Programmable hydrogel wound dressing with rotary contraction force and application thereof

Abstract

The invention provides a programmable hydrogel wound dressing with rotation contraction force and application thereof, and belongs to the technical field of biomedical materials, the programmable hydrogel wound dressing comprises a dual-network hydrogel main body, a first hydrogel layer, a second hydrogel layer, a first hydrogel layer and a second hydrogel layer, and the dual-network hydrogel main body is composed of a first network and a second network; the first network is a chemically cross-linked methacrylated hyaluronic acid network and forms a cross-linked network structure through photopolymerization; the second network is a physical cross-linked polyvinyl alcohol network, and forms an instantaneous cross-linking point with a crystal region through a hydrogen bond, so that the hydrogel is endowed with shape memory performance; the surface is modified with an N-hydroxysuccinimide ester functional group, and the N-hydroxysuccinimide ester functional group and amino of wound tissue protein can form a covalent bond; the dual-network hydrogel main body is subjected to pre-stretching or pre-twisting treatment and then is dried and shaped into a preset shape, the initial shape is recovered after moisture is absorbed, and rotary contraction mechanical force is output. Rapid wound healing and scar-free regeneration are achieved by dynamically regulating and controlling wound edge mechanical force and enhancing tissue adhesion, and then application to regulation and control of wound microenvironment to promote scar-free healing is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of biomedical materials, in particular to a programmable hydrogel wound dressing with rotary contractile force and application thereof. BACKGROUND

[0002] Mechanical tension is a key factor in regulating fibroblast behavior, collagen deposition and scar formation - moderate tension can promote cell migration and angiogenesis, while high intensity and persistent stress can lead to sustained activity of myofibroblasts, inducing abnormal scars.

[0003] Currently, the tension reduction means used in clinical practice (such as silicone sheets, compression garments, tension suture devices, etc.) have significant limitations: first, they lack dynamic control capability and can only provide static or passive tension reduction, which cannot meet the needs of different healing stages of the wound surface; second, the force field direction is single, mostly linear or vertical force, ignoring the complex multidirectional stress distribution of the wound margin, which is easy to cause stress concentration; third, the wet environment adaptability is poor, most materials are easy to slip off in a wet wound surface, and it is difficult to have a lasting effect; fourth, the shape memory function and mechanical regulation strategy have not been integrated, and the spatial programmable output of force cannot be achieved. In addition, although some studies have shown that intervention in mechanical signaling pathways such as YAP or TGF-β can reduce scars, these pathways are essential for cell proliferation and matrix synthesis in the early stages of healing, and single inhibition cannot balance tissue regeneration and scar inhibition. Therefore, there is an urgent need for a hydrogel wound dressing with programmable mechanical output capability, good tissue adhesion performance, and the ability to dynamically adjust the mechanical microenvironment of the wound margin, in order to achieve scar-free tissue regeneration and repair. SUMMARY

[0004] In order to overcome the shortcomings of the prior art, the purpose of the present application is to provide a programmable hydrogel wound dressing with rotary contractile force and application thereof.

[0005] To achieve the above-mentioned purpose, the present application provides the following solutions: One of the purposes of the present application is to provide a programmable hydrogel wound dressing with rotary contractile force, comprising: A double-network hydrogel body, which is composed of a first network and a second network; the first network is a chemically cross-linked methacrylated hyaluronic acid network, which forms an interpenetrating network structure through photopolymerization; the second network is a physically cross-linked polyvinyl alcohol network, which forms transient cross-linking points with crystal regions through hydrogen bonds, giving the hydrogel shape memory properties; The surface of the double-network hydrogel body is modified with N-hydroxysuccinimide ester functional groups, which can form covalent bonds with the amino groups of the proteins in the wound tissue; The double-network hydrogel body is dried and shaped into a preset shape after pre-stretching or pre-twisting treatment, and restores the original shape and outputs a rotary contractile mechanical force after absorbing moisture.

[0006] The second object of the present application is to provide a preparation method of the programmable hydrogel wound dressing with rotational contractile force, comprising the following steps: S1, mixing polyvinyl alcohol solution and methacrylated hyaluronic acid solution, adding photoinitiator and acrylic acid-NHS, and completing photopolymerization by ultraviolet irradiation to obtain a wet state double network hydrogel; S2, after the wet state double network hydrogel is treated by pre-stretching or pre-twisting, drying at 50-60℃ for 40-50 hours to form a shape memory structure, thereby obtaining the programmable hydrogel wound dressing.

[0007] The third object of the present application is to provide a use method of the programmable hydrogel wound dressing with rotational contractile force, which is attached to the surface of a moist wound, and after the programmable hydrogel wound dressing absorbs wound exudate, it starts shape recovery and outputs directional mechanical stimulation to the wound margin.

[0008] The fourth object of the present application is to provide an application of the programmable hydrogel wound dressing with rotational contractile force in regulating the microenvironment of a wound to promote scarless healing.

[0009] According to the specific embodiments provided by the present application, the following technical effects are disclosed: (1) The programmable hydrogel wound dressing provided by the present application has the ability to precisely regulate the mechanical microenvironment of the wound margin, and through the design of the shape memory structure, it can output tension or rotational stress with controllable direction and adjustable strength at different stages of the wound, realizing the spatiotemporal redistribution of local stress on the wound margin. Animal experiments show that it can promote the activation of YAP and TGF-β signaling pathways in the early stage to accelerate cell migration and angiogenesis, and inhibit related pathways in the late stage to reduce excessive collagen deposition, thereby balancing tissue regeneration and scar inhibition.

[0010] (2) The programmable hydrogel wound dressing provided by the present application can significantly improve wound closure efficiency and tissue reconstruction quality, while reducing scar formation. In a diabetic mouse model, the wound closure rate of the treatment group using the medium rotational force patch was more than 80% on the 16th day, which was much higher than that of the control group; in a rabbit ear scar model, the scar area was significantly smaller than that of the control group after 8 weeks of treatment, and the collagen fibers were arranged more closely to normal skin, with both aesthetic and functional properties.

[0011] (3) The programmable hydrogel wound dressing provided by the present application also has excellent practical performance, and the surface NHS group modification enables it to have high adhesion strength on a moist tissue surface, with a tensile adhesion strength of 120kPa and an interfacial fracture toughness of more than 450J / m 2, can stably act on complex wound surface. The mechanical output response is fast, and the effective shape recovery and force output can be completed within 20 seconds without external energy, which is convenient for clinical operation. Meanwhile, the material is biodegradable, low-cost and easy to mass-produce, reducing the need for subsequent treatments such as postoperative scar repair, skin grafting or laser therapy, thereby reducing medical costs, and is especially suitable for various clinical scenarios such as diabetic foot, burns and plastic surgery. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 SEM image of the programmable hydrogel wound dressing with rotary contraction force; Figure 2 Shape memory mechanism diagram of the programmable hydrogel wound dressing with rotary contraction force; Figure 3 Pre-set shape and mechanical output mode diagram of the programmable hydrogel wound dressing with rotary contraction force; wherein, Figure 3 (a) in the above is a schematic diagram of the pre-set shape and the corresponding mechanical output mode, Figure 3 (b) in the above is a schematic diagram of stress concentration distribution on the wound edge without the patch, Figure 3 (c) in the above is a schematic diagram of stress dispersion distribution on the wound edge after activation of the rotary contraction patch, Figure 3 (d) in the above is a comparison diagram of wound area changes at 0 minutes and 20 minutes in different treatment groups of a pig skin round wound model; Figure 4 Preparation method flow chart of the programmable hydrogel wound dressing with rotary contraction force; Figure 5 Use state and mechanism diagram of the programmable hydrogel wound dressing with rotary contraction force; wherein, Figure 5 (a) in the above is a schematic diagram of the three stages of wound healing (inflammation stage, proliferation stage and remodeling stage) and the dynamic change characteristics of the tissue, Figure 5 (b) in the above is a schematic diagram of the mechanism of preventing scar formation by programmable external stress, Figure 5 (c) in the above is a schematic diagram of the application model of the hydrogel patch attached to the skin wound; Figure 6 Performance data diagram of the programmable hydrogel wound dressing with rotary contraction force; wherein, Figure 6 (a) in the above is an infrared spectrum diagram of unmodified and modified NHS ester hydrogel, Figure 6 (b) in the above is a water absorption and swelling curve diagram of unmodified and modified NHS ester hydrogel, Figure 6 (c) in the above is a comparison diagram of storage modulus (G') and loss modulus (G'') of unmodified and modified NHS ester hydrogel at different frequencies, Figure 6(d) in the figure represents the tensile stress-strain curves of unmodified and modified NHS ester hydrogels. Figure 6 (e) shows a schematic diagram of the overlap shear experiment and shear stress-displacement curves of unmodified and modified NHS ester hydrogels. Figure 6 (f) shows a schematic diagram of the 180° shear experiment and shear force-displacement curves of unmodified and modified NHS ester hydrogels. Figure 6 (g) in the figure is a schematic diagram of the tensile test and tensile stress-displacement curves of unmodified and modified NHS ester hydrogels. Figure 6 (h) in the figure is a comparison of the interfacial shear force and tensile force test results of unmodified and modified NHS ester hydrogels. Figure 6 (i) in the figure shows the test results of the overlap shear stress of the hydrogel on different tissues. Figure 6 Figure (j) shows the test results of the adhesion force of the hydrogel to the 180° shear interface of different tissues. Figure 6 (k) in the figure is a comparison of the wound-closing force of the modified NHS ester hydrogel and the commercial material; Figure 7 This is a performance graph evaluating the wound healing effect of the present invention in a diabetic mouse model; wherein, Figure 7 (a) shows the wound appearance photographs on days 0, 4, 8, and 16 in a 5mm full-thickness skin defect model on the back of diabetic mice in different treatment groups. Figure 7 (b) in the figure shows the quantitative curves of wound area changes over time for different treatment groups. Figure 7 (c) shows the H&E staining images of wound tissues from different treatment groups on days 8 and 16. Figure 7 (d) in the figure is a quantitative analysis of the degree of wound reepithelialization in different treatment groups; Figure 8 This is a schematic diagram illustrating the wound healing mechanism controlled by the rotational shrinkage hydrogel patch according to the present invention; wherein, Figure 8 (a) in the figure shows the quantitative analysis of IL-6 expression levels in different treatment groups. Figure 8 (b) in the figure shows the quantitative analysis of TNF-α expression levels in different treatment groups. Figure 8 (c) in the figure is a quantitative analysis diagram of CD31 positive blood vessel density in different treatment groups; Figure 9 This is a schematic diagram illustrating the wound healing mechanism controlled by the rotational shrinkage hydrogel patch according to the present invention; wherein, Figure 9 (a) in the figure is a quantitative analysis of α-SMA expression levels in different treatment groups. Figure 9 (b) in the figure shows the quantitative analysis of TGF-β expression levels in different treatment groups. Figure 8 (c) in the figure is a quantitative analysis diagram of YAP expression levels in different treatment groups; Figure 10This is a long-term evaluation diagram of scar remodeling and tissue regeneration in a rabbit ear hypertrophic scar model according to the present invention; wherein, Figure 10 Image (a) shows the wound appearance of different treatment groups at weeks 0, 2, 4, 6, and 8 in the rabbit ear hypertrophic scar model. Figure 10 Image (b) shows the H&E staining images of wound tissues from different treatment groups at weeks 4 and 8. Figure 10 (c) shows the Masson trichrome staining images of wound tissues from different treatment groups at weeks 4 and 8; Figure 11 This is a long-term evaluation diagram of scar remodeling and tissue regeneration in a rabbit ear hypertrophic scar model according to the present invention; wherein, Figure 11 Image (a) shows SiriusRed staining images of wound tissues from different treatment groups at weeks 4 and 8 under polarized light. Figure 11 (b) in the figure is a quantitative analysis graph of the CD31 signal intensity of different treatment groups. Figure 11 (c) in the figure is a quantitative analysis diagram of the α-SMA signal intensity of different treatment groups; Figure 12 This is a schematic diagram illustrating the molecular mechanism by which the hydrogel patch promotes healing and reduces scarring through transcriptome analysis, as revealed by the present invention; wherein, Figure 12 (a) shows a circular heatmap of whole-genome expression in wound tissues from different treatment groups at week 4. Figure 12 (b) in the figure shows the differential gene volcano diagram between the Rt-MC group and the RaC group; Figure 13 GO enrichment analysis diagram for differentially expressed genes; Figure 14 KEGG pathway analysis diagram of differentially expressed genes; Figure 15 This is a schematic diagram illustrating the molecular mechanism by which the hydrogel patch promotes healing and reduces scarring through transcriptome analysis, as revealed by the present invention; wherein, Figure 15 Image (a) shows immunofluorescence images of TGF-β and YAP in wound tissues from different treatment groups at weeks 4 and 8. Figure 15 (b) in the figure is a quantitative analysis of the relative expression levels of TGF-β protein in different treatment groups. Figure 15 (c) in the figure is a quantitative analysis of the relative expression levels of YAP protein in different treatment groups; Among them, in the bar chart corresponding to the above-mentioned attached figures, " "" is a marker for statistically significant differences, specifically defined as follows: Different numbers of " Different "P-values" (probability values) indicate whether the difference between two groups of data (such as the experimental group and the control group, or different experimental groups) is statistically significant. “ ": This means P < 0.05, which means the difference between the two groups is "statistically significant" (probability of occurrence < 5%). “ ": This means P < 0.01, which means the difference between the two groups is "highly statistically significant" (probability of occurrence < 1%). “ “”: This means P < 0.001, which means the difference between the two groups is “highly statistically significant” (probability of occurrence < 0.1%). “ ": represents P<0.0001, meaning the difference between the two groups is "highly statistically significant" (probability of occurrence <0.01%).

[0013] Referring to the example, in Figure 1 middle" Its specific function is: This is used to assess the statistical reliability of differences in TGF-β and YAP protein expression levels between the Rt-MC (medium-tension rotational shrinkage patch) group, RaC (simple radial shrinkage patch) group, Rt-HC (high-tension rotational shrinkage patch) group, and TEG (commercial dressing control group), or between different experimental groups. For example, it is used to assess the statistical reliability of differences in TGF-β and YAP protein expression levels between the Rt-MC group and the TEG group. "This indicates that the difference in protein expression levels between the two is extremely significant, the results are reliable, and the influence of random factors has been excluded." Detailed Implementation

[0014] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Figure 2 As shown, the present invention provides a programmable hydrogel wound dressing with rotational contraction force, comprising: The dual-network hydrogel matrix consists of a first network and a second network. The first network is a chemically cross-linked methacryloyl hyaluronic acid (HAMA) network, which forms a cross-linked network structure through photopolymerization. Specifically, the concentration of methacryloyl hyaluronic acid is 3-5 vol%, and photopolymerization occurs when 0.05-0.2 wt% of photoinitiator LAP is added and irradiated with 365 nm ultraviolet light for 10-20 seconds to form a stable three-dimensional cross-linked network structure. The second network is a physically cross-linked polyvinyl alcohol (PVA) network with a polyvinyl alcohol concentration of 8-12 wt%. It forms reversible, transient cross-linking points with the crystalline regions through hydrogen bonds, endowing the hydrogel with shape memory properties. Its reversible destruction and reconstruction of the crystalline regions is the main principle behind shape recovery. Figure 6As shown, the hydrogel exhibits hydration in three states: initial, stretched and dried, and hydrated. It's important to note that hydration refers to the process by which the hydrogel absorbs moisture and returns to a moist state, consistent with the concept of "rehydration." In the initial state, the polyvinyl alcohol (PVA) chains in the hydrogel form numerous hydrogen bonds and crystalline regions (i.e., transient cross-linking points TCPs), working synergistically with the chemical cross-linking network formed by methacryloyl hyaluronic acid (HAMA). At this point, the hydrogel is fully hydrated, and the hydrogen bonds and crystalline region structure of the PVA segments are stable. When the hydrogel is pre-stretched and dried, moisture loss disrupts the crystalline regions (TCPs) of the PVA segments, causing hydrogen bonds to break, stress to lock, and forming a pre-defined dehydrated shape. When the dried hydrogel patch absorbs moisture (such as wound exudate) and undergoes hydration (i.e., rehydration), the PVA segments reform hydrogen bonds and rebuild crystalline regions (TCPs), releasing stored elastic energy and driving the hydrogel back to its initial fully hydrated state. Simultaneously, it outputs rotational contraction mechanical force, achieving shape memory-driven behavior.

[0015] In addition, the surface of the dual-network hydrogel is modified with N-hydroxysuccinimide ester functional groups. Specifically, by introducing 1-3 wt% acrylic acid-NHS (AAc-NHS) comonomer during the hydrogel preparation process, the surface of the hydrogel is modified with N-hydroxysuccinimide (NHS) ester functional groups, which can rapidly form covalent bonds with the amino groups of wound tissue proteins, ensuring high-strength adhesion in a moist environment. Figure 3 As shown in (a), the infrared spectrum confirms the presence of characteristic absorption peaks of the NHS ester group by comparing relevant characteristic peaks, thus proving that the acrylic acid-NHS (AAc-NHS) comonomer successfully participated in the reaction during the preparation of the hydrogel, modifying the hydrogel surface with NHS ester functional groups. The presence of this functional group is the key basis for the hydrogel to form stable covalent bonds with the amino groups of wound tissue proteins, thereby achieving high-strength tissue adhesion performance in a moist environment, and providing an important guarantee for the stable effect of the hydrogel on the wound.

[0016] The dual-network hydrogel matrix, after pre-stretching or pre-twisting treatment, is dried and shaped into a preset form. Upon absorbing moisture, it returns to its initial shape and outputs mechanical force. The preset shape includes one or more of spiral, radial, and strip-like forms, and the corresponding output mechanical force modes include one or more of radial contraction, rotational contraction, and tension release. Figure 3As shown in (a), the spiral, radial, and strip patterns correspond to three mechanical modes: rotational contraction, radial contraction, and tension release, respectively. The spiral patch, with its pre-twist angle (Δα = 35°~45°), generates rotational torque after rehydration; the radial patch drives centripetal contraction through a high pre-stretch ratio (Δλ = 40%); and the strip patch releases uniform longitudinal tension. This programmable design solves the problem of the single mechanical direction of traditional dressings, and can directly match the biomechanical needs of linear, circular, or irregular wounds.

[0017] Based on the above, the stress field at the wound edge can be reconstructed through mechanical output to inhibit scarring, such as... Figure 3 As shown in (b) above, the right side is a stress scale bar, specifically a single-dimensional color-value mapping bar with a value range of 0-1 (dimensionless, representing relative stress intensity). Red corresponds to a high value (1), and blue corresponds to a low value (0), used to quantify the differences in the intensity of stress distribution at the wound edge. For details, refer to... Figure 3 In (b), without the patch, the stress distribution at the wound edge is significantly non-uniform. The red area (peak relative stress intensity > 0.8) corresponds to the local stress concentration area at the wound edge, especially forming a continuous high-tension area at both ends of the wound edge (relative stress intensity stable at 0.6-0.8). This stress distribution easily leads to excessive activation of local myofibroblasts at the wound edge, thereby inducing abnormal collagen deposition. Figure 3 (c) demonstrates that after activation of the rotational shrinkage patch (Rt-MC), the peak stress decreases by >50%, and the high-stress area (red) is dispersed into a uniform medium-low stress area (blue-green). This dynamic redistribution stems from the offsetting effect of the patch's rotational shrinkage force on the circumferential and composite stresses at the wound edge, achieving the time-controlled goal of promoting early regeneration and inhibiting scarring in the later stages from a mechanical perspective.

[0018] Furthermore, the rapid closure and clinical operability of this invention were further confirmed using an in vitro model. Specifically, in a porcine circular wound model, the rotational contraction patch (Rt-MC) demonstrated excellent clinical translational potential. Figure 4 As shown in (d), TEG is the commercial dressing Tegaderm, which has breathable, waterproof, and antibacterial functions; RaC is a simple radial contraction patch; Rt-MC is a medium-tension rotational contraction patch; and Rt-HC is a high-tension rotational contraction patch. In the control group, the wound area increased to 110% within 20 minutes due to natural expansion, while in the Rt-MC group, the wound area was significantly reduced to 70% through rotational contraction force driving the wound edges to close centripetally. This process relies on strong wet adhesion (120 kPa) mediated by NHS esters, allowing for stable adhesion without sutures, and the mechanical response is activated within 20 seconds.

[0019] like Figure 5 As shown, the present invention also provides a method for preparing the above-mentioned programmable hydrogel wound dressing with rotational contraction force, comprising the following steps: S1. Mix polyvinyl alcohol solution with methacrylamide hyaluronic acid solution, add photoinitiator and acrylic acid-NHS, and complete photopolymerization by ultraviolet light irradiation to obtain wet double network hydrogel. S2. After pre-stretching or pre-twisting the wet dual-network hydrogel, dry it at 50~60℃ for 40~50 hours to form a shape memory structure, thereby obtaining the programmable hydrogel wound dressing.

[0020] Specifically, in S1, the photoinitiator is LAP, and the addition amount is 0.05~0.2wt%; the ultraviolet light wavelength is 365nm, and the irradiation time is 10~20s. In S2, the pre-stretching ratio Δλ is 15~50%, and the pre-torsion angle Δα is 30~45°.

[0021] Furthermore, this invention also provides a method for using the aforementioned programmable hydrogel wound dressing with rotational contraction force. The programmable hydrogel wound dressing is applied to the surface of a moist wound. After absorbing wound exudate, the programmable hydrogel wound dressing initiates shape recovery, delivering directional mechanical stimulation to the wound edges. This directional mechanical stimulation activates the YAP and TGF-β / Smad signaling pathways in the early stages of wound healing and reduces tension to inhibit myofibroblast activation in the later stages of healing. Figure 5 As shown in (a), this diagram divides the wound healing process into the inflammatory phase (corresponding to...). Figure 5 (a) shows the initial wound, the proliferation phase, and the remodeling phase (corresponding to...). Figure 5 The diagram (a) shows three distinct phases: the remodeling phase and the remodeling phase, and quantifies the dynamic tissue changes in each phase (e.g., the peak of fibroblast migration during the proliferative phase and the risk of collagen remodeling during the remodeling phase). This physiological process map provides a core basis for implementing phased programmable mechanical interventions with hydrogel dressings: in the early stage (proliferative phase), moderate tension (1.0–1.6 N) is output through rotational contraction force to activate regeneration signaling pathways, while in the late stage (remodeling phase), mechanical attenuation is used to inhibit fibrosis induced by persistent stress, thus verifying the necessity of dynamic mechanical strategies matching physiological needs at the temporal and spatial control level.

[0022] like Figure 5As shown in (b), Hippo refers to the Hippo signaling pathway, YAP refers to Yes-associated protein, TGF-β refers to transforming growth factor-β, Smad3 refers to Smad family protein 3, active indicates that the signaling pathway molecules are in a functionally activated state, and α-SMA refers to α-smooth muscle actin. This signaling pathway diagram, through dual fluorescent labeling (YAP nucleoplasmic distribution and Smad3 phosphorylation level), elucidates the precise regulation of fibroblast behavior by external rotational contractile forces: rotational stress, by altering cytoskeletal tension, simultaneously achieves YAP inhibition (reducing nuclear translocation rate >60%) and TGF-β / Smad3 activation (increasing phosphorylation level by 2.1 times). This mechanism demonstrates that the multidirectional mechanical output of hydrogel dressings can break the contradictory balance between regeneration and scar formation, and its rotational mode specificity is superior to traditional linear stretching, providing a molecular biological basis for the dual goals of early healing promotion and late scar inhibition. Figure 6 As shown in (c), the application model intuitively demonstrates the actual application state of the hydrogel patch after it is applied to the skin wound: the patch forms covalent bonds with the amino groups of wound tissue proteins through the NHS ester groups on its surface (adhesion strength reaches 120kPa), ensuring no risk of slippage in a moist environment; at the same time, its spiral structure outputs contraction force along the preset rotation direction (indicated by the arrow) after rehydration, evenly covering the wound edge area, effectively transmitting multi-directional mechanical stimulation to disperse high stress concentration points (such as the wound tip). This integrated design not only achieves precise transmission of mechanical force (such as rotational contraction force of 1.6N), but also adapts to different wound geometry features through customizable shapes (spiral, radial, or strip), solving the limitations of poor wet adhesion performance and non-programmable force field direction of traditional dressings. This further verifies that the adhesion-mechanical coupling mechanism supports rapid bedside operation (activation within 20 seconds) without the need for sutures or external fixation devices; combined with the pigskin experimental data shown in the figure (the wound area decreased by 30% after 20 minutes of patch treatment), it proves that it can effectively inhibit wound expansion and scar risk in real wound environments, providing an engineering basis for the dynamic regulation of the mechanical microenvironment.

[0023] In addition, the present invention also conducted performance tests on programmable hydrogel wound dressings, specifically including: like Figure 6 As shown in (b), this figure is the water absorption and swelling curve of the hydrogel, recording the change in the swelling rate of the hydrogel at different time points, intuitively reflecting its water absorption performance in an aqueous environment: as time goes on, the swelling rate of the hydrogel gradually increases and tends to stabilize, demonstrating its ability to quickly respond to wound exudate. This curve verifies the design of the hydrogel of this invention, which can absorb wound exudate and initiate shape recovery, providing performance evidence for its shape memory-driven operation in a moist wound environment. Figure 6As shown in (c), this figure illustrates the frequency response relationship between the storage modulus (G') and loss modulus (G'') of the modified hydrogel at different frequencies. Red and blue in the figure represent the test results for the unmodified and modified NHS hydrogels, respectively. The results show that the modulus performance of the modified NHS hydrogel in different frequency ranges is not significantly different from that of the unmodified hydrogel, indicating that the preparation of 1-3% wt NHS ester modification does not excessively affect the mechanical properties of the hydrogel. Figure 6 As shown in (d), this figure presents the tensile stress-strain curve of the hydrogel, revealing the differences in mechanical properties of the hydrogel with different component ratios, including key parameters such as fracture strength and elongation at break. The optimized dual-network structure hydrogel exhibits higher fracture strength and better ductility, enabling it to withstand mechanical stress during shape recovery. This result verifies the design of the dual-network structure in this invention, which provides sufficient mechanical support and lays the structural foundation for its effective mechanical force output to promote wound closure. Figure 6 As shown in (e), this figure illustrates the overlap shear test and the shear stress-displacement curves of the modified and unmodified hydrogels. Red and blue in the figure represent the shear stress changes of the unmodified and modified NHS hydrogels, respectively. The experimental results show that the modified NHS hydrogel exhibits significantly higher shear stress with a smaller shear displacement, indicating stronger mechanical strength and better adhesion properties. This characteristic allows the modified NHS hydrogel to provide more stable support and more effective adhesion when applied in wound repair. Figure 6 As shown in (f), this figure illustrates the shear experiment and the shear force-displacement curves of the modified and unmodified hydrogels. The red and blue curves represent the response force changes of the unmodified and modified NHS hydrogels under a 180° shear condition, respectively. The experimental results show that the modified NHS hydrogel exhibits a more stable mechanical response during shearing, especially at larger displacements, where the shear force of the modified hydrogel is significantly higher than that of the unmodified hydrogel, and the mechanical response fluctuation is smaller. This indicates that the modified NHS hydrogel possesses excellent shear resistance and can provide more reliable structural stability in wound repair applications. Figure 6 Figure (g) shows a schematic diagram of the tensile test and the tensile stress-displacement curves of the modified and unmodified hydrogels. The blue and red curves represent the stress changes of the unmodified and modified NHS hydrogels during the tensile process, respectively. The experimental results show that the modified NHS hydrogel exhibits significantly higher tensile stress during the tensile process, especially at larger displacements, where the tensile strength of the modified hydrogel is significantly better than that of the unmodified hydrogel. This characteristic enables the modified NHS hydrogel to possess higher tensile strength in wound repair applications, effectively enhancing the mechanical support during wound healing.

[0024] like Figure 6As shown in (h), this figure presents the test results for interfacial shear force and tensile force. The red circles represent interfacial shear force, and the blue hollow circles represent tensile force. The experimental results show that there is no significant difference (ns) between the modified NHS hydrogel and the unmodified hydrogel in terms of interfacial shear force and tensile force; their mechanical properties remain relatively consistent. This indicates that although the modified NHS hydrogel exhibits better performance in some mechanical tests, its interfacial adhesion and tensile force are comparable to the unmodified hydrogel, demonstrating strong adaptability and the ability to meet the needs of different application scenarios. Figure 6 As shown in (i), ASTM F2255 is the American Society for Testing and Materials (ASTM) standard for testing the adhesive strength of soft tissue repair materials, ASTM F2256 is the ASTM standard for testing the tissue adhesion shear properties of medical materials, and ASTM F2458-05 is the ASTM standard for evaluating the performance of medical adhesives, 2005 edition. This figure shows the results of the overlap shear test, demonstrating the shear stress test results for different tissue types. The red bars in the figure represent skin tissue, and the other colored bars represent heart, liver, kidney, and bone tissue, respectively. The experimental results show that the hydrogel patch has strong adhesion to various organs, with the highest adhesion shear stress in skin tissue, reaching approximately 90 kPa. This result indicates that the hydrogel used in this study has high tissue adhesion ability and can provide good adhesive support in skin wound repair. Figure 7 As shown in (j) of the figure, this figure presents the results of the shear experiment, demonstrating the interfacial adhesion strength test results of different tissue types under 180° shear conditions. The red bars in the figure represent skin tissue, while the other colored bars represent heart, liver, kidney, and bone tissues, respectively. The experimental results show that the interfacial adhesion strength of skin tissue is significantly higher than that of other tissues, reaching approximately 300 J / m², while the interfacial adhesion strength of other tissues also reached a high level. This result indicates that the hydrogel in this study has significant advantages in interfacial adhesion performance with various tissues and is suitable for applications in wound repair. Figure 7 As shown in (k), where " "Statistically significant differences are indicated by the numbers '[']'. This figure shows the results of a wound closure experiment, illustrating the difference in wound closure force between modified NHS hydrogel and other comparative materials (such as medical tape, gauze, and Tegaderm). The red bars represent modified NHS hydrogel, while the blue, black, and yellow bars represent other materials, respectively. The experimental results show that modified NHS hydrogel exhibits a significant advantage in wound closure force, approximately 6 N, which is significantly higher than other comparative materials, and this difference is statistically significant. This result indicates that modified NHS hydrogel can provide stronger closure force during wound repair and has greater potential for clinical application."

[0025] To further verify the application of the programmable hydrogel wound dressing with rotational contraction force of the present invention in regulating the wound microenvironment and promoting scarless healing, specific animal experiments are conducted below for further explanation.

[0026] First, the programmable hydrogel wound dressing of this invention was applied to a diabetic mouse model to evaluate its wound healing effect. The results are as follows: Figure 7 As shown. (Refer to...) Figure 7 Figure (a) shows representative wound photographs and numerical analysis results on days 0, 4, 8, and 16 of a 5mm full-thickness skin defect model on the back of diabetic mice. The results visually demonstrate the differences in wound closure processes among the groups: the TEG group (using commercially available Tegaderm dressing with breathable, waterproof, and antibacterial properties), the RaC group (simple radial contraction patch), the Rt-HC group (high-tension rotational contraction patch), and the Rt-MC group (medium-tension rotational contraction patch). The Rt-MC group showed significantly faster wound closure over time compared to the other groups, especially on days 8 and 16, exhibiting better wound integrity. This result directly reflects the promoting effect of the hydrogel wound dressing of this invention on chronic wound repair, providing macroscopic evidence for its effect in regulating the wound microenvironment.

[0027] Reference Figure 7 Figure (b) shows the quantitative results of wound area changes over time in different treatment groups. The data curves clearly present the wound healing rate of each group: the wound area of ​​the Rt-MC group was smaller than that of the control group and other modality groups at all time points, and the wound closure rate on day 16 reached 83.4% ± 3.1%, significantly higher than that of the TEG group (48.2% ± 5.6%). This quantitative data further verifies the advantage of hydrogel dressings with moderate rotational contraction in promoting wound closure efficiency and supports its effective regulation of the wound microenvironment. (Refer to...) Figure 8 Figure (c) shows the H&E staining results of wound tissues from different treatment groups on days 8 and 16, including a magnified view of the re-epithelialization front, revealing the microstructure of tissue regeneration: the Rt-MC group showed better epidermal continuity, more orderly dermal cell arrangement, more pronounced advancement of the re-epithelialization front, and less inflammatory cell infiltration. This result, from a histological perspective, demonstrates that the dressing of this invention can improve the wound microenvironment, promote orderly tissue regeneration, and lay the foundation for scarless healing. (Refer to...) Figure 9 Figure (d) shows the quantitative analysis data of the degree of wound re-epithelialization in different treatment groups. The integrity of epidermal regeneration in each group was compared using statistical methods: the Rt-MC group achieved re-epithelialization rates of 65% and 92% on days 8 and 16, respectively, significantly higher than other groups. This data intuitively reflects that the hydrogel dressing of this invention effectively promotes epidermal regeneration and wound re-epithelialization by regulating the wound microenvironment, further confirming its application value in promoting scarless healing.

[0028] Secondly, the programmable hydrogel wound dressing of the present invention was applied under the control of a rotational shrinkage hydrogel patch to regulate the wound healing mechanism, and the results were as follows. Figure 8 and Figure 9 As shown, Masson's trichrome staining results of wound tissues from different treatment groups on days 8 and 16 revealed the distribution and arrangement of collagen fibers: the collagen fibers in the Rt-MC group (moderate rotational contraction mode) were more regularly arranged and evenly distributed, more closely resembling the collagen structure of normal tissue, while the control group and other groups showed disordered collagen arrangement and uneven deposition. This result directly demonstrates that the hydrogel dressing of this invention can improve the collagen remodeling process by regulating the wound microenvironment, providing histological evidence for promoting scarless healing.

[0029] Furthermore, markers such as CD31, α-SMA, DAPI, TGF-β, and YAP were used to demonstrate angiogenesis, fibroblast activity, and the expression of related signaling pathway molecules: the Rt-MC group showed a higher number of CD31-positive vessels, lower α-SMA expression (suggesting suppressed myofibroblast activation), and nuclear translocation of TGF-β and YAP more aligned with the needs of different stages of wound healing. This image reveals the mechanism by which hydrogel dressings regulate the wound microenvironment at the cellular and molecular levels, supporting its dual effect of promoting tissue regeneration and inhibiting scar formation. (Reference) Figure 10 (a), (b), (c) and Figure 11 As shown in (a), (b), and (c), these figures present quantitative analysis data of IL-6, TNF-α, CD31, α-SMA, TGF-β, and YAP. Statistical methods were used to compare the differences in molecular expression among different treatment groups: the Rt-MC group showed significantly lower levels of pro-inflammatory factors IL-6 and TNF-α, higher CD31-positive vessel density, lower α-SMA expression, and TGF-β and YAP expression and activation levels were more conducive to wound healing. These quantitative results further validate that hydrogel dressings can optimize the wound microenvironment by regulating inflammatory responses, promoting angiogenesis, and modulating key signaling pathways, providing strong molecular-level support for its technical efficacy in promoting scarless healing.

[0030] Finally, the programmable hydrogel wound dressing of this invention was applied to a rabbit ear hypertrophic scar model for long-term evaluation of scar remodeling and tissue regeneration. The results are as follows: Figure 10 and Figure 10 As shown. (Refer to...) Figure 10Figure (a) shows the wound healing appearance of each treatment group in the rabbit ear hypertrophic scar model at weeks 0, 2, 4, 6, and 8, visually demonstrating the long-term changes in scar formation: the Rt-MC group (moderate rotational contraction pattern) showed significantly lower scar hyperplasia than the control group and other pattern groups, especially at weeks 6-8, where the scar color was closer to normal skin and the elevation was less pronounced. This result directly demonstrates the role of the hydrogel dressing of this invention in long-term inhibition of scar formation, providing macroscopic evidence for its regulation of the wound microenvironment to promote scarless healing. Figure 11 As shown in (b), this figure presents the H&E staining results of wound tissues from different treatment groups at weeks 4 and 8, revealing differences in dermal structure repair and scar thickness: the dermal structure of the Rt-MC group was closer to normal tissue, the scar thickness was significantly thinner than the control group, and there was less inflammatory cell infiltration. This histological result validates that hydrogel dressings can improve the wound microenvironment, reduce abnormal tissue proliferation, and support its technical effect of inhibiting scar formation. Figure 11 As shown in (c), this figure presents the Masson trichrome staining results of wound tissues from different treatment groups, demonstrating the distribution and regularity of collagen fibers: the collagen fibers in the Rt-MC group were more orderly and oriented, similar to the collagen structure of normal skin, while the collagen fibers in the control group were disordered and intertwined. This result demonstrates the optimizing effect of hydrogel dressings on the wound microenvironment from the perspective of collagen remodeling, providing a structural basis for scarless healing. Figure 11 As shown in (a), this figure presents the results of SiriusRed staining under polarized light, reflecting the maturity of collagen fibers and the orderliness of tissue structure: the ratio of type I to type III collagen in the Rt-MC group is closer to that of normal tissue, and the direction of collagen fibers is more regular, while the collagen maturity in the control group is lower and the arrangement is disordered. This result further confirms that hydrogel dressings can promote normal collagen maturation and arrangement by regulating the wound microenvironment, which helps to reduce scar formation.

[0031] like Figure 12 As shown in (b) of the figure, this figure presents the quantitative analysis results of CD31 signal intensity, reflecting the status of wound angiogenesis: the CD31-positive vessel density in the Rt-MC group was closer to normal levels in the later stages of healing, ensuring both the blood supply required for tissue repair and avoiding scar hyperplasia caused by excessive vascularization. This result reveals the mechanism by which hydrogel dressings optimize the wound microenvironment by regulating angiogenesis, contributing to an understanding of its mechanism of action in inhibiting scarring. Figure 13As shown in (c), this figure presents the quantitative analysis results of α-SMA signal intensity, reflecting the degree of myofibroblast activation: the α-SMA expression level in the Rt-MC group was significantly lower than that in the control group, especially in weeks 4-8, indicating that myofibroblast activation was effectively inhibited. This result explains the mechanism by which hydrogel dressing inhibits scar formation at the cellular level, namely, by regulating the wound microenvironment to reduce excessive proliferation and contraction of myofibroblasts, thereby reducing the risk of scar hyperplasia.

[0032] In addition, this invention also provides transcriptomic analysis revealing the molecular mechanism by which hydrogel patches promote healing and reduce scarring through mechanical regulation, as shown in the following results. Figure 14 , Figure 15 , Figure 12 and Figure 12 As shown. Among them, in Figure 12 In (a) and (b), Log2FPKM is the logarithmically mapped reading per kilobase exon per million fragments, used to quantify gene expression levels; log2FC is the logarithmically fold change in expression, used to measure the degree of difference in gene expression between two groups, with positive values ​​indicating "upregulated gene (UP)" and negative values ​​indicating "downregulated gene (DOWN)"; -log 10 (Adjusted P-value) is the negative logarithm of the adjusted P-value, used to assess the statistical significance of the difference; Padj is the adjusted P-value, used to exclude false positives from multiple tests; NOT represents genes with no significant difference. (Refer to...) Figure 13 Figure (a) shows a circular heatmap of whole-gene expression in wound tissue at week 4, illustrating the differences in gene expression among different treatment groups (such as the Rt-MC group, RaC group, and control group). The color intensity visually represents the level of gene expression: the Rt-MC group (moderate rotational contraction pattern) exhibited a specific expression pattern in gene clusters related to wound healing, collagen metabolism, and inflammation regulation, significantly distinguishing it from other groups. This result reveals the molecular basis of hydrogel dressings regulating the wound microenvironment at the genomic level, providing broad-spectrum gene expression evidence for its role in promoting scarless healing. (See reference...) Figure 14 Figure (b) shows a differential gene volcano plot between the Rt-MC and RaC groups, presenting significant differences in gene expression between the two groups in a scatter plot format: red dots represent significantly upregulated genes, and blue dots represent significantly downregulated genes. Genes related to the TGF-β and Hippo-YAP pathways show markedly different expression. This plot precisely locates key regulatory genes under different mechanical modes, providing target references for elucidating the molecular mechanism by which hydrogel dressings influence scar formation through specific mechanical stimulation.

[0033] Among them, Figure 13In the vertical axis, biological processes (BP) include: multicellular organism development; skeletal system development; animal organ morphogenesis; tissue development; system development; regulation of cellular response to growth factor stimulation; anatomical structure morphogenesis; animal organ development; cartilage development; and collagen fiber organization. Molecular functions (MF) include: calcium ion binding; extracellular matrix structural constituent; integrin binding; procollagen-proline dioxygenase activity; cell adhesion molecule binding; peptidyl-proline dioxygenase activity; frizzled binding; and signaling receptor. Binding refers to signal receptor binding; chemoattractant activity refers to chemical attraction activity; organic acid binding refers to organic acid binding; cellular components (CC) include: extracellular matrix; external encapsulating structure; collagen trimer; extracellular region; collagen-containing extracellular matrix; cell periphery; FACIT collagen trimer.Extracellular space refers to the intercellular space; microfibril refers to microfibrils; fibrillar collagen trimer refers to fibrous collagen trimers. Gene number refers to the number of differentially expressed genes involved in a given GO term; Rich Factor is the enrichment factor, the ratio of the number of differentially expressed genes involved in a particular GO term to the number of background genes involved in that GO term; a higher value indicates a higher degree of enrichment for that GO term; -log10(p.value) is the negative logarithm of the p-value, used to indicate the statistical reliability of the enrichment results. Figure 13In the vertical axis, ECM-receptor interaction refers to extracellular matrix-receptor interaction, which participates in the binding of the extracellular matrix to cell surface receptors and regulates processes such as cell adhesion and migration; Focal adhesion is a key structure for cell-extracellular matrix adhesion, participating in mechanotransduction and signal transduction; TGF-beta signaling pathway plays a core regulatory role in cell proliferation, differentiation, apoptosis, and tissue repair; PI3K-Akt signaling pathway participates in various biological processes such as cell survival, proliferation, and metabolism; Cell cycle is the cyclical process of cell division from the end of one division to the end of the next, regulating cell proliferation; Regulation of actin cytoskeleton is the regulation of actin cytoskeleton, as actin is an important component of the cytoskeleton, and its dynamic regulation affects cell morphology, movement, and signal transduction; Proteoglycans in Cancer refers to proteoglycans in cancer, which play a role in tumorigenesis, invasion, and metastasis; Malaria is a disease caused by Plasmodium infection, involving infection-related molecular mechanisms; Human papillomavirus infection is related to viral carcinogenesis; Hippo signaling pathway regulates cell proliferation, apoptosis, and organ size, and is closely related to tissue regeneration and tumorigenesis; Hippo signaling pathway-multiple species analyzes the conservation of the Hippo pathway in different species; Complement and coagulation cascades participate in immune defense and hemostasis; Biosynthesis of nucleotide sugars is the biosynthesis of nucleotide sugars, which are precursors for processes such as glycosylation; Staphylococcus aureus infection is a signaling pathway related to bacterial infection; Melanoma is a type of skin cancer involving molecular mechanisms of tumorigenesis; Amoebiasis is an infectious disease caused by amoebae; Cocaine Addiction refers to cocaine addiction and the neurobiological pathways associated with addiction; Regulation of lipolysis in adipocytes refers to the regulation of lipolysis in adipocytes, specifically the process of regulating triglyceride breakdown in adipocytes.Gastric cancer refers to stomach cancer. The molecular pathways involved in the development and progression of gastric cancer are as follows: Figure 14 Maintain consistency.

[0034] Reference Figure 15 and ​ These two figures, GO enrichment analysis and KEGG pathway analysis, respectively, focus on the biological processes and signaling pathways involved in differentially expressed genes: GO analysis showed that differentially expressed genes were mainly enriched in processes such as ECM remodeling and collagen fiber assembly; KEGG analysis highlighted the significant activation of the TGF-β and Hippo-YAP signaling pathways. These results elucidate the core molecular pathways by which hydrogel dressings regulate the wound microenvironment at the functional level, supporting the technical principle of its influence on cell behavior through mechanical stimulation. (Refer to...) ​ Figures (a), (b), and (c) show immunofluorescence images and quantitative results of TGF-β and YAP, illustrating changes in protein expression and localization: In the Rt-MC group, TGF-β expression was moderate in the early stage of wound healing to promote regeneration, and gradually downregulated in the later stage to reduce scarring; the nuclear translocation rate of YAP showed phased changes, matching the temporal regulation of mechanical stimulation, and quantitative data showed that its expression level was negatively correlated with the scar inhibition effect. These results validated the activation mode of key signaling pathways at the protein level, directly confirming the molecular mechanism by which hydrogel dressings optimize the wound microenvironment by regulating the TGF-β / YAP pathway.

[0035] Therefore, by employing the aforementioned programmable hydrogel wound dressing with rotational contraction force and its application, dynamic and accurate control of wound edge stress can be achieved through the construction of a dual-network hydrogel structure and an NHS ester-functionalized surface. Simultaneously, it can output mechanical force with controllable direction and adjustable intensity according to the wound shape and healing stage, maintaining excellent tissue adhesion while taking into account the dual effects of promoting early regeneration and inhibiting late-stage scarring, thus solving the problems of passivity, singularity, and instability in wet environments of existing technologies.

Claims

1. A programmable hydrogel wound dressing with rotational contraction force, characterized in that, include: The dual-network hydrogel body is composed of a first network and a second network; the first network is a chemically cross-linked methacrylamide hyaluronic acid network, which forms a cross-linked network structure through photopolymerization; the second network is a physically cross-linked polyvinyl alcohol network, which forms instantaneous cross-linking points with crystalline regions through hydrogen bonds, giving the hydrogel shape memory properties. The surface of the dual-network hydrogel host is modified with N-hydroxysuccinimide ester functional groups, which can form covalent bonds with the amino groups of wound tissue proteins; The dual-network hydrogel body is dried and shaped into a preset shape after pre-stretching or pre-torsion treatment. After absorbing water, it restores its initial shape and outputs mechanical force for rotational contraction.

2. The programmable hydrogel wound dressing with rotational contraction force according to claim 1, characterized in that, The concentration of methacrylamide hyaluronic acid in the first network is 3-5 vol%, and the concentration of polyvinyl alcohol in the second network is 8-12 wt%.

3. The programmable hydrogel wound dressing with rotational contraction force according to claim 1, characterized in that, The N-hydroxysuccinimide ester functional group is achieved by introducing an acrylic acid-NHS comonomer, wherein the amount of acrylic acid-NHS added is 1~3wt%.

4. The programmable hydrogel wound dressing with rotational contraction force according to claim 1, characterized in that, The preset shape includes one or more of spiral, radial, and strip shapes, and the corresponding output mechanical force mode includes one or more of radial contraction, rotational contraction, and tension relief.

5. A method for preparing a programmable hydrogel wound dressing with rotational contraction force according to any one of claims 1 to 4, characterized in that, Includes the following steps: S1. Mix polyvinyl alcohol solution with methacrylamide hyaluronic acid solution, add photoinitiator and acrylic acid-NHS, and complete photopolymerization by ultraviolet light irradiation to obtain wet double network hydrogel. S2. After pre-stretching or pre-twisting the wet dual-network hydrogel, dry it at 50~60℃ for 40~50 hours to form a shape memory structure, thereby obtaining the programmable hydrogel wound dressing.

6. The method for preparing a programmable hydrogel wound dressing with rotational contraction force according to claim 5, characterized in that, In S1, the photoinitiator is LAP, and the addition amount is 0.05~0.2wt%; the ultraviolet light wavelength is 365nm, and the irradiation time is 10~20s.

7. The method for preparing a programmable hydrogel wound dressing with rotational contraction force according to claim 5, characterized in that, In S2, the pre-stretch ratio Δλ is 15~50%, and the pre-torsion angle Δα is 30~45°.

8. A method of using a programmable hydrogel wound dressing with rotational contraction force according to any one of claims 1 to 4, characterized in that, The programmable hydrogel wound dressing is applied to the surface of a moist wound. After absorbing the exudate from the wound, the programmable hydrogel wound dressing initiates shape recovery and outputs directional mechanical stimulation to the wound edge.

9. The method of using a programmable hydrogel wound dressing with rotational contraction force according to claim 8, characterized in that, The directional mechanical stimulation activates the YAP and TGF-β / Smad signaling pathways in the early stage of wound healing and reduces tension in the later stage of healing to inhibit myofibroblast activation.

10. An application of a programmable hydrogel wound dressing with rotational contraction force according to any one of claims 1 to 4, characterized in that, Specifically, it is used to regulate the wound microenvironment and promote scarless healing.

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