Preparation And Properties Of Multi-responsive Tunicate Cellulose Nanocrystals Strengthened Supramolecular Hydrogels For Wound Dressings

The skin is vulnerable to damage and often takes a long time to repair before it can restore its normal physiological functions.In general,the microenvironment of injured skin is at high temperature and acidic.As temporary replacement for the skin,an ideal wound dressing should adapt to physical environment around wound site,which can be beneficial to promote tissue growth and wound healing and reduce scar formation.Multi-responsive supramolecular hydrogels can provide new material properties that hydrogels based on traditional principles lack,and can realize reversible and dynamic control of hydrogel structure.The pH and temperature responsive hydrogel dressings can realize the in-situ release of drugs in a slow and controlled way,which can meet the demands of wound repair.In addition,light can control the molecular structure of hydrogels containing photo-sensitive molecules remotely and efficiently.However,hydrogel wound dressings that have been reported have the problems of insufficient intelligent response and low mechanical strength.In this study,an injectable polydopamine-coated tunicate nanocellulose strengthened supramolecular hydrogel was designed.The specific content and results of this research could be divided into the following two parts:1.Tunicate nanocellulose nanocrystals(TCNCs)and polydopamine coated tunicate cellulose nanocrystals(PDA@TCNCs)were prepared from Halocynthia roretzi.Chitosan was chemically modified and coupled with quaternary ammonium groups to synthesize quaternary ammonium chitosan(QCS),based on that,α-cyclodextrin was grafted on QCS to prepare quaternary ammonium chitosan grafted α-cyclodextrin(QCS-α-CD).Attaching azo phenyl groups to the ends of Pluronic F127,phenylazo-terminated Pluronic F127(F127AZO)was synthesized by esterification reaction,and its drug-loaded micelles(Cur-F127AZO)were also prepared with F127AZO.Under physiological conditions,QCS-α-CD as a host,F127AZO as a guest and PDA(@TCNCs as a strengthening filler,hydrogel was prepared by host-guest interaction.Schiff base bond and multiple hydrogen bond.The precursors and hydrogel were characterized by 1H-NMR,FTIR,XRD,TGA,DLS.2.The performance test of the hydrogel as a wound dressing was studied.By studying intelligent responses,self-healing ability,antibacterial property,adhesive performance,degradable tests,drug release behavior,hemostatic performance,biocompatibility,ability of accelerating wound healing,the applicability of the hydrogel as a wound dressing was explored.This novel multiple-responsive supramolecular hydrogel can provide a new idea for clinical treatment to promote wound healing.