Fast and long-acting antibacterial properties of chitosan-Ag/polyvinylpyrrolidone nanocomposite films

► CHI-Ag/PVP nanocomposite film prepared can release Ag+ at a controlled rate. ► Pretreatment of substrate enhanced the binding capacity of films in PBS buffer. ► Increasing PVP amount obviously reduce adhesion of bacteria. ► The film has little cytotoxicity as AgNO3 concentration is below 0.25 mM. ► The film exhibits strong and long-acting bactericidal activity towards bacteria.