Antimicrobial and antifouling nanocomposite hydrogels containing polythioether dendron: high-loading silver nanoparticles and controlled particle release

A series of nanocomposite (NC) hydrogels containing dendritic polythioether segments were successfully prepared by free radical copolymerization. Due to the multiple thioether functional groups and the strong chelating ability of the thioether groups with metal elements, these hydrogels showed excellent absorption towards Ag nanoparticles. The size of the Ag nanoparticles (AgNPs) embedded in the hydrogel matrix can be regulated by tuning the content of dendritic segments in the polymer matrix. Small-sized AgNPs were formed with increasing of the content of polythioether dendrons. Besides, the Ag release kinetics was investigated. The hydrogels containing dendrons showed higher AgNPs loading and displayed enhanced retention of nanoparticles as compared with the pristine poly-N-isopropyl acrylamide (PNIPAM) hydrogel. Furthermore, these NC hydrogels, especially those containing dendritic segments, showed much better antimicrobial performance for Escherichia coli and anti-algae performance. These NC hydrogels have promising applications in marine antifouling coating and interfaces of biomaterials.