Preparation method and application of chitosan-based hydrogel wound dressing
By preparing a chitosan-based hydrogel wound dressing, and combining the cross-linking of thiol chitosan, carbon nanotubes, and protocatechuic aldehyde, the problems of insufficient mechanical properties, antibacterial properties, and monitoring capabilities of traditional hydrogel dressings are solved, realizing multifunctional wound management and personalized treatment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-11
- Publication Date
- 2026-04-10
AI Technical Summary
Existing hydrogel dressings are insufficient in terms of mechanical properties, active antibacterial ability, tissue adhesion, and on-demand detachment ability, making it impossible to achieve real-time monitoring of wound condition and on-demand treatment, and thus failing to meet the needs of modern precision medicine.
A method for preparing chitosan-based hydrogel wound dressings involves dissolving chitosan in acetic acid solution, adding cysteine, dialyzing and freeze-drying to form thiol chitosan, and then crosslinking it with carbon nanotubes and protocatechuic aldehyde to form a hydrogel with oxidative polymerization capabilities, integrating motion sensing functions.
The mechanical properties and conductivity of the hydrogel have been improved, enabling active antibacterial action and real-time monitoring of infected wounds. It also has the ability to detach on demand, making it suitable for the healing of complex wounds and personalized care.
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Abstract
Description
Technical Field
[0001] This invention relates to the technical fields of wound dressings and flexible sensing, and particularly to a method for preparing a chitosan-based hydrogel wound dressing and its application. Background Technology
[0002] With the improvement of people's living standards and the enhancement of medical and health awareness, the treatment and management of chronic wounds, postoperative wounds, and infected wounds have become key and challenging aspects of clinical nursing. Traditional wound dressings, such as gauze and cotton pads, have limited functions, only providing coverage and isolation. They are not only ineffective in meeting the healing needs of complex wounds but also prone to adhering to newly formed tissue, leading to secondary damage during dressing changes. Therefore, there is an urgent need to develop intelligent wound dressings with multiple repair functions to promote wound healing and alleviate patient suffering. Hydrogels, due to their three-dimensional network structure, high water content, good biocompatibility, and properties similar to the natural extracellular matrix, show great application potential in the field of wound dressings. They can provide a moist healing environment for the wound, absorb exudate, and allow oxygen exchange. However, most traditional hydrogel dressings are prepared through chemical cross-linking, often resulting in poor mechanical properties and difficulty in adhering to moving parts such as joints. Furthermore, they lack active antibacterial capabilities and cannot cope with infections caused by drug-resistant bacteria. In addition, traditional dressings often cannot be removed without damage in the later stages of wound healing, easily damaging newly formed granulation tissue. More importantly, most hydrogel dressings have a single function, serving only as passive coverings. They cannot achieve real-time monitoring of wound condition, nor can they provide on-demand treatment based on the healing process. Therefore, an ideal hydrogel wound dressing should integrate excellent mechanical adaptability, active antibacterial ability, anti-inflammatory and antioxidant properties, reliable tissue adhesion, and on-demand detachment capability. It should even possess electrical signal conduction capabilities to achieve wound monitoring, thereby meeting the urgent needs of modern precision medicine and personalized care. Summary of the Invention
[0003] In view of the above-mentioned problems in the prior art, the present invention provides a method for preparing a chitosan-based hydrogel wound dressing that integrates multiple functions such as self-healing, adhesion, antibacterial properties and motion sensing, and its application.
[0004] To achieve the above objectives, the technical solution adopted in this paper is as follows: a method for preparing a chitosan-based hydrogel wound dressing, comprising the following steps:
[0005] (1) Dissolve chitosan in acetic acid solution to obtain a transparent chitosan solution;
[0006] (2) Cysteine was added to the chitosan solution in step (1) and the mixture was magnetically stirred. The resulting mixture was dialyzed with deionized water and then freeze-dried to obtain thiol chitosan;
[0007] (3) After dissolving the thiol chitosan obtained in step (2), carbon nanotubes and protocatechuic aldehyde are added, and hydrogel wound dressing is obtained through oxidative polymerization crosslinking.
[0008] As a preferred embodiment, the chitosan solution in step (1) has a mass concentration of 1 wt%.
[0009] As a preferred embodiment, the molar ratio of cysteine to N-acetyl-D-glucosamine units of chitosan in step (2) is 1:(1~5). More preferably, the molar ratio of cysteine to N-acetyl-D-glucosamine units of chitosan in step (2) is 1:1.
[0010] As a preferred option, the reaction temperature in step (2) is 28 °C.
[0011] As a preferred embodiment, the mass concentration of the thiol chitosan solution in step (3) is 1~3 wt%. More preferably, the mass concentration of the thiol chitosan solution in step (3) is 2 wt%.
[0012] As a preferred embodiment, the amount of carbon nanotubes in step (3) is 0 to 1 mg. More preferably, the amount of carbon nanotubes in step (3) is 0.4 mg.
[0013] As a preferred option, the amount of protocatechuic aldehyde in step (3) is 1 mg.
[0014] This invention provides the application of the above-mentioned hydrogel wound dressing in wound healing and motion sensing.
[0015] Compared with the prior art, the present invention has the following beneficial effects: the wound dressing prepared by the CSPC hydrogel of the present invention has great potential in the treatment of infected wounds and real-time health monitoring, and provides a new design idea for the construction of an intelligent integrated wound management system. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.
[0017] Appendix Figure 1 The figures show the rheological test results of the hydrogel wound dressings prepared in Examples 1, 2, 3, and 4, respectively. CSPC is labeled as Example 1 and CSPC. 0.04 Example 2, CSPC 0.4 Example 3, CSPC 1.0 Example 4.
[0018] Appendix Figure 2The images show the photothermal results of the hydrogel wound dressings prepared in Examples 1, 2, 3, and 4, respectively.
[0019] Appendix Figure 3 The graph shows the conductivity test results of the hydrogel wound dressings prepared in Examples 1-4.
[0020] Appendix Figure 4 The image shows the antibacterial results of the hydrogel wound dressing prepared in Example 3.
[0021] Appendix Figure 5 The figures show the experimental results of the sensing performance of the hydrogel wound dressing prepared in Example 3. Among them, (a) is the test result of the sensitivity factor (GF) of the hydrogel strain sensor, and (b) is the graph of the relative resistance change of the hydrogel strain sensor when monitoring the bending of a human finger. Detailed Implementation
[0022] (1) Dissolve chitosan in acetic acid solution to obtain a transparent chitosan solution;
[0023] (2) Cysteine was added to the chitosan solution in step (1) and the mixture was magnetically stirred. The resulting mixture was dialyzed with deionized water and then freeze-dried to obtain thiol chitosan;
[0024] (3) After dissolving the thiol chitosan obtained in step (2), carbon nanotubes and protocatechuic aldehyde are added, and hydrogel wound dressing is obtained through oxidative polymerization crosslinking.
[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.
[0026] Example 1
[0027] A method for preparing a chitosan-based hydrogel wound dressing includes the following steps:
[0028] (1) Dissolve chitosan in acetic acid solution to obtain a transparent chitosan solution;
[0029] (2) Cysteine was added to the chitosan solution in step (1) and the mixture was magnetically stirred. The resulting mixture was dialyzed with deionized water and then freeze-dried to obtain thiol chitosan;
[0030] (3) After dissolving the thiol chitosan obtained in step (2), carbon nanotubes and protocatechuic aldehyde are added, and a hydrogel wound dressing is obtained through oxidative polymerization crosslinking. The amount of carbon nanotubes is 0 mg, and the amount of protocatechuic aldehyde is 1.0 mg.
[0031] Example 2
[0032] A method for preparing a chitosan-based hydrogel wound dressing includes the following steps:
[0033] (1) Dissolve chitosan in acetic acid solution to obtain a transparent chitosan solution;
[0034] (2) Cysteine was added to the chitosan solution in step (1) and the mixture was magnetically stirred. The resulting mixture was dialyzed with deionized water and then freeze-dried to obtain thiol chitosan;
[0035] (3) After dissolving the thiol chitosan obtained in step (2), carbon nanotubes and protocatechuic aldehyde are added, and a hydrogel wound dressing is obtained through oxidative polymerization crosslinking. The amount of carbon nanotubes is 0.04 mg, and the amount of protocatechuic aldehyde is 1.0 mg.
[0036] Example 3
[0037] A method for preparing a chitosan-based hydrogel wound dressing includes the following steps:
[0038] (1) Dissolve chitosan in acetic acid solution to obtain a transparent chitosan solution;
[0039] (2) Cysteine was added to the chitosan solution in step (1) and the mixture was magnetically stirred. The resulting mixture was dialyzed with deionized water and then freeze-dried to obtain thiol chitosan;
[0040] (3) After dissolving the thiol chitosan obtained in step (2), carbon nanotubes and protocatechuic aldehyde are added, and a hydrogel wound dressing is obtained through oxidative polymerization crosslinking. The amount of carbon nanotubes is 0.4 mg, and the amount of protocatechuic aldehyde is 1.0 mg.
[0041] Example 4
[0042] A method for preparing a chitosan-based hydrogel wound dressing includes the following steps:
[0043] (1) Dissolve chitosan in acetic acid solution to obtain a transparent chitosan solution;
[0044] (2) Cysteine was added to the chitosan solution in step (1) and the mixture was magnetically stirred. The resulting mixture was dialyzed with deionized water and then freeze-dried to obtain thiol chitosan;
[0045] (3) After dissolving the thiol chitosan obtained in step (2), carbon nanotubes and protocatechuic aldehyde are added, and a hydrogel wound dressing is obtained through oxidative polymerization crosslinking. The amount of carbon nanotubes is 1.0 mg, and the amount of protocatechuic aldehyde is 1.0 mg.
[0046] Note: In "CSPC" X In the Chinese text: CS represents thiol chitosan, P represents protocatechuic aldehyde, C represents carbon nanotubes, and "x" represents the mass of carbon nanotubes.
[0047] The hydrogel materials prepared in Examples 1-4 were tested for their rheological properties (γ = 1-1000%) using a rheometer. The test results for Examples 1-4 are attached. Figure 1 As shown in the figure. The results demonstrate that suitable carbon nanotubes are beneficial for improving the modulus of hydrogels and enhancing their mechanical properties.
[0048] The heating curves of the hydrogel materials prepared in Examples 1-4 were recorded under 808 nm laser irradiation. The test results for Examples 1-4 are attached. Figure 2 As shown in the figure. The results demonstrate that increasing the amount of carbon nanotubes added is beneficial for increasing the photothermal temperature of the hydrogel.
[0049] The conductivity of the hydrogel materials prepared in Examples 1-4 was measured using a CHI660E electrochemical workstation, and the calculation formula is as follows:
[0050] σ = L / (R×S) (1)
[0051] Where L is the height of the hydrogel, S is the cross-sectional area, and R is the measured resistance of the hydrogel.
[0052] The test results are attached. Figure 3 As shown, the electrical conductivity of Examples 1-4 is S / m, respectively. The hydrogel wound dressing prepared in Example 3 has the best mechanical properties and electrical conductivity; therefore, the hydrogel prepared in Example 3 was selected for subsequent testing.
[0053] The antibacterial properties of the hydrogel wound dressing prepared in Example 3 were tested. *Escherichia coli* (E. coli) was used as a representative of Gram-negative bacteria, *Staphylococcus aureus* (S. aureus) as a representative of Gram-positive bacteria, and PBS-treated bacterial suspension was used as a control group. Their antibacterial properties were evaluated using the spread plate method. The results are attached. Figure 4 As shown, the hydrogel wound dressing prepared in Example 3 exhibits excellent antibacterial properties against both E. coli and S. aureus, enabling it to be used to treat bacterially infected wounds.
[0054] The change in relative resistance of the hydrogel prepared in Example 3 during the stretching process was measured using a CHI660E electrochemical workstation, and its sensitivity factor (GF) was calculated using the following formula:
[0055] GF = (ΔR / R0) / ε (2)
[0056] Where ΔR is the change in hydrogel resistance during stretching, R0 is the initial resistance of the hydrogel before stretching, ΔR / R0 is the relative resistance of the hydrogel during stretching, and ε is the corresponding strain value of the hydrogel during stretching.
[0057] As attached Figure 5 As shown in Figure a, the strain sensor prepared based on the hydrogel of Example 3 has a GF value of 0.2 within a strain range of 0-20%, demonstrating its ability to provide a sensitive electrical signal response over a relatively wide strain range. The hydrogel wound dressing prepared in Example 3 was adhered to the knuckle as a strain sensor material to verify the feasibility of flexible strain sensing (see attached figure). Figure 5 (b) It can be observed that as the finger bends back and forth, the strain sensor generates a stable and repeatable electrical signal feedback, demonstrating that the hydrogel wound dressing has good repeatability, stability, and sensitivity, and is fully suitable for use as a sensing material.
[0058] The above description is merely a preferred embodiment of the present invention, and should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.
Claims
1. A method for preparing a chitosan-based hydrogel wound dressing, characterized in that, Includes the following steps: (1) Dissolve chitosan in acetic acid solution to obtain a transparent chitosan solution; (2) Cysteine was added to the chitosan solution in step (1) and the mixture was magnetically stirred. The resulting mixture was dialyzed with deionized water and then freeze-dried to obtain thiol chitosan; (3) After dissolving the thiol chitosan obtained in step (2), carbon nanotubes and protocatechuic aldehyde are added, and CSPC hydrogel is obtained through oxidative polymerization.
2. The method for preparing the hydrogel wound dressing according to claim 1, characterized in that, In step (1), the concentration of the chitosan solution is 1~3 wt%.
3. The method for preparing the hydrogel wound dressing according to claim 1, characterized in that, In step (2), the molar ratio of cysteine to the N-acetyl-D-glucosamine unit of chitosan is 1:(1~5).
4. The method for preparing the hydrogel wound dressing according to claim 1, characterized in that, The reaction temperature described in step (2) is 20~30 ℃.
5. The method for preparing the hydrogel wound dressing according to claim 1, characterized in that, The deionized water dialysis time mentioned in step (2) is at least 5 days.
6. The method for preparing the hydrogel wound dressing according to claim 1, characterized in that, The mass concentration of the thiol chitosan solution mentioned in step (3) is 1~3 wt%.
7. The method for preparing the hydrogel wound dressing according to claim 1, characterized in that, The mass of the carbon nanotubes mentioned in step (3) is 0~1.0 mg, and the mass of protocatechuic aldehyde is 1.0~5.0 mg.
8. A hydrogel wound dressing obtained by the preparation method according to any one of claims 1-7.