Design Of Multifunctional Hydrogel And Its Application In Wound Dressing

Skin injury is one of the most common surgical injury for human even mammal.Accelerating wound healing and improving healing effect are the long-term goals of human beings.At present,the wound dressings industry is facing multiple challenges,such as the innovation of treatment concept and the acceleration of product iteration.Wound dressings based on the theory of wet healing are gradually replacing the traditional dry dressings.There is a growing tendency for dressings to be diversified,bionic and customized.However,the current wound dressings are still far from being ideal wound dressings due to many problems,such as the mismatch between mechanical properties and wound surface,insufficient antibacterial time,poor air permeability,and easy to cause secondary infection.In terms of basic research and clinical application,it is of great practical significance to study the innovative engineering application of wound dressings.This study focuses on the development of a hydrogel wound dressing that can accelerate wound healing and care patients’ experience with the method of engineering research.The work is summarized as follows:(1)Develop functional hydrogels according to the actual use scenarios of wound dressings.Current hydrogel wound dressings have poor anti-dehydration performance,which seriously limits the clinical application of hydrogel.In this part,polyvinyl alcohol(PVA)is used as the substrate of hydrogels,and the single water solvent system is changed into glycerol-water(GW)binary solvent system,which makes hydrogels have good anti-dehydration performance and greatly prolongs the practical service life.The presence of glycerol gave the hydrogels a wide temperature window,which enabled the hydrogels to maintain stability at extreme temperatures(-20 ℃and 60 ℃).This section uses casein(CEs)as an adhesive component to provide adhesion.It was observed that both glycerol and casein could significantly improve the mechanical properties of PVA hydrogels.The obtained CEs/PVA GW hydrogels were characterized by water content,swelling rate(SR),water retention rate,electron microscopy,infrared(FTIR),X-ray diffraction(XRD),etc.The mechanical properties,adhesion properties,frost resistance and high temperature resistance of hydrogels were tested.CES/PVA GW hydrogel has good mechanical properties,adhesion properties,dehydration resistance,frost resistance/high temperature resistance properties,has basically met the basic characteristics of wound hydrogel materials,and can meet the actual use requirements of wound dressing.(2)CEs/PVA GW hydrogel existing function optimization strategy and in-depth function development.The movement frequency and displacement range of the wound in different parts are obviously different,so the wound dressing must establish effective mechanical compatibility with the wound.By adjusting the ratio of raw materials,hydrogels and hydrogels synthesis formulas with different mechanical properties can be obtained,which can guide the preparation of wound dressing.By adjusting the amount of casein,hydrogels with different adhesion properties and the synthesis formula of adhesion properties can be obtained.The ratio of glycerol significantly affects the performance of hydrogels and the ability of resist water loss at extreme temperatures.In addition,the unique self-assembled micelle structure of casein has been developed as a drug-carrying micelle.Allicin was loaded into casein micelles by casein suspension and then embedded into hydrogel matrix to form a dual sustained-release system,the release behavior was still observed after 140 hours at room temperature.The release of allicin can maintain its antibacterial properties,and has a good and long-term killing effect on Escherichia coli and Staphylococcus aureus.The integrated design of CEs/PVA GW lotion hydrogel has excellent long-term antimicrobial properties and sustained drug release properties,further increasing the possibility of practical application as a wound dressing.(3)Study on the application of multifunctional hydrogel to wound dressing.It can be divided into the state test of hydrogel wound dressing in clinical use and the engineering design in large-scale production.The state tests in clinical use mainly include tensile tests under multiple loading and unloading,strain tests,effective adhesion formation time,relationship between adhesion force and usage times,permeability tests,drug slow release behavior under complex conditions,bacterial killing rate,effective bacteriostatic time,cell proliferation and toxicity tests.According to the test results,the mechanism of promoting healing of hydrogel wound dressing was further studied comprehensively.The engineering design in large-scale production includes the technological process of mass production of hydrogel wound dressing and the product design of wound dressing.Large-scale production can be realized through simple technological process,and a pressure sensitive adhesive-hydrogel wound dressing with a three-layer sandwich structure of non-woven fabric was designed,which further increases the possibility of hydrogel wound dressings being marketed as products.The application research of this part has obvious guiding significance for the design and test of hydrogel wound dressing.