Platinum-doped composite hydrogel, preparation method thereof and wearable electronic device

Abstract

This application relates to the field of materials technology, providing a platinum-doped composite hydrogel and its preparation method, as well as a wearable electronic device. The platinum-doped composite hydrogel of this application employs a one-step freeze-thaw crosslinking process, free of toxic reagents, with a simple and controllable process. The hydrogel uses polyvinyl alcohol and sodium lignosulfonate as the matrix, exhibiting excellent biocompatibility and good hydrophilicity. It can absorb wound exudate and maintain a moist healing environment, and can stably produce hydrogen even at low voltage. The wearable electronic device of this application uses this hydrogel as an electrode, offering good fit, non-invasive safety, and enabling non-invasive long-term wear and real-time monitoring of wound status, dynamically reflecting inflammation levels. Through closed-loop control, it automatically starts and stops electrocatalytic therapy, producing hydrogen on demand and avoiding excessive intervention. The device boasts high overall integration, portability, and ease of use, effectively promoting wound healing and suitable for long-term care of chronic wounds such as those caused by diabetes. It balances safety and practicality, achieving precise and intelligent wound management.

Description

Technical Field

[0001] This application belongs to the field of materials technology, and in particular relates to a platinum-doped composite hydrogel and its preparation method, as well as wearable electronic devices. Background Technology

[0002] Diabetes mellitus, a prevalent chronic metabolic disease, continues to see a global increase in its prevalence. Diabetic wounds (typically diabetic foot ulcers) are among the most serious and common chronic complications of diabetes, often leading to prolonged wound healing, significantly reducing patients' quality of life and posing high health risks. Influenced by pathological factors such as a high-glucose microenvironment, local tissue ischemia and hypoxia, immune dysfunction, and a tendency for recurrent infections, diabetic wounds are difficult to heal and have a long healing cycle, with conventional treatments often failing to achieve ideal healing outcomes. Against this backdrop, hydrogel materials, with their excellent biocompatibility, ability to maintain a moist healing environment, tunable structure, and ease of functional modification, have shown great potential in the field of diabetic wound repair. Currently, researchers have developed angiogenic hydrogels, antioxidant hydrogels, anti-inflammatory hydrogels, antibacterial hydrogels, and multifunctional composite hydrogels to improve the microenvironment of diabetic wounds and promote wound healing.

[0003] However, most existing hydrogel-based wound dressings are either inherently functional or drug-loaded release types, resulting in a generally static and passive treatment approach. After application, they only continuously release active ingredients and cannot sense dynamic changes in the wound microenvironment or implement real-time responses and intelligent regulation. Such treatment strategies, lacking feedback and adaptive adjustment mechanisms, are ill-suited to the complex, dynamic, and variable healing process of diabetic wounds, limiting treatment precision and effectiveness. Summary of the Invention

[0004] The purpose of this application is to provide a platinum-doped composite hydrogel, which aims to solve the problem that existing hydrogel dressings are mostly static and passively released, unable to achieve active, on-demand, and precise intervention according to the dynamic changes in the wound microenvironment, and difficult to adapt to the complex and ever-changing healing process of diabetic wounds.

[0005] The embodiments of this application are implemented as follows: a method for preparing a platinum-doped composite hydrogel includes: Sodium lignosulfonate and polyvinyl alcohol were dissolved in a phosphate buffer solution and subjected to one freeze-thaw cycle to obtain a sodium lignosulfonate / polyvinyl alcohol hydrogel; the total mass fraction of sodium lignosulfonate and polyvinyl alcohol was 3-10 wt%. Prepare a platinum source solution containing potassium chloroplatinate and a reducing solution containing ascorbic acid, controlling the concentration of potassium chloroplatinate to be 10~100mM and the concentration of ascorbic acid to be 5~200mM; The obtained sodium lignosulfonate / polyvinyl alcohol hydrogel was sequentially immersed in the platinum source solution and the reduction solution. Platinum nanoparticles were loaded inside the hydrogel through in-situ reduction. After washing, a platinum-doped composite hydrogel was obtained.

[0006] Another objective of this application is to provide a platinum-doped composite hydrogel prepared by the above-described preparation method.

[0007] Another objective of this application is to apply the above-mentioned platinum-doped composite hydrogel in the preparation of electrically driven wound care materials. The platinum-doped composite hydrogel generates active hydrogen through electrocatalysis under external voltage driving, thereby achieving wound anti-inflammatory, antibacterial and wound healing promotion.

[0008] Another objective of this application is to provide a wearable electronic device, including a temperature acquisition module, flexible electrodes, and a voltage control module electrically connected to both the temperature acquisition module and the flexible electrodes; wherein... The temperature acquisition module is used to acquire the temperature signal of the wound site in real time; The flexible electrode is a hydrogel electrode formed using the above-mentioned platinum-doped composite hydrogel. The hydrogel electrode can generate active hydrogen in situ under voltage drive, thereby achieving anti-inflammatory, antibacterial, and wound-healing functions. The voltage control module is used to determine whether to activate the electrocatalytic treatment of the flexible electrode based on the temperature signal.

[0009] Another objective of this application is to apply the above-mentioned wearable electronic device in wound care, temperature monitoring, and electrocatalytic hydrogen production.

[0010] The platinum-doped composite hydrogel prepared in this application employs a one-step freeze-thaw physical crosslinking and in-situ reduction process. The preparation conditions are mild, require no toxic chemical crosslinking agents, and the process is simple, controllable, reproducible, and easily scalable. The sodium lignosulfonate raw material used is widely available and low in cost, effectively improving the dispersion stability and structural uniformity of the hydrogel. This hydrogel, based on polyvinyl alcohol and sodium lignosulfonate, exhibits excellent biocompatibility and hydrophilicity, capable of absorbing wound exudate and maintaining a moist healing environment. The in-situ loaded platinum nanoparticles are uniformly distributed, firmly bonded, and not easily leaked, achieving efficient and stable electrocatalytic hydrogen production under low voltage, combining good biosafety with electrocatalytic function.

[0011] Furthermore, the wearable electronic device constructed in this application uses the aforementioned platinum-doped composite hydrogel as a flexible electrode. Its soft, deformable, and highly conformable texture allows it to closely fit irregular wound surfaces, enabling non-invasive, comfortable, and long-term wear. A temperature acquisition module can continuously monitor wound temperature 24 hours a day, dynamically reflecting inflammation levels and providing a basis for assessing healing status. Combined with closed-loop feedback control logic, it can automatically start and stop electrocatalytic therapy based on temperature changes, achieving on-demand hydrogen production and intelligent start-stop, avoiding excessive intervention and improving treatment safety and efficiency. The device features high overall integration, flexibility, wearability, low power consumption, portability, and ease of use. It can exert multiple effects through in-situ electrocatalytic hydrogen production, including anti-inflammatory, antioxidant, antibacterial, and promotion of angiogenesis and granulation tissue growth, significantly accelerating the healing of chronic wounds such as those caused by diabetes, making it suitable for long-term intelligent home care. Attached Figure Description

[0012] Figure 1 (a) compressive stress-strain curves of LS / PVA hydrogels with different ratios provided for embodiments of this application; (b) tensile stress-strain curves of LS / PVA hydrogels with different ratios. Figure 2 (a) SEM image of LS / PVA hydrogel; (b) SEM image of Pt@LS / PVA hydrogel provided for embodiments of this application; Figure 3 X-ray diffraction patterns of LS / PVA hydrogel and Pt@LS / PVA hydrogel provided in the embodiments of this application; Figure 4 (a) Full X-ray photoelectron spectroscopy (XPS) spectra of LS / PVA hydrogel and Pt@LS / PVA hydrogel provided for embodiments of this application; (b) Fine XPS spectra of LS / PVA hydrogel and Pt@LS / PVA hydrogel. Figure 5 (a) the electrical conductivity of a series of Pt@LS / PVA hydrogels provided for embodiments of this application; (b) an optical image of a Pt@LS / PVA hydrogel illuminating an LED indicator. Figure 6 Different hydrogels provided in the embodiments of this application induce a decolorization reaction of MB under neutral conditions; Figure 7 The embodiments of this application provide (a) colorimetric reactions of ABTS induced by different hydrogels under neutral conditions; (b) colorimetric reactions of Pt@LS / PVA hydrogels under different voltages (all times were 30 min). Figure 8The following are provided for the embodiments of this application: (a) flow cytometry analysis results of the number of M1 / M2 macrophages in different groups; (b) quantitative statistics of the population ratio of M1 macrophages and M2 macrophages in different groups (n = 3, ns indicates no significant difference, ** indicates p < 0.001, *** indicates p < 0.0001); Groups: (1) IL-4, (2) LPS, (3) LPS + Pt@LS / PVA hydrogel, (4) LPS + LS / PVA hydrogel + ES, (5) LPS + Pt@LS / PVA hydrogel + ES; Figure 9 (a) Agar plate images (MRSA) of different groups provided for embodiments of this application; (b) Survival rates of MRSA in different groups (n = 3, ns indicates no significant difference, ** indicates p < 0.001, *** indicates p < 0.0001). Figure 10 Images of NIH / 3T3 cell proliferation and migration provided for embodiments of this application; Figure 11 Cytotoxicity of the Pt@LS / PVA hydrogel provided in the embodiments of this application (n=3); Figure 12 HUVEC cell live / dead counterstaining fluorescence image provided for embodiments of this application (scale bar = 200 μm); Figure 13 Component diagrams of flexible electronic devices provided in embodiments of this application; Figure 14 (a) A schematic diagram of the thickness of the sensing / electrode system provided for embodiments of this application; (b) A schematic diagram of the flexible electronic device being worn; Figure 15 (a) A system block diagram of the flexible electronic device provided for embodiments of this application; (b) A flowchart of the control program execution of the flexible electronic device; Figure 16 (a) Temperature monitoring of flexible electronic devices and thermal imagers provided for embodiments of this application; (b) Output voltage changes of devices under rapid temperature changes; Figure 17 This is a flowchart of diabetic wound treatment provided in an embodiment of this application; Figure 18 (a) Wound images of diabetic mice in each group within 14 days; (b) Wound healing trajectory of diabetic mice in each group within 14 days; (c) Wound temperature monitoring data of mice during treatment provided for embodiments of this application; Figure 19 The relative wound area of ​​each group of diabetic mice within 14 days provided in the embodiments of this application (n=3). Figure 20 H&E staining and Masson staining of wound skin tissue from diabetic mice on day 14 provided in this application embodiment; Figure 21 CD31 immunofluorescence staining image of a wound in a diabetic mouse on day 14 provided in this application embodiment (scale bar = 50 μm). Figure 22 Immunofluorescence staining image of CD86 / CD206 in a diabetic mouse wound on day 7, provided for an embodiment of this application (scale bar = 50 μm). Figure 23 The curves showing the change in body weight of mice in each group provided in the embodiments of this application; Figure 24 H&E staining of major organs (heart, liver, spleen, lung, kidney) of mice in different groups provided in the embodiments of this application (scale bar = 100 μm). Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0014] This application provides a method for preparing a platinum-doped composite hydrogel, comprising: Sodium lignosulfonate and polyvinyl alcohol were dissolved in a phosphate buffer solution and subjected to one freeze-thaw cycle to obtain sodium lignosulfonate / polyvinyl alcohol hydrogel (LS / PVA hydrogel); a platinum source solution containing potassium chloroplatinate and a reducing solution containing ascorbic acid were prepared, with the concentration of potassium chloroplatinate controlled at 10~100mM and the concentration of ascorbic acid controlled at 5~200mM. The obtained sodium lignosulfonate / polyvinyl alcohol hydrogel was sequentially immersed in the platinum source solution and the reduction solution. Platinum nanoparticles were loaded inside the hydrogel through in-situ reduction. After washing, a platinum-doped composite hydrogel (Pt@LS / PVA hydrogel) was obtained.

[0015] Preferably, the total mass fraction of sodium lignosulfonate and polyvinyl alcohol is 3-10 wt%, more preferably 5 wt%.

[0016] Preferably, the step of dissolving sodium lignosulfonate and polyvinyl alcohol in a phosphate buffer solution and subjecting it to a freeze-thaw cycle to obtain sodium lignosulfonate / polyvinyl alcohol hydrogel includes: fully dissolving sodium lignosulfonate and polyvinyl alcohol in a phosphate buffer solution at 90-95°C to form a homogeneous mixed solution; subjecting the mixed solution to a freeze-thaw cycle at -20°C for 36-48 hours, and then restoring it to room temperature to obtain sodium lignosulfonate / polyvinyl alcohol hydrogel.

[0017] Preferably, the preparation of the platinum source solution containing potassium chloroplatinate and the reducing solution containing ascorbic acid includes: using a phosphate buffer solution to prepare a polyvinylpyrrolidone solution as a solvent, preparing the platinum source solution containing potassium chloroplatinate and the reducing solution containing ascorbic acid, and controlling the concentration of potassium chloroplatinate to be 100 mM and the concentration of ascorbic acid to be 100 mM.

[0018] This application also provides a platinum-doped composite hydrogel prepared by the above method. It uses a sodium lignosulfonate / polyvinyl alcohol interpenetrating network as a matrix, with platinum nanoparticles grown in situ and uniformly loaded inside. It has high porosity, high specific surface area, good hydrophilicity, biocompatibility and conductivity. It can efficiently electrocatalyze the generation of active hydrogen under low voltage drive, and also has the characteristics of flexibility, stretchability and good interfacial adhesion.

[0019] This application also provides an electrocatalytic wound care application of the above-mentioned hydrogel. The platinum-doped composite hydrogel can be used as an electrocatalytic functional material to prepare electrically driven wound care dressings or flexible electrodes. Under a low voltage drive of 0-3V, it generates active hydrogen in situ, gently and continuously at the wound interface. By scavenging reactive oxygen species, inhibiting inflammatory factors, regulating macrophage phenotype, inhibiting pathogenic bacteria in the wound, and promoting granulation tissue and angiogenesis, it achieves anti-inflammatory, antibacterial, antioxidant, and wound healing care effects.

[0020] This application also provides a wearable electronic device, characterized in that it includes a temperature acquisition module, a flexible electrode, and a voltage control module electrically connected to both the temperature acquisition module and the flexible electrode; wherein... The temperature acquisition module is used to acquire the temperature signal of the wound site in real time; The flexible electrode is a hydrogel electrode formed using the above-mentioned platinum-doped composite hydrogel. The hydrogel electrode can generate active hydrogen and active chlorine in situ under voltage drive, thereby achieving anti-inflammatory, antibacterial, and wound-healing functions. The voltage control module is used to determine whether to activate the electrocatalytic treatment of the flexible electrode based on the temperature signal.

[0021] Preferably, the voltage control module is configured to: automatically output a preset voltage to power the flexible electrode when the wound temperature collected by the temperature acquisition module exceeds a preset threshold, and drive the electrode to electrocatalyze the generation of hydrogen and active chlorine within a preset time; and automatically shut off the output voltage when the wound temperature returns to a normal level, so that the device can realize the functions of continuous temperature monitoring, real-time intelligent response and closed-loop feedback.

[0022] Preferably, the above-mentioned device is composed of a temperature acquisition module, a flexible hydrogel electrode, a voltage control module, a display module, and a power supply module integrated on a flexible substrate. Temperature acquisition module: It adopts a flexible temperature sensor that is directly attached to the wound or skin surface to continuously, in real time and with high precision acquire temperature signals, reflecting the degree of wound inflammation and healing status; Flexible electrode: It is formed by the above-mentioned platinum-doped composite hydrogel, which has high biocompatibility, high electrocatalytic activity and high flexibility. It can closely fit the wound interface and efficiently generate active hydrogen under low voltage. Voltage control module: This is a low-power microcontroller unit that presets temperature threshold, output voltage, and operating time. It receives temperature signals and performs logical judgments. When the temperature exceeds the threshold, it automatically outputs voltage to start electrocatalysis. When the temperature returns to normal, it immediately shuts off the voltage to stop hydrogen production, thus achieving closed-loop intelligent control. Display module: Uses an OLED screen to display temperature values, working status, working time, voltage parameters, etc. in real time for easy and intuitive monitoring; Power supply module: It adopts a miniaturized rechargeable lithium battery to provide stable, low-power, and long-term power supply for the entire system.

[0023] The device is a flexible, wearable, and lightweight structure that can be attached to the wound site on the limb to achieve continuous temperature monitoring, real-time intelligent response, closed-loop electrocatalytic therapy, and non-invasive wound care.

[0024] In practical applications, the temperature acquisition module and flexible electrodes can be integrated into the sensing / electrode system, while the voltage control module can be integrated into the data transmission / control system. These two parts can be connected via 3cm / 5cm / 7cm transmission lines. Specifically, the sensing / electrode system includes a temperature sensor and anode and cathode electrodes, enabling temperature sensing and voltage output for diabetic wounds. The data transmission / control system includes a microcontroller unit for data reception and processing, a rechargeable lithium-ion battery to provide a stable voltage to the sensing / electrode system, an OLED display screen to show the real-time temperature of the wound and the device's operating status (upper limit temperature, voltage, time), and a data output port to connect to a computer to manage the data collected by the flexible electronic device.

[0025] This application also provides applications of the above-mentioned devices for real-time temperature monitoring, electrocatalytic hydrogen production, anti-inflammatory, antibacterial, and healing-promoting care of wounds on the body surface, especially suitable for long-term home or clinical intelligent management of chronic, difficult-to-heal wounds such as diabetic foot ulcers, postoperative wounds, and pressure injuries.

[0026] Notably, this application innovatively utilizes the electrocatalytic properties of Pt@LS / PVA hydrogel for diabetic wound treatment. It leverages the material's ability to catalyze the production of hydrogen and active chlorine under voltage-driven conditions to regulate macrophage phenotype and kill bacteria. Similarly, it promotes cell proliferation and migration through electrical stimulation. Furthermore, this application designs a wearable flexible electronic device with wound temperature monitoring and voltage control, enabling accurate temperature detection and precise voltage control. By combining the flexible electronic device as a power source with the electrocatalytic properties of Pt@LS / PVA hydrogel, diabetic wound treatment can be achieved.

[0027] The following detailed description of the platinum-doped composite hydrogel, its preparation method, and wearable electronic device provided in this application is based on specific embodiments. However, the scope of protection of this application is not limited to the following embodiments. Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods; the materials and reagents used are commercially available unless otherwise specified.

[0028] Example 1: Preparation of Pt@LS / PVA hydrogel Preparation of LS / PVA hydrogels at different concentrations: 0.25 g of sodium lignosulfonate (LS) and 4.75 g of polyvinyl alcohol (PVA) were added to 45 mL of 0.01 M phosphate buffered saline (PBS). After stirring at room temperature for 1 h, the solution was heated and stirred in a 95 °C oil bath for 12 h until the PVA was completely dissolved. The mass fractions of the LS / PVA mixture were 0, 1, 3, 5, and 10 wt%. 1 mL of the completely dissolved LS / PVA solution was placed into a cubic silicone mold with a bottom area of ​​15 mm × 15 mm and cooled in a -20 °C refrigerator for 48 h. After being removed and allowed to return to room temperature, the LS / PVA hydrogels at different concentrations were obtained. Based on the different mass fractions of LS in the LS / PVA mixture, the hydrogels were named PVA, 1% LS / PVA, 3% LS / PVA, 5% LS / PVA, and 10% LS / PVA.

[0029] Preparation of different series of Pt@LS / PVA hydrogels: First, using a 10 wt% polyvinylpyrrolidone (PVP) solution prepared with PBS as the solvent, mixed solutions of potassium chloroplatinate (K2PtCl4) at different concentrations (0.01, 0.05, 0.1 M) and mixed solutions of ascorbic acid (VC) at different concentrations (0.005, 0.002, 0.1, 0.2 M) were prepared. Platinum was chemically reduced in situ within the prepared hydrogels using an impregnation method. Specifically, the prepared LS / PVA hydrogel (5% LS / PVA) was placed in a petri dish and immersed in K2PtCl4 / PVP solutions of different concentrations for 12 h, followed by washing once with deionized water. Then, VC solutions of different concentrations were added and the immersion continued for 12 h, followed by washing three times with deionized water. The resulting black hydrogel was the Pt@LS / PVA hydrogel. Unless otherwise specified, the preparation conditions of Pt@LS / PVA hydrogel are assumed to be 0.1 M for the K2PtCl4 mixed solution and 0.1 M for the VC mixed solution.

[0030] To explore the potential of hydrogels for use in diabetic wound dressings, the mechanical properties of LS / PVA hydrogels with different concentrations were studied. Figure 1 (a) shows the compressive stress-strain curves of the hydrogels. With increasing LS content, the compressive stress at 80% strain initially increases and then decreases. The 5% LS / PVA hydrogel exhibits the highest compressive stress, reaching 0.14 MPa at 80% strain, which is 1.75 times that of the pure PVA hydrogel (0.080 MPa). This is mainly due to the formation of hydrogen bonds between LS and PVA, thus improving the compressive properties of the hydrogel. The decrease in compressive stress of the 10% LS / PVA hydrogel may be due to excessive LS addition, which disrupts the uniformity of the hydrogel's cross-linking network, leading to a decrease in compressive properties. The mechanical properties of the hydrogels under tensile force are as follows: Figure 1 As shown in (b), a comparison of different tensile stress-strain curves reveals that the 5% LS / PVA hydrogel exhibits the highest elongation at break, reaching 418.87%, with a tensile strength of 0.023 MPa. In summary, the 5% LS / PVA hydrogel possesses the best mechanical properties; therefore, it was chosen as the experimental subject for subsequent research on Pt@LS / PVA hydrogels.

[0031] Furthermore, the Pt@LS / PVA hydrogel was characterized in various fundamental ways. First, the cross-sectional morphology of the LS / PVA hydrogel and the Pt@LS / PVA hydrogel was characterized using scanning electron microscopy (SEM). Figure 2(a) It can be observed that the LS / PVA hydrogel has a distinct porous structure with pore sizes ranging from approximately 1 to 6 μm. In contrast, the Pt@LS / PVA hydrogel synthesized via in-situ reduction exhibits significantly smaller pore sizes, generally distributed in the range of 0.1 to 1 μm. Meanwhile, from... Figure 2 As observed in (b), nanoparticles exist within the gel channels. These are likely particles formed by Pt loading onto the LS / PVA hydrogel, and this loading is not limited to the hydrogel surface; nanoparticles can also be observed within the internal channels. Because the in-situ reduction of Pt in the hydrogel is performed using an impregnation-reduction method, the resulting Pt particles exhibit heterogeneity. The stable loading of Pt in the LS / PVA hydrogel is primarily due to the complexing ability of LS for metal cations.

[0032] Furthermore, to further demonstrate the Pt loading, the crystal structure of the Pt@LS / PVA hydrogel was investigated using XRD. Figure 3 The XRD patterns of LS / PVA hydrogel, Pt@LS / PVA hydrogel, and platinum (JCPDS no. 87-0647) are shown. The figures show that Pt@LS / PVA hydrogel exhibits distinct diffraction peaks at 2θ = 40.2, 46.8, 68.3, 82.4, and 86.9°, corresponding to the (111), (200), (220), (311), and (222) crystal planes of platinum (JCPDS no. 87-0647), respectively. The diffraction peak of Pt@LS / PVA hydrogel at 2θ = 19.7° corresponds to the diffraction peak of pure LS / PVA hydrogel. This demonstrates the successful loading of Pt into LS / PVA hydrogel. The full XPS pattern and fine XPS pattern of Pt@LS / PVA hydrogel are shown below. Figure 4 As shown. Binding energies of other peaks were corrected using C 1s = 284.80 eV as the baseline. Comparison of the XPS full spectrum and fine spectrum reveals successful loading of Pt in the LS / PVA hydrogel. Furthermore, the predominant valence states of Pt in the Pt@LS / PVA hydrogel are 0 and +2, indicating that most of K2PtCl4 was successfully reduced to elemental platinum during hydrogel synthesis, which is beneficial for subsequent electrocatalytic reactions.

[0033] Furthermore, the electrical conductivity of the Pt@LS / PVA hydrogel was characterized, such as... Figure 5(a) shows the conductivity of Pt@LS / PVA hydrogels obtained by impregnation and reduction in K2PtCl4 solution and VC solution of different concentrations. Overall, the conductivity of the hydrogel increases with increasing K2PtCl4 concentration, while the conductivity tends to level off or even decrease when the VC concentration exceeds 0.2 M. This may be because increasing the K2PtCl4 concentration increases the platinum loading on the hydrogel surface, forming a good conductive network. However, the increased platinum loading may also cause blockage of the permeation channels, thus reducing the amount of VC solution permeating when the VC solution reaches its maximum, preventing further enhancement of the composite hydrogel's conductivity. Therefore, Pt@LS / PVA hydrogels obtained by impregnation and reduction in 0.1 M K2PtCl4 solution and 0.1 M VC solution will be used as the experimental subject for further research. Figure 5 As shown in (b), the conductivity of the Pt@LS / PVA hydrogel prepared under these conditions was verified by an LED light illumination experiment.

[0034] Furthermore, methylene blue (MB) was used as an oxidation probe for active hydrogen detection to investigate the electrocatalytic hydrogen production capability of Pt@LS / PVA hydrogel. The hydrogen detection mechanism of the MB probe is as follows: H2 reduces MB under the catalysis of Pt, leading to the decolorization of the blue MB solution. Figure 6 As shown, the decolorization reaction of MB was induced by electrocatalysis in LS / PVA hydrogel and Pt@LS / PVA hydrogel, and the generation of hydrogen in the Pt@LS / PVA hydrogel electrocatalytic system was investigated. Based on the relative change in the OD value of MB at 620 nm, it can be concluded that the hydrogen production by Pt@LS / PVA hydrogel electrocatalysis increases with time. The LS / PVA hydrogel group also underwent a certain reaction, which may be due to the swelling of the hydrogel after prolonged immersion in PBS, causing the platinum electrode clip to react with the salt solution in the LS / PVA hydrogel, thus leading to changes in the solution system. In addition, the storage time of the MB solution also affected its spectral characteristics.

[0035] 2,2-Aza-bis(3-ethyl-benzothiazole-6-sulfonic acid) diammonium salt (ABTS) was used as a probe to detect the active chlorine produced in the anodic reaction. Figure 7As shown in (a), the active chlorine produced by the electrocatalysis of Pt@LS / PVA hydrogel continuously increases with the extension of reaction time. The LS / PVA hydrogel group also exhibited a colorimetric reaction after 40 min, which may be due to the swelling of the hydrogel after prolonged immersion in PBS, causing the platinum electrode holder to react with the salt solution in the LS / PVA hydrogel, thus leading to changes in the solution system. Although the platinum electrode holder may have some errors under prolonged testing, the OD value of the Pt@LS / PVA hydrogel group at 405 nm is much larger than that of the LS / PVA hydrogel group, indicating that the Pt@LS / PVA hydrogel has the ability to produce active chlorine under electrocatalysis. Figure 7 (b) shows the color reaction caused by the accumulation of active chlorine under different voltages within the same time period. As the voltage increases, the active chlorine produced by the hydrogel electrocatalysis increases continuously, showing a positive correlation.

[0036] Considering the biosafety issues caused by chlorine and its future applications in biological systems, we will select 3V as the working voltage for the experiment (lower than the safe voltage for the human body) and 20 minutes as the working time for the experiment.

[0037] Furthermore, the ability of Pt@LS / PVA hydrogel to electrocatalyze and induce M2 macrophage polarization was investigated by testing the antigen expression of macrophages. Figure 8 As shown in (a), macrophages treated with interleukin-4 (IL-4) and lipopolysaccharide (LPS) exhibit typical M2 macrophage (CD86) characteristics. low CD206 high ) and M1 macrophages (CD86) high CD206 low The characteristics of M1 macrophages were observed. M1 macrophages pre-polarized with LPS were incubated with Pt@LS / PVA hydrogel or treated with LS / PVA hydrogel and Pt@LS / PVA hydrogel electrocatalysis. It was observed that the number of M1 macrophages in the group incubated only with Pt@LS / PVA hydrogel was increased compared to the negative control, with an M1 macrophage count of 19.55%. Under an electric field, the number of M2 macrophages increased in the LS / PVA+ES group and the Pt@LS / PVA+ES group, to 27.91% and 69.81%, respectively, while the number of M1 macrophages decreased to 6.25% and 0.31%, respectively. Figure 8(b) Quantitative statistics on macrophage phenotypes show that Pt@LS / PVA+ES has a strong ability to repolarize M2 macrophages. Specifically, the repolarization of M1 macrophages to M2 in the Pt@LS / PVA+ES group was mainly due to the combined effects of electrical stimulation and H2, while the repolarization of M2 macrophages in the LS / PVA+ES group was solely due to electrical stimulation. In conclusion, Pt@LS / PVA hydrogel electrocatalysis has a good ability to induce M2 macrophage polarization, indicating good anti-inflammatory properties.

[0038] Furthermore, the electrocatalytic antibacterial properties of Pt@LS / PVA hydrogel were investigated using methicillin-resistant Staphylococcus aureus (MRSA). Figure 9 As shown in (a), in the plate coating experiment, the bacterial count in the Pt@LS / PVA + ES group was significantly reduced, while the bacterial counts in both the Pt@LS / PVA group and the LS / PVA + ES group did not decrease significantly. Similarly, statistical analysis was performed on the survival rate of MRSA in the experiment, as shown in... Figure 9 As shown in (b), the data in the figure indicate that the Pt@LS / PVA + ES group exhibits the best antibacterial activity, 10 6 The survival rate of bacteria at a CFU / mL concentration decreased to below 10%, a statistically significant figure. This indicates that the electrocatalytic activity of the Pt@LS / PVA hydrogel has a bactericidal effect. Previous experiments have verified that the Pt@LS / PVA hydrogel can electrocatalyze the production of hydrogen and active chlorine under an electric field. Therefore, it is inferred that the excellent antibacterial performance of the Pt@LS / PVA + ES group mainly stems from the combined effect of hydrogen and active chlorine, where hydrogen can disrupt the bacterial membrane, thereby enhancing the bactericidal effect of active chlorine.

[0039] Furthermore, the ability of Pt@LS / PVA hydrogel to electrocatalyze cell proliferation and migration was verified using a NIH / 3T3 scratch assay. Figure 10 As shown, under electrical stimulation, the scratch healing rates of LS / PVA hydrogel and Pt@LS / PVA hydrogel were 54.0% and 57.4%, respectively, demonstrating considerable ability to promote cell proliferation and migration. This is mainly due to the enhanced cell signaling under the influence of the electric field, thereby promoting cell proliferation and migration. In addition, Pt@LS / PVA hydrogel itself also exhibits a certain ability to promote cell proliferation and migration, with a scratch healing rate of 45.1%. This may be because LS possesses certain biological activity, which is beneficial to cell growth.

[0040] The biocompatibility of wound dressings is a crucial indicator in medicine; therefore, the in vitro biocompatibility of Pt@LS / PVA hydrogel and its electrocatalytic therapy was evaluated using various methods. First, the biocompatibility of the hydrogel itself was tested using cytotoxicity assays, such as... Figure 11 As shown, both HUVEC and NIH / 3T3 normal cell lines maintained over 80% cell viability after co-culturing with 100% hydrogel extract for 24 h. Considering the biosafety of molecular hydrogen and reactive chlorine generated by electrical stimulation and electrocatalysis, the cytotoxicity of the Pt@LS / PVA hydrogel electrocatalytic process was tested. Figure 12 As shown in the cell viability and counterstaining experiments, neither the hydrogel nor the voltage-applied group caused significant damage to normal cells under a 3 V current voltage for 20 min. In conclusion, both the hydrogel itself and its electrocatalytic activity exhibit good biocompatibility.

[0041] Example 2: Design of a wearable flexible electronic device integrating continuous temperature monitoring and voltage regulation functions like Figure 13 As shown, the wearable flexible electronic device designed in this embodiment consists of two parts: a sensing / electrode system and a data transmission / control system. These two parts are assembled and connected using flexible transmission lines. The sensing / electrode system mainly consists of a temperature acquisition module (temperature sensor) and flexible electrodes (cathode / anode electrodes). The sensor's thermal pad has a diameter of 3.6mm and is used to sense the temperature of the wound site. The conductive areas of the anode and cathode electrodes are both 10mm × 10mm. The data transmission / control system includes: ① a 100mAh lithium-ion polymer battery with a reserved charging interface for power supply; ② a display screen for displaying the real-time temperature of the wound and the device's operating status (upper limit temperature, operating voltage, operating time); ③ a microcontroller unit (MCU) for data reading, logic processing, and outputting pulse-width modulation waves to provide the set voltage for the electrodes; ④ an antenna for wireless communication via Bluetooth Low Energy protocol; and ⑤ a data output port for connecting to a computer to manage the data collected by the flexible electronic device. All electronic components are integrated onto a 50mm × 37mm × 0.2mm flexible printed circuit board using hot-blow soldering with solder paste.

[0042] The flexible electronic device designed in this embodiment weighs only 7.02 g (sensing / electrode system: 0.47 g, data transmission / control system: 6.55 g). Figure 14As shown, the sensor / electrode system is about the thickness of an A4 sheet of paper, so it does not impose any weight burden on the human body when worn, and it does not affect normal human activities when worn on the subject's arm. Because the length of the transmission line can be customized, even if the sensor / electrode system is placed in areas that cannot be easily controlled (such as the soles of the feet or the back), it can still achieve data transmission / control system operation.

[0043] The system block diagram and control program execution flowchart of the flexible electronic device are as follows: Figure 15 As shown, the usage process is as follows: Turn on the power of the flexible electronic device, connect the device via Bluetooth using a mobile app, and set the device's start-up temperature, operating voltage, and operating time. After setting, temperature sensing begins. If the temperature exceeds the set upper limit temperature, the device will start working, outputting voltage for the set operating time, while the indicator light illuminates and the word "Working" is displayed on the OLED screen. When the temperature drops below the upper limit temperature or the set operating time is reached, the voltage automatically shuts off, the indicator light turns off, and the word "idle" is displayed on the OLED screen. Based on the condition exploration in the previous chapter and consideration of actual conditions, the upper limit temperature setting range of the designed flexible electronic device is 10~43℃, the output voltage range is 0~3V, and the single operating time range is 1~1200s.

[0044] In this study, the flexible electronic device was designed with a signal acquisition time interval of 1 second. To verify the sensitivity and accuracy of the flexible electronic device to temperature changes, a comparison was made between the temperature monitoring of the flexible electronic device and a thermal imager during the heating process. Figure 16 As shown in (a), flexible electronic devices can sensitively sense temperature changes with an accuracy comparable to that of thermal imagers. Therefore, their monitoring function can meet the needs of practical applications.

[0045] This flexible electronic device can monitor temperature in real time and switch its operating voltage by setting an upper temperature limit, thus enabling active treatment of inflamed wounds. A hairdryer was used to rapidly raise and lower the temperature to test the device's ability to control the voltage switch under rapid temperature changes. Since the local temperature of an inflamed wound will exceed 37℃, a temperature limit of 38℃ was set in the simulation experiment; that is, the operating voltage is activated when the temperature reaches 38℃ or higher, and deactivated when the temperature drops below 38℃. Figure 16 As shown in (b), by intermittently applying different temperatures, flexible electronic devices can quickly switch between voltage switches, exhibiting good dynamic feedback and stability.

[0046] To investigate the electrocatalytic ability of Pt@LS / PVA hydrogel to promote the healing of diabetic wounds, a mouse diabetic wound model was constructed. The procedure for treating diabetic wounds in mice using Pt@LS / PVA hydrogel electrocatalysis is as follows: Figure 17 As shown in the figure. The therapeutic effect of the Pt@LS / PVA hydrogel electrocatalytic system on diabetic wounds was evaluated by recording wound photographs of diabetic mice throughout the treatment process. Figure 18 Images (a) and (b) show the wound healing trajectory at different treatment stages and during treatment for each group, respectively. It is evident from the images that after 14 days, all wounds showed slow recovery; however, the Pt@LS / PVA+ES group exhibited the best wound healing effect. Furthermore, a temperature sensor continuously monitored the wound condition during treatment. Figure 18 (c) Statistical analysis was performed on the wound healing area, and the relative wound area obtained from the analysis is as follows: Figure 19 As shown in the figure, the average wound healing rate in the Pt@LS / PVA+ES group reached 82.32% after 14 days of treatment, while the average wound healing rate in the control group was only 56.50%. These results demonstrate that Pt@LS / PVA hydrogel electrocatalysis has the ability to promote wound healing in diabetic patients.

[0047] This embodiment performed histological analysis on regenerated skin at the wound site in mice to evaluate the wound healing process in diabetic mice. The results are as follows: Figure 20 As shown in the figure, H&E staining results indicated that after 14 days of treatment, the Pt@LS / PVA+ES group exhibited a relatively more intact epidermal layer. In contrast, the other three groups showed incomplete epithelial tissue. Collagen plays a crucial role in promoting angiogenesis and is essential for skin tissue regeneration. Masson staining was used to assess collagen deposition in wounds of diabetic mice in different treatment groups. Staining results showed that, compared with other groups, the Pt@LS / PVA+ES group had the greatest thickness of regenerated epidermis, with thicker, denser, and more uniformly arranged collagen fibers. Therefore, Pt@LS / PVA hydrogel electrocatalysis can promote epidermal tissue remodeling and collagen deposition, thereby accelerating wound healing in diabetic mice.

[0048] To evaluate the ability of Pt@LS / PVA hydrogel electrocatalysis to promote angiogenesis during wound repair, immunofluorescence staining analysis was performed on CD31 expression at diabetic wound sites in mice on day 14. The results are as follows: Figure 21 As shown in the immunofluorescence staining images, although all groups showed some CD31 protein expression, the CD31 expression in the Pt@LS / PVA+ES group was significantly higher than that in the other three groups. Therefore, compared with other groups, Pt@LS / PVA hydrogel electrocatalysis has a better ability to promote angiogenesis.

[0049] Immunofluorescence staining was used to characterize macrophages in mouse wounds on day 7 to demonstrate the in vivo anti-inflammatory effect of Pt@LS / PVA hydrogel electrocatalytic induction of M1 macrophages to M2 phenotype. Results are as follows: Figure 22 As shown in the figure, CD86 and CD206 are characteristic markers of M1 and M2 macrophages, respectively. Compared with other groups, the Pt@LS / PVA hydrogel + ES group showed significantly increased CD206 expression and significantly decreased CD86 expression in the wound. This demonstrates that the Pt@LS / PVA hydrogel electrocatalytic system has a strong ability to promote the transformation of macrophages into M2 type, thereby playing an anti-inflammatory role and facilitating the transformation of diabetic wounds from the inflammatory phase to the proliferative phase.

[0050] The biocompatibility of wound dressings in vivo is a crucial indicator for evaluating their practical application. If a wound dressing is toxic, it often leads to weight loss or even death in the organism. Therefore, the weight of mice was recorded regularly during wound treatment. Figure 23 As shown, during the Pt@LS / PVA hydrogel electrocatalytic treatment, the changes in body weight of mice in the experimental group were the same as those in the control group. The slight decrease in body weight in each group was mainly due to diabetes.

[0051] Histopathological analysis of major organs (heart, liver, spleen, lungs, and kidneys) in mice was performed using H&E staining. Figure 24 As shown, no significant pathological damage was observed in any of the groups. In conclusion, the application of Pt@LS / PVA hydrogel and electrocatalytic therapy in vivo also demonstrates good biocompatibility.

[0052] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for preparing a platinum-doped composite hydrogel, characterized in that, include: Sodium lignosulfonate and polyvinyl alcohol were dissolved in a phosphate buffer solution and subjected to one freeze-thaw cycle to obtain a sodium lignosulfonate / polyvinyl alcohol hydrogel; the total mass fraction of sodium lignosulfonate and polyvinyl alcohol was 3-10 wt%. Prepare a platinum source solution containing potassium chloroplatinate and a reducing solution containing ascorbic acid, controlling the concentration of potassium chloroplatinate to be 10~100mM and the concentration of ascorbic acid to be 5~200mM; The obtained sodium lignosulfonate / polyvinyl alcohol hydrogel was sequentially immersed in the platinum source solution and the reduction solution. Platinum nanoparticles were loaded inside the hydrogel through in-situ reduction. After washing, a platinum-doped composite hydrogel was obtained.

2. The method for preparing the platinum-doped composite hydrogel according to claim 1, characterized in that, The process of dissolving sodium lignosulfonate and polyvinyl alcohol in a phosphate buffer solution and subjecting the mixture to a single freeze-thaw cycle to obtain a sodium lignosulfonate / polyvinyl alcohol hydrogel comprises: Sodium lignosulfonate and polyvinyl alcohol were fully dissolved in a phosphate buffer solution in an oil bath at 90-95°C to form a homogeneous mixed solution. The mixed solution was subjected to freeze-thaw cycles at -20°C for 36-48 hours, and then restored to room temperature to obtain sodium lignosulfonate / polyvinyl alcohol hydrogel.

3. The method for preparing the platinum-doped composite hydrogel according to claim 1, characterized in that, The preparation of the platinum source solution containing potassium chloroplatinate and the reducing solution containing ascorbic acid includes: A polyvinylpyrrolidone solution was prepared using phosphate buffer solution as a solvent. A platinum source solution containing potassium chloroplatinate and a reducing solution containing ascorbic acid were prepared, with the concentrations of potassium chloroplatinate and ascorbic acid controlled at 100 mM.

4. The method for preparing the platinum-doped composite hydrogel according to claim 1, characterized in that, The total mass fraction of sodium lignosulfonate and polyvinyl alcohol is 5 wt%.

5. A platinum-doped composite hydrogel, characterized in that, It is prepared by the preparation method according to any one of claims 1-4.

6. The application of the platinum-doped composite hydrogel of claim 5 in the preparation of electrically driven wound care materials, characterized in that, The platinum-doped composite hydrogel generates active hydrogen and active chlorine through electrocatalysis under external voltage, thereby achieving anti-inflammatory and antibacterial effects on wounds and promoting wound healing.

7. A wearable electronic device, characterized in that, It includes a temperature acquisition module, a flexible electrode, and a voltage control module electrically connected to both the temperature acquisition module and the flexible electrode; wherein, The temperature acquisition module is used to acquire the temperature signal of the wound site in real time; The flexible electrode is a hydrogel electrode formed using the platinum-doped composite hydrogel of claim 5. The hydrogel electrode can generate active hydrogen and active chlorine in situ under voltage drive, thereby achieving anti-inflammatory, antibacterial and wound healing functions. The voltage control module is used to determine whether to activate the electrocatalytic treatment of the flexible electrode based on the temperature signal.

8. The wearable electronic device according to claim 7, characterized in that, The voltage control module is configured such that when the wound temperature collected by the temperature acquisition module exceeds a preset threshold, it automatically outputs a preset voltage to power the flexible electrode, driving the electrode to electrocatalyze the generation of hydrogen and active chlorine within a preset time; when the wound temperature returns to a normal level, it automatically shuts off the output voltage, enabling the device to achieve continuous temperature monitoring, real-time intelligent response, and closed-loop feedback.

9. The wearable electronic device according to claim 8, characterized in that, The wearable electrocatalytic therapy device also includes a display module for displaying temperature data and device operating status in real time.

10. The application of a wearable electronic device according to any one of claims 7-9 in wound care, temperature monitoring and electrocatalytic hydrogen production.

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