Green synthesis of silver nanoparticles with enhanced antibacterial activity using holocellulose as a substrate and reducing agent

Abstract

Silver nanoparticles (AgNPs) with relatively uniform size and well-defined structure have been synthesized by a hydrothermal method with holocellulose (HC) as a substrate and reducing agent for silver ions. This method was simple, cost-effective and convenient to handle without use of any other stabilizing or reducing agents. The as-prepared HC/Ag nanocomposites exhibited good cytocompatibility to cells and were highly toxic to microorganisms. The antibacterial activity studies were carried out on both Gram-positive S. aureus and Gram-negative E. coli bacteria by a disc diffusion method and an agar dilution method. The important role of HC and the influence of the additional reducing agents (NaBH₄ and ascorbic acid) on the products were systematically investigated, and the formation mechanism of HC/Ag nanocomposites was proposed. These results indicate that HC is a good candidate for the preparation of silver-based nanocomposites, and the as-prepared HC/Ag nanocomposites may have potential for use in a wide range of biomedical applications.