Biogenic synthesis of silver nanoparticles and its synergistic antimicrobial potency: an overview

Abstract

Recent surge in the occurrence of antimicrobial resistance genes among pathogenic microbes has been a course of concern globally. Antimicrobial resistance is one of the major threats to human health warranting research for more potent antimicrobial agents. Nanoparticles are among the most promising novel therapeutic agents that could be used against pathogens that exhibit diverse resistance to antibiotics. In particular, silver nanoparticles were shown to exhibit great antimicrobial potency. In contrast to chemical synthesis, plant extracts synthesized silver nanoparticles have no known setbacks. The extracts caused the reduction of the metallic silver, formulation and stabilization of the nanoparticles. This review has described that nanoparticles structure, particle size and its zeta (ζ) potential are among the major factor that influence its antimicrobial activity. In fact, as particle size decreases, the surface area-to-volume ratio greatly increases thus effecting maximum efficacy. The review has presented in details on the biogenic synthesis of silver nanoparticles while extensively exploring the mechanisms behind such antimicrobial potency. It is hope the review will provide a reference information to both students and researchers as well as served as a guide for policy makers in decision making regarding the possibility of using silver nanoparticles as antimicrobial agents.