Electrochemical synthesis of chitosan/silver nanoparticles multilayer hydrogel coating with pH-dependent controlled release capability and antibacterial property

By coupling in situ electrochemical synthesis of silver nanoparticles (AgNPs) with the pre-deposited chitosan multilayer hydrogel, a novel type of nanocomposite coating was successfully fabricated on the stainless-steel needle electrode. Experimental results demonstrated the chitosan film can serve as a versatile medium for metal salt adsorption and stabilization, and finally electrochemical reduction of loaded silver ions to nanoparticles. The AgNPs were fabricated with a spherical shape and an average size of similar to 15 nm endowing considerable antibacterial property to the hydrogel. Furthermore, the unique layered architecture consisted of porous segments and compact boundaries is almost retained, resulting in a pH-dependent and staged release pattern of silver nanoparticles based on acid triggered dissolution of the multi-membrane layer by layer. Thus, considering the mild synthesizing approach, multi-functionalities and relatively low cytotoxicity, this antibacterial hydrogel would show great potential either to be used as a newly coating material for interfacial improvement of implants or as a free-standing film after being peeled off for wound dressing.

Automated summary

A novel nanocomposite coating was successfully fabricated on the stainless-steel needle electrode by coupling in situ electrochemical synthesis of silver nanoparticles with pre-deposited chitosan multilayer hydrogel. The coating exhibited considerable antibacterial property and a pH-dependent and staged release pattern of silver nanoparticles.