Structure Design And Properties Research Of Hydrogel Dressing

Hydrogel,as a material similar to human skin tissue,has attracted extensive attention from researchers.Among them,hydrogel as medical dressing and drug delivery is the focus of research.However,as a medical dressing,hydrogels usually have many disadvantages such as weak mechanical properties,poor water retention and inability to control drug release precisely,so it cannot meet the requirement of practical application.It is still a challenging problem to prepare hydrogels equipped with good mechanical strength,strong water retention and the ability to control drug release.Therefore,it is of great significance to prepare a hydrogel medical dressing that meets these above requirements.First,in this work,a composite bilayer(DL)hydrogel containing drug release layer(DRL)and mechanical support layer(MSL)was prepared using polyvinyl alcohol(PVA)and sodium carboxymethyl cellulose(CMC)as raw materials.DRL can achieve slow drug release by adding β-cyclodextrin polymer(β-CDP)as the drug carrier,while MSL can improve the mechanical strength and water retention of the hydrogel by immersing salt solution.Then,diclofenac sodium(DS)was introduced into DRL as a model drug to explore its unique drug release model of the DL hydrogel and explain its mechanism.The results showed that the drug release curve of DL hydrogel conforms to diffused-relaxation-corrosion model.The mechanical strength,drug release behavior and water retention performance of the bionic DL hydrogel were investigated by multiple characterization methods.It was proved that the bionic DL hydrogel could retain water and provided sufficient mechanical strength while maintaining the drug slow release,which indicated the hydrogel had good potential as a hydrogel dressing.Next,by preparing self-assembled drug-loading micelles and post-foam salt solutions,this work developed a tough,anti-swelling,anti-water loss and mechanically-responsive Methoxypolyethylene glycol amine-D-α-Tocopherol Succinate@Curcumin(mPEGTOS@Cur)micelle hydrogel that delivers drugs in a mechanically-responsive manner,aiming to solve the problem of controlling drug release through readily available external mechanical stimuli.As macromolecular crosslinking agents and drug carriers,mPEGTOS@Cur micelles would deform under mechanical stress,resulting drug release.In addition,the hydrogel has good mechanical strength,water loss resistance and swelling resistance by the combined action of magnesium sulfate and drug loading micelles after soaking salt solution.Then,we investigated the antibacterial ability of the hydrogel against gram-positive bacteria and gram-negative bacteria,and found that the hydrogel has certain antibacterial effect on escherichia coli and Staphylococcus aureus.This mechanical responsive hydrogel dressing has a wide application prospect in wound treatment due to its good anti-swelling,water retention,controllable drug release ability and certain antibacterial effect.To sum up,we designed two kinds of drug loaded hydrogel dressings to overcome the defects of traditional hydrogel dressings in mechanical strength,water retention and controlled release of drugs,and expand the practical application range of medical dressings and field of wound care.