proliferation, angiogenesis, and extracellular matrix reconstruction. Ideally, wounds can heal completely through their own repair mechanisms. However, in real clinical settings, wounds often face challenges such as bacterial infection, chronic inflammation, and imbalances in the local microenvironment. These factors significantly delay the healing process, leading to chronic, difficult-to-heal wounds that severely impact quality of life, particularly among the elderly and patients with chronic diseases. Therefore, research on promoting wound healing is a crucial direction in the fields of biomaterials and regenerative medicine.

[0003] Traditional dressings primarily provide passive protection, mainly offering a physical barrier function, but lack the ability to actively regulate infection control and the healing process, making them unsuitable for treating complex wounds in dynamic environments. Furthermore, traditional dressings are significantly inadequate in terms of antibacterial properties and bioactivity regulation, often requiring additional antibiotics or frequent dressing changes, increasing treatment costs and potentially leading to drug resistance and secondary injury. Therefore, developing multifunctional dressings that combine dynamic protection, continuous antibacterial activity, and healing promotion is crucial for meeting complex clinical needs. Currently, wound dressings achieve multifunctional antibacterial and healing-promoting effects through the construction of composite systems (such as hydrogels, nanofibers, and composite coatings). Among these, combined electrical stimulation therapy provides a healthy and effective technical pathway to meet complex clinical needs. Electrical stimulation can regulate and activate the body's endogenous electrical signals, guiding tissue self-repair through physical stimulation and accelerating the wound healing process.

[0004] However, current combined electrostimulation therapy and antibacterial systems struggle to guarantee long-term dynamic adhesion of dressings, including good skin-to-dress fit and the stability of interfacial adhesion between multiple layers within the dressing. This reduces the sustainability of electrostimulation therapy and significantly limits its effectiveness in complex daily stress environments. A paper published in Appl. Mater. Today 2024, 37, 102120, using poly(L-lactic acid), polyethylene glycol, and tetragonal barium titanate nanoparticles as raw materials, prepared nanofiber membranes via electrospinning. This dressing could generate its own electricity through skin deformation and induce the production of reactive oxygen species, thus exerting an antibacterial effect. However, this study failed to achieve good skin adhesion, requiring an additional polyurethane membrane to adhere it to the skin surface, affecting the stability of long-term treatment. Chem. Eng. J. 2024, 491, 151801 prepared a... A dual-network piezoelectric nanofiber wound dressing with PVDF utilizes PVDF to achieve skin piezoelectric therapy. Achieving antibacterial properties, this dressing effectively promotes wound healing. However, this wound dressing lacks skin adhesion and requires a 3M Tegaderm membrane to fix it to the wound site, which cannot meet the needs of complex daily use scenarios. The paper Chem. Eng. J. 2024, 494, 153063 prepared a bilayer wound dressing by combining polyvinylidene fluoride film and silver micro / nano hydrogel particles. This dressing exhibits good antibacterial and electrotherapy effects, helping to promote wound healing. However, there is no effective interfacial interaction between the two layers, making it prone to interfacial slippage or delamination, which is not conducive to long-term use and affects the therapeutic effect. Currently, there are no reports of antibacterial self-generating wound dressings that possess dynamic adhesion properties at both the skin-dressing interface and the dressing's internal interface. Therefore, there is an urgent need to develop a wound-healing medical material that combines excellent dynamic adhesion stability, antibacterial properties, biocompatibility, and self-generating properties. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides an accelerated wound healing dressing, its preparation method, and its application. The composite material obtained by this invention can generate electricity through daily low-frequency sound waves and possesses tissue adhesion, biocompatibility, and skin flexibility. It can promote rapid wound repair and promote scarless wound healing by activating organs such as hair follicles.

[0006] The technical solution of the present invention:

[0007] A wound healing accelerating dressing, the wound healing accelerating dressing is composed of a double-layer structure; the upper layer is an antibacterial adhesive film; the lower layer is an antibacterial conductive film.

[0008] Furthermore, the amount of each substance added is calculated as 100 parts by weight for the upper layer and 300-700 parts by weight for the lower layer.

[0009] Furthermore, in the wound healing accelerated dressing, the upper layer structure has good biocompatibility, tissue adhesion, antibacterial properties and high electronegativity, while the lower layer structure has good biocompatibility, tissue adhesion, antibacterial properties and conductivity.

[0010] Furthermore, the upper structure is prepared by solution reaction of raw materials comprising the following components: 100 parts by weight of isophorone diisocyanate, 100-500 parts by weight of triphenylmethane triisocyanate, 10-50 parts by weight of hexafluoroisopropanol, 250-600 parts by weight of polyetheramine 2000, 30-50 parts by weight of N-methyldiethanolamine, 15-25 parts by weight of glacial acetic acid, 1-3 parts by weight of organotin catalyst, and 1500-6000 parts by weight of acetone.

[0011] Furthermore, the lower structure is prepared by solution reaction of raw materials comprising the following components: 100 parts by weight of isophorone diisocyanate, 100-550 parts by weight of polyetheramine 2000, 15-45 parts by weight of N-methyldiethanolamine, 5-22 parts by weight of glacial acetic acid, 1000-7000 parts by weight of liquid metal, 10-60 parts by weight of gallic acid, and 800-2500 parts by weight of acetone.

[0012] Furthermore, the organotin catalyst is one of dibutyltin disilicate, dioctyltin diacetate, or dioctyltin dilaurate; the liquid metal is one of gallium indium tin alloys with a melting point of -19°C to 20°C.

[0013] Furthermore, the preparation process of the upper structure is as follows: triphenylmethane triisocyanate, hexafluoroisopropanol and organotin catalyst are dissolved in acetone in proportion and reacted with stirring at room temperature; isophorone diisocyanate and polyetheramine 2000 are added in proportion and reacted with stirring; N-methyldiethanolamine is added in proportion and reacted with stirring; glacial acetic acid is added and reacted with stirring; finally, it is poured into a mold or coated into a film, and after drying, an antibacterial adhesive film is obtained.

[0014] Further, the preparation process of the lower structure is as follows: liquid metal is dispersed in an acetone solution containing gallic acid by ultrasonic pulverization to obtain a liquid metal-gallic acid dispersion for later use; isophorone diisocyanate, polyetheramine 2000 and N-methyldiethanolamine are dissolved in acetone in proportion and reacted by stirring at room temperature; glacial acetic acid is added and reacted by stirring; the prepared liquid metal-gallic acid dispersion is added in proportion and reacted by ultrasonication; the dispersion is poured or coated and dried to obtain an antibacterial conductive film.

[0015] Furthermore, in the preparation process of the upper structure: the first and third stirring reactions take 2-3 hours, the second stirring reaction takes 3-4 hours, and the fourth stirring reaction takes 1-2 hours.

[0016] Furthermore, in the preparation process of the lower structure: the ultrasonic pulverization time is 20-40 min, the first stirring reaction time is 2-4 h, the second stirring reaction time is 1-2 h, and the ultrasonic reaction time is 2-5 min.

[0017] A method for preparing a wound healing dressing includes the following steps: uniformly spraying a small amount of ethanol onto a lower antibacterial conductive film, then adhering an upper antibacterial adhesive film well to the lower layer, and drying at room temperature to achieve tight adhesion between the upper and lower layers.

[0018] An application of an accelerated wound healing dressing is disclosed. This dressing exhibits good biocompatibility and stretchability, allowing it to adhere tightly to the skin surface and flexibly conform to skin joints, protecting the fragile skin at the wound site. It also possesses good antibacterial properties, effectively inhibiting bacteria around the wound and reducing the incidence of wound infection. During daily skin bending, stretching, or pressure, it generates stable self-generated signals, forming a local micro-electric field that provides continuous electrical stimulation to the wound area. This promotes collagen and hair follicle regeneration, reduces wound inflammation, and helps accelerate wound healing while minimizing scar formation. Combining these properties, the dressing achieves a synergistic effect of protection, antibacterial properties, and electrical stimulation without the need for an external power source. It can be used as an accelerated wound healing dressing to mediate scarless repair and as other scar prevention medical materials.

[0019] The present invention has the following beneficial effects:

[0020] (1) The wound dressing structure of the present invention is a multi-layer encapsulation structure. The upper antibacterial adhesive film has strong stretchability and skin adhesion, ensuring that the dressing does not fall off under complex usage conditions. The lower antibacterial conductive film can provide good conductivity and tissue adhesion, and its adhesion is lower than that of the upper layer, avoiding secondary damage to the wound skin when changing the dressing. The double-layer material can form a cross-interface hydrogen bond network through ethanol to achieve strong interfacial adhesion between the two films, which helps to improve the stability of the dressing's self-generated electricity.

[0021] (2) The wound dressing of the present invention has excellent antibacterial properties. Its upper antibacterial adhesive film reduces bacterial adhesion by introducing fluorinated segments, while achieving contact sterilization by combining quaternary ammonium groups; the lower antibacterial conductive film utilizes the synergistic effect of the biologically derived antibacterial agent gallic acid and quaternary ammonium groups to exert an antibacterial effect. This design ensures the dressing's highly efficient antibacterial performance while effectively avoiding the problem of decreased biocompatibility that may result from excessive quaternary ammonium group content.

[0022] (3) The upper antibacterial adhesive film of the present invention improves the electronegativity of the film by introducing fluorine-containing segments. With the skin bending and deformation, the double-layer structure is easily compressed and deformed, so the interface charge between the high electronegativity fluorine-containing polyurethane upper layer and the low electronegativity metal composite lower layer is redistributed and accompanied by potential change, thereby realizing electrical stimulation at the wound site and promoting wound healing.

[0023] (4) The lower antibacterial conductive film of the present invention contains a polyphenolic structure of gallic acid that not only has antibacterial properties, but can also coat the liquid metal surface through coordination and promote the good dispersion of conductive filler in the substrate through multiple hydrogen bonding, which helps to achieve the conductivity uniformity of the lower antibacterial conductive film. The conductive filler gallium indium tin alloy is in a liquid state at room temperature, which not only has good biocompatibility and conductivity, but also has high deformation capacity. Even under high filling and large thickness conditions, its composite material can still maintain good skin compliance, which is conducive to achieving a continuous and stable electrical stimulation response during the dynamic deformation of the skin. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the adhesion of the antibacterial adhesive film, antibacterial conductive film, and wound healing accelerated dressing to the wrist skin in Example 1;

[0025] Figure 2 The images shown are scanning electron microscope images and corresponding X-ray energy dispersive spectroscopy images of the wound healing accelerated dressing in Example 1 (purple dots represent fluorine, red dots represent gallium, orange dots represent indium, and green dots represent tin).

[0026] Figure 3 This is a schematic diagram of the adhesion between the antibacterial adhesive film and the antibacterial conductive film in Example 1;

[0027] Figure 4 The self-generated power test of the wound healing dressing in Example 1 when the diameter of the lower antibacterial conductive film was changed under the triggering condition of an external force of 20N (where 0mm corresponds to power generation by the upper film alone).

[0028] Figure 5 These are photographs of Escherichia coli and Staphylococcus aureus grown on agar plates after being incubated with antibacterial adhesive film, antibacterial conductive film and wound healing accelerated dressing, respectively, in Example 1.

[0029] Figure 6 The image shows a fluorescence micrograph of fibroblasts co-cultured with the wound healing dressing filtrate in Example 1 after staining with Calcein-AM / PI live and dead cells (green indicates live cells, and red indicates dead cells).

[0030] Figure 7 The image shows H&E staining of the healed wound site in Example 1 after 9 days. Specific implementation methods

[0031] Unless otherwise specified, all reagents used in the embodiments of this invention can be purchased commercially.

[0032] It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the invention. In addition to the raw materials used in the embodiments of this invention, any raw material components that contain the same functional groups or include the same structural units involved in this invention, and which are replaced by equivalent substitutions, should be included within the scope of protection of this invention. The invention will be further described below with reference to specific embodiments.

[0033] The present invention provides accompanying drawings of detection results for some embodiments. Other embodiments and comparative examples use the same detection method. Those skilled in the art can directly and without doubt determine the content of the embodiments of the present invention using the detection method provided by the present invention.

[0034] The present invention will be further described below with reference to the embodiments.

[0035] Example 1

[0036] (1) Preparation of the upper structure antibacterial adhesive film: Weigh 250 parts by weight of triphenylmethane triisocyanate, 23 parts by weight of hexafluoroisopropanol, 2 parts by weight of dibutyltin dibutylsilicate and 2500 parts by weight of acetone into a three-necked flask and stir at room temperature for 3 hours; add 100 parts by weight of isophorone diisocyanate and 410 parts by weight of polyetheramine 2000 and stir at room temperature for 3 hours; add 41 parts by weight of N-methyldiethanolamine and stir at room temperature for 2 hours; add 20 parts by weight of glacial acetic acid and stir at room temperature for 1 hour; finally, pour into a mold to form a film, and dry to obtain the antibacterial adhesive film.

[0037] (2) Preparation of the lower layer antibacterial conductive film: 4000 parts by weight of 6℃ gallium indium tin alloy were dispersed in an acetone dispersion containing gallic acid (500 parts acetone and 40 parts gallic acid) by ultrasonic pulverization, and ultrasonicated for 35 min for later use; 100 parts by weight of isophorone diisocyanate, 310 parts of polyetheramine 2000, 30 parts of N-methyldiethanolamine and 1300 parts of acetone were placed in a three-necked flask and stirred at room temperature for 3 h; 15 parts of glacial acetic acid were added and stirred at room temperature for 1.5 h; the gallium indium tin alloy-gallic acid dispersion was added, ultrasonicated for 2 min, poured into a mold to form a film, and dried to obtain the antibacterial conductive film.

[0038] (3) Preparation of wound healing accelerated dressing: 100 parts by weight of square antibacterial adhesive film and 500 parts by weight of circular antibacterial conductive film were cut and weighed; a small amount of ethanol was evenly sprayed on the lower antibacterial conductive film, and then the upper antibacterial adhesive film was well adhered to it. After drying at room temperature, the upper and lower layers were tightly adhered to obtain the wound healing accelerated dressing. It was pasted on the wound surface, and the wound recovery status is shown in Table 1. After 9 days, skin tissue was taken for H&E staining to observe the hair follicle regeneration. The hair follicle activation status is shown in Table 2.

[0039] Example 2

[0040] (1) Preparation of the upper structure antibacterial adhesive film: Weigh 450 parts by weight of triphenylmethane triisocyanate, 42 parts by weight of hexafluoroisopropanol, 3 parts by weight of dioctyltin diacetate and 6000 parts by weight of acetone into a three-necked flask and stir at room temperature for 3 hours; add 100 parts by weight of isophorone diisocyanate and 490 parts by weight of polyetheramine 2000 and stir at room temperature for 4 hours; add 49 parts by weight of N-methyldiethanolamine and stir at room temperature for 3 hours; add 25 parts by weight of glacial acetic acid and stir at room temperature for 2 hours; finally, pour into a mold to form a film, and after drying, obtain the antibacterial adhesive film.

[0041] (2) Preparation of the lower layer antibacterial conductive film: 6500 parts by weight of 3℃ gallium indium tin alloy were dispersed in an acetone dispersion containing gallic acid (500 parts acetone and 60 parts gallic acid) by ultrasonic pulverization, and ultrasonicated for 40 min for later use; 100 parts by weight of isophorone diisocyanate, 530 parts of polyetheramine 2000, 18 parts of N-methyldiethanolamine and 2000 parts of acetone were placed in a three-necked flask and stirred at room temperature for 4 h; 8 parts of glacial acetic acid were added and stirred at room temperature for 1 h; the gallium indium tin alloy-gallic acid dispersion was added, ultrasonicated for 5 min, poured into a mold to form a film, and dried to obtain the antibacterial conductive film.

[0042] (3) Preparation of wound healing accelerated dressing: 100 parts by weight of square antibacterial adhesive film and 700 parts by weight of circular antibacterial conductive film were cut and weighed; a small amount of ethanol was evenly sprayed on the lower antibacterial conductive film, and then the upper antibacterial adhesive film was well adhered to it. After drying at room temperature, the upper and lower layers were tightly adhered to obtain the wound healing accelerated dressing. It was pasted on the wound surface, and the wound recovery status is shown in Table 1. After 9 days, skin tissue was taken for H&E staining to observe the hair follicle regeneration. The hair follicle activation status is shown in Table 2.

[0043] Example 3

[0044] (1) Preparation of the upper structure antibacterial adhesive film: Weigh 250 parts by weight of triphenylmethane triisocyanate, 23 parts by weight of hexafluoroisopropanol, 2 parts by weight of dioctyltin dilaurate and 1500 parts by weight of acetone into a three-necked flask and stir at room temperature for 3 hours; add 100 parts by weight of isophorone diisocyanate and 273 parts by weight of polyetheramine 2000 and stir at room temperature for 3 hours; add 49 parts by weight of N-methyldiethanolamine and stir at room temperature for 3 hours; add 25 parts by weight of glacial acetic acid and stir at room temperature for 2 hours; finally, pour into a mold to form a film, and after drying, obtain the antibacterial adhesive film.

[0045] (2) Preparation of the lower layer antibacterial conductive film: 2600 parts by weight of 11℃ gallium indium tin alloy were dispersed in an acetone dispersion containing gallic acid (500 parts acetone and 26 parts gallic acid) by ultrasonic pulverization, and ultrasonicated for 27 min for later use; 100 parts by weight of isophorone diisocyanate, 310 parts of polyetheramine 2000, 30 parts of N-methyldiethanolamine and 1300 parts of acetone were placed in a three-necked flask and stirred at room temperature for 3 h; 15 parts of glacial acetic acid were added and stirred at room temperature for 1.5 h; the gallium indium tin alloy-gallic acid dispersion was added, ultrasonicated for 2 min, poured into a mold to form a film, and dried to obtain the antibacterial conductive film.

[0046] (3) Preparation of wound healing accelerated dressing: 100 parts by weight of square antibacterial adhesive film and 400 parts by weight of circular antibacterial conductive film were cut and weighed; a small amount of ethanol was evenly sprayed on the lower antibacterial conductive film, and then the upper antibacterial adhesive film was well adhered to it. After drying at room temperature, the upper and lower layers were tightly adhered to obtain the wound healing accelerated dressing. It was pasted on the wound surface, and the wound recovery status is shown in Table 1. After 9 days, skin tissue was taken for H&E staining to observe the hair follicle regeneration status, and the hair follicle activation status is shown in Table 2.

[0047] Example 4

[0048] (1) Preparation of the upper structure antibacterial adhesive film: Weigh 250 parts by weight of triphenylmethane triisocyanate, 23 parts by weight of hexafluoroisopropanol, 2 parts by weight of dibutyltin dibutylsilicate and 3000 parts by weight of acetone into a three-necked flask and stir at room temperature for 3 hours; add 100 parts by weight of isophorone diisocyanate and 550 parts by weight of polyetheramine 2000 and stir at room temperature for 3 hours; add 30 parts by weight of N-methyldiethanolamine and stir at room temperature for 2 hours; add 16 parts by weight of glacial acetic acid and stir at room temperature for 1 hour; finally, coat the film and dry to obtain the antibacterial adhesive film.

[0049] (2) Preparation of the lower layer antibacterial conductive film: 4000 parts by weight of 16℃ gallium indium tin alloy were dispersed in an acetone dispersion containing gallic acid (500 parts acetone and 40 parts gallic acid) by ultrasonic pulverization, and ultrasonicated for 35 min for later use; 100 parts by weight of isophorone diisocyanate, 310 parts of polyetheramine 2000, 30 parts of N-methyldiethanolamine and 1300 parts of acetone were placed in a three-necked flask and stirred at room temperature for 3 h; 15 parts of glacial acetic acid were added and stirred at room temperature for 1.5 h; the gallium indium tin alloy-gallic acid dispersion was added, ultrasonicated for 2 min, coated into a film, and dried to obtain the antibacterial conductive film.

[0050] (3) Preparation of wound healing accelerated dressing: 100 parts by weight of square antibacterial adhesive film and 500 parts by weight of circular antibacterial conductive film were cut and weighed; a small amount of ethanol was evenly sprayed on the lower antibacterial conductive film, and then the upper antibacterial adhesive film was well adhered to it. After drying at room temperature, the upper and lower layers were tightly adhered to obtain the wound healing accelerated dressing. It was pasted on the wound surface, and the wound recovery status is shown in Table 1. After 9 days, skin tissue was taken for H&E staining to observe the hair follicle regeneration. The hair follicle activation status is shown in Table 2.

[0051] Example 5

[0052] (1) Preparation of the upper structure antibacterial adhesive film: Weigh 107 parts by weight of triphenylmethane triisocyanate, 10 parts of hexafluoroisopropanol, 1 part of dibutyltin disilicate and 2000 parts of acetone into a three-necked flask and stir at room temperature for 2 hours; add 100 parts of isophorone diisocyanate and 350 parts of polyetheramine 2000 and stir at room temperature for 3 hours; add 35 parts of N-methyldiethanolamine and stir at room temperature for 2 hours; add 17 parts of glacial acetic acid and stir at room temperature for 1 hour; finally, coat the film and dry to obtain the antibacterial adhesive film.

[0053] (2) Preparation of the lower layer antibacterial conductive film: 1150 parts by weight of -19℃ gallium indium tin alloy were dispersed in an acetone dispersion containing gallic acid (500 parts acetone and 11 parts gallic acid) by ultrasonic pulverization, and ultrasonicated for 20 min for later use; 100 parts by weight of isophorone diisocyanate, 102 parts of polyetheramine 2000, 43 parts of N-methyldiethanolamine and 500 parts of acetone were placed in a three-necked flask and stirred at room temperature for 2 h; 22 parts of glacial acetic acid were added and stirred at room temperature for 2 h; the gallium indium tin alloy-gallic acid dispersion was added, ultrasonicated for 3 min, coated into a film, and dried to obtain the antibacterial conductive film.

[0054] (3) Preparation of wound healing accelerated dressing: 100 parts by weight of square antibacterial adhesive film and 300 parts by weight of circular antibacterial conductive film were cut and weighed; a small amount of ethanol was evenly sprayed on the lower antibacterial conductive film, and then the upper antibacterial adhesive film was well adhered to it. After drying at room temperature, the upper and lower layers were tightly adhered to obtain the wound healing accelerated dressing. It was pasted on the wound surface, and the wound recovery status is shown in Table 1. After 9 days, skin tissue was taken for H&E staining to observe the hair follicle regeneration. The hair follicle activation status is shown in Table 2.

[0055] Comparative Example 1

[0056] The antibacterial adhesive film of Example 1 was directly applied to the wounds of mice, and the wound healing status is shown in Table 1. After 9 days, skin tissue was taken for H&E staining to observe hair follicle regeneration, and the activation status is shown in Table 2.

[0057] Comparative Example 2

[0058] The antibacterial conductive film of Example 1 was directly applied to the wounds of mice, and the wound healing status is shown in Table 1. After 9 days, skin tissue was taken for H&E staining to observe hair follicle regeneration, and the activation status is shown in Table 2.

[0059] Comparative Example 3

[0060] Keeping all other aspects of Example 1 (1) and (2) unchanged, in (3) the preparation of the wound healing dressing was prepared by unevenly spraying ethanol to firmly adhere the upper and lower layers, and only by pressing the upper and lower layers together by hand to adhere them together, thus preparing the wound dressing. Finally, the wound dressing was applied to the wound of the mouse, and the wound recovery status is shown in Table 1. After 9 days, skin tissue was taken for H&E staining to observe the hair follicle regeneration, and the activation status is shown in Table 2.

[0061] Table 1 Wound healing rate

[0062]

[0063] Table 2 Hair follicle regeneration status (9 days)

[0064]

[0065] Comparing Tables 1 and 2, since the wound dressings in Comparative Examples 1 and 2 could not generate electricity, they could not provide electrical stimulation to the wound, resulting in slower wound healing and the inability to generate new hair follicles. This demonstrates that the self-generating power of the self-healing wound dressing promotes wound repair and hair follicle activation, which helps mediate scarless repair. In Comparative Example 3, the wound dressing could not achieve hydrogen bond rearrangement due to the lack of solvent-assisted interface reconstruction between the upper and lower layers. The poor stability of the bilayer structure led to unstable electrical stimulation treatment in the later stages of wound healing, resulting in slower wound healing and the inability to generate new hair follicles. This demonstrates the important role of the stability of the interfacial adhesion between the multiple layers of materials in the dressing for self-generating treatment.

[0066] Figure 1 Antibacterial adhesive films, antibacterial conductive films, and wound-healing dressings all adhere well to the skin of the wrist and do not fall off when the skin is bent, indicating that they have good tissue adhesion and skin compliance, which is beneficial for effective treatment in the complex daily treatment environment.

[0067] Figure 2 The energy dispersive spectroscopy (EDS) image shows a uniform fluorine signal in the upper antibacterial adhesive film, proving that the successful introduction of fluorine-containing segments helps to improve the electronegativity of the upper film. In the lower antibacterial conductive film, gallium, indium, and tin elements do not aggregate over a large area, proving that the liquid metal is uniformly dispersed, which is conducive to the rapid and uniform transmission of electrical signals and improves the stability of electrical stimulation therapy.

[0068] Figure 3 Ethanol is used as an interface modulator between the antibacterial adhesive film and the antibacterial conductive film to disrupt the original hydrogen bonds between the monolayer polymer chains, thereby achieving cross-interface hydrogen bond network reconstruction and strong interfacial adhesion between the two films, which helps to improve the long-term stability of the dressing's electrical stimulation.

[0069] Figure 4 When only the upper layer was tested for piezoelectricity, its output voltage was significantly lower than that of the double-layer structure sample, indicating that electron transfer between the double layers played a key role in energy conversion. Meanwhile, the generation of piezoelectricity in other groups of wound healing dressings proved that wound healing dressings can convert mechanical force into electrical signals to achieve electrical stimulation therapy at the wound site.

[0070] Figure 5 When co-incubated with antibacterial adhesive film, antibacterial conductive film and wound healing dressing, Escherichia coli and Staphylococcus aureus could not reproduce normally, achieving a good multi-layer antibacterial effect;

[0071] Figure 6 The fluorescence micrographs after staining live and dead cells did not show a large number of dead cells, and the live cells exhibited a healthy fibrous structure and good proliferation state, proving that the wound healing dressing has good biocompatibility.

[0072] Figure 7 H&E staining of the healing wound site revealed newly formed, intact skin structures, especially clearly visible new hair follicles, demonstrating that wound-healing dressings can activate wound hair follicles and mediate scarless wound healing.

Claims

1. A wound healing accelerating dressing, characterized in that: The wound healing accelerating dressing consists of a double-layer structure; the upper layer is an antibacterial adhesive film; and the lower layer is an antibacterial conductive film.

2. The wound healing accelerating dressing according to claim 1, characterized in that: The amount of each substance added is calculated based on 100 parts by weight for the upper layer and 300-700 parts by weight for the lower layer.

3. The wound healing accelerating dressing according to claim 1, characterized in that, In the aforementioned wound healing accelerated dressing, the upper layer structure has good biocompatibility, tissue adhesion, antibacterial properties and high electronegativity, while the lower layer structure has good biocompatibility, tissue adhesion, antibacterial properties and electrical conductivity.

4. The wound healing accelerating dressing according to claim 1, characterized in that, The upper structure is prepared by solution reaction of raw materials comprising the following components: 100 parts by weight of isophorone diisocyanate, 100-500 parts by weight of triphenylmethane triisocyanate, 10-50 parts by weight of hexafluoroisopropanol, 250-600 parts by weight of polyetheramine 2000, 30-50 parts by weight of N-methyldiethanolamine, 15-25 parts by weight of glacial acetic acid, 1-3 parts by weight of organotin catalyst, and 150 parts by weight of acetone. 0-6000 parts by weight; the lower structure is prepared by solution reaction of raw materials comprising the following components: 100 parts by weight of isophorone diisocyanate, 100-550 parts by weight of polyetheramine 2000, 15-45 parts by weight of N-methyldiethanolamine, 5-22 parts by weight of glacial acetic acid, 1000-7000 parts by weight of liquid metal, 10-60 parts by weight of gallic acid, and 800-2500 parts by weight of acetone.

5. The wound healing accelerating dressing according to claim 4, characterized in that, The organotin catalyst is one of dibutyltin disilicate, dioctyltin diacetate, or dioctyltin dilaurate; the liquid metal is one of gallium indium tin alloys with a melting point of -19°C to 20°C.

6. The wound healing accelerating dressing according to claim 4, characterized in that, The preparation process of the upper structure is as follows: triphenylmethane triisocyanate, hexafluoroisopropanol, and organotin catalyst are dissolved in acetone in proportion and reacted with stirring at room temperature; isophorone diisocyanate and polyetheramine 2000 are added in proportion and reacted with stirring; N-methyldiethanolamine is added in proportion and reacted with stirring; glacial acetic acid is added and reacted with stirring; finally, it is poured into a mold or coated onto a film and dried to obtain an antibacterial adhesive film. The preparation process of the lower structure is as follows: liquid metal is dispersed in an acetone solution containing gallic acid by ultrasonic pulverization to obtain a liquid metal-gallic acid dispersion for later use; isophorone diisocyanate, polyetheramine 2000, and N-methyldiethanolamine are dissolved in acetone in proportion and reacted with stirring at room temperature; glacial acetic acid is added and reacted with stirring; the prepared liquid metal-gallic acid dispersion is added in proportion and reacted with ultrasonication; the dispersion is poured or coated onto a film and dried to obtain an antibacterial conductive film.

7. The wound healing accelerating dressing according to claim 6, characterized in that, In the preparation of the upper structure: the first and third stirring reactions take 2-3 hours, the second stirring reaction takes 3-4 hours, and the fourth stirring reaction takes 1-2 hours.

8. The wound healing accelerating dressing according to claim 6, characterized in that, In the preparation of the lower structure: the ultrasonic pulverization time is 20-40 min, the first stirring reaction time is 2-4 h, the second stirring reaction time is 1-2 h, and the ultrasonic reaction time is 2-5 min.

9. A method for preparing a wound-healing dressing according to any one of claims 1-8, characterized in that, Includes the following steps: A small amount of ethanol is evenly sprayed onto the lower antibacterial conductive film, and then the upper antibacterial adhesive film is well bonded to the lower layer. After drying at room temperature, the upper and lower layers are tightly bonded.

10. The application of the wound-healing dressing according to any one of claims 1-8 or the wound-healing dressing obtained by the preparation method of claim 9, characterized in that, The wound healing acceleration dressing is used in wound healing acceleration dressings that mediate scarless repair and other scar prevention medical materials.

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