Plant-based synthesis of silver nanoparticles and their characteristic properties

Biosynthesised metallic nanoparticles (NPs) have a wide range of applications in the fields of medicine and engineering. Among various metallic NPs, silver (Ag) NPs have gained extraordinary fame due to their unique properties. Conventional methods for the synthesis of silver NPs are pernicious due to chemical toxicity and various serious biological concerns. Plant extract-mediated synthesis can rapidly and simply produce eco-friendly, well-dispersed and stable silver NPs from silver nitrate in aqueous conditions without employing any reducing and stabilising agent. This paper intends to present an overview of the potential use of various plants for silver NP synthesis with particular emphasis on the extraordinary anticancer and antimicrobial properties of these NPs against a wide range of cancerous cell lines and bacterial strains. Several plant extracts have naturally biodegradable antioxidants which simultaneously act as reducing and stabilising agents for silver NP. Furthermore, this paper highlights optimum situations for the green synthesis of silver NPs by controlling critical parameters, such as pH, temperature, duration of incubation and concentrations of both silver salt and plant extract. Hence, green synthesis of silver NPs is a promising method which allows for synthesis with low cost and low energy requirement.