Preparation And Performance Study Of Copper-based MOF Functionalized Hydrogel

Traditional chitosan-based hydrogels are widely used as medical wound dressings due to their high water absorption,biocompatibility,biodegradability,non-cytotoxicity and non-antigenicity.The chronic wound site will produce high concentrations of reactive oxygen species?ROS?such as H₂O₂ by-products and pro-inflammatory mediators.Too much ROS production will cause oxidative stress,resulting in impaired function of ski n fibroblasts and keratinocytes;chronic wound wounds A large amount of exudate is e asily infected by pathogenic microorganisms,causing physiologic disorders of human ti ssues.Obviously,traditional chitosan-based hydrogels cannot cope with such challenges.In this paper,good antibacterial,antioxidant and mechanical properties are given to chitosan hydrogel,and copper-based MOF functional hydrogel is prepared,which is used as a medical dressing to promote wound healing.First,glutathione?reduced form??GSH?was grafted onto the carboxymethyl chitosan?CMCS?molecular chain?CMCS-GSH?to give it antioxidant properties;then it was combined with acrylamide?AA?and The cross-linking agent forms a hydrogel through free radical polymerization,which has good mechanical properties and oxidation resistance;finally,copper ions are loaded into the hydrogel in the form of copper-based MOF?HKUST-1?to prepare the copper-based MOF function Hydrogel,and a series of characterization.Specific research content:?1?glutathione?reduced form??GSH?was grafted onto the carboxymethyl chitosan?CMCS?molecular chain to prepare the antioxidant CMCS-GSH,and then the CMCS-GSH/AA and The coupling agent prepares chitosan-based antioxidant hydrogel with good mechanical properties through free radical polymerization.Using its in vitro scavenging free radicals,it is shown that as the grafting rate of GSH increases,the oxidation resistance of chitosan-based antioxidant hydrogels improves;the mechanical properties of CMCS-GSH/AA with different mass ratios on hydrogels are tested by rheology Impact;use SEM,swelling rate,water retention rate and cell proliferation to evaluate the ability of hydrogels as substrates for medical dressings.?2?Evaluate the solution method to prepare copper-based MOF?HKUST-1?nanoparticles with non-uniform sizes,and then load it into the hydrogel as an antibacterial agent to prepare copper-based MOF functionalized hydrogel.In vitro antibacterial characterization of different concentrations of HKUST-1 against Staphylococcus aureus?S.aureus?and E.coli?E.coli?,when the concentration is greater than 3.12?g/m L,HKUST-1 against S.aureus and E The inhibition rate of coli is close to 100%,which indicates that HKUST-1 is an excellent antibacterial agent;SEM,swelling rate,water retention rate and rheology are used to characterize the effect of HKUST-1 on the hydrogel performance.?3?Prove its feasibility as a medical dressing by characterizing the in vitro drug release,in vitro antioxidant properties,in vitro antibacterial properties,cytotoxicity and wound healing of copper-based MOF functionalized hydrogels.The results show that copper ions loaded into the hydrogel in the form of copper-based MOF?HKUST-1?can slowly release copper ions,and the drug release period reaches more than 48h;when the concentration of HKUST-1 in the hydrogel is 500?g/m L,it exceeds 80% of Staphylococcus aureus and E.coli were killed;when the concentration of HKUST-1 in the hydrogel was 1000?g/m L,almost 100% of Staphylococcus aureus and E.coli were killed;copper-based MOF functionalized hydrogel Wound healing was significantly accelerated,and the wound basically healed at 7days.