Preparation And Applications Of Adhesive Antibacterial Hydrogels

Microbial infection is one of the most common complications in clinical medicine.Antibacterial materials can effectively kill bacteria and resist microbial infection.However,traditional antibacterial materials have the defects of poor air permeability and poor compliance with wound surface.In recent years,hydrogels are widely used in biosensors,wound dressings,tissue adhesive and other biomedical fields because of their excellent flexibility and biocompatibility.Therefore,the research of antibacterial hydrogels is of great significance in the biomedical field.In this thesis,two kinds of adhesive antibacterial hydrogels were prepared and their potential application in wound dressing was studied.The main research contents and results are as follows:1.A bioinspired antibacterial tissue adhesive hydrogel wound dressing was synthesized by methacryloylamido adenine(MA-Ade) and 3-Dimethyl(methacryloyloxyethyl)ammonium propanesulfonate(DMAPS).Then,chitosan was introduced in the hydrogel as a second network to obtain PDM/C hydrogel.Structure of PDM/C hydrogel was characterized by fourier transform infrared spectroscopy(FT-IR)and its thermo property was determined by differential scanning calorimeter(DSC).Scanning electron microscopy(SEM)was used to observe the surface morphology of the lyophilized hydrogel.The mechanical properties of the hydrogel were studied by rheometer.Moisture retention of the hydrogel was investigated by water vapor transmittance experiment.The adhesion of the hydrogel to pork rind was characterized by lap shear experiments.Staphylococcus aureus(S.aureus)and Escherichia coli(E.coli)were selected as representative bacterial for bacterial cell attachment assay and antibacterial test in vitro.Finally,the wound healing characteristic of PDM/C hydrogel was evaluated in a mouse model.All results demonstrated that the PDM/C hydrogel may be as a highly promising therapeutic for wounds healing and skin regeneration because of its good mechanical properties,moisturizing properties,adhesion and antibacterial properties.2.A highly adhesive antibacterial hydrogel(GW-Gel)was prepared by copolymerization of DMAPS and MA-Ade with water-glycerin as solvent and poly(hexamethylene guanidine)derivative with two terminal methacrylates(PHMGDMA)as a crosslinker.Swelling ratio of the hydrogels was determined by the weighing method.The moisture retention,frost resistance and adhesion were also investigated.The effects of MA-Ade content,PHMGDMA content and glycerol content on mechanical properties of the hydrogels were investigated by universal tester.The elasticity of the GW-Gel hydrogels was determined by compressive stress-strain curve.Staphylococcus aureus(S.aureus)and Escherichia coli(E.coli)were selected as representative bacteria for antibacterial test in vitro.The results showed that GW-Gel hydrogel could adhere to different substrates tightly and effectively inhibit bacterial proliferation.