%0 Journal Article
%T Biosynthesis of Silver Nanoparticles by Marine Invertebrate (Polychaete) and Assessment of Its Efficacy against Human Pathogens
%A Reena Singh
%A Sunil Kumar Sahu
%A Muthusamy Thangaraj
%J Journal of Nanoparticles
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/718240
%X Synthesis of metallic nanoparticles by chemical and physical method makes the process often cumbersome due the usage of toxic and expensive chemicals. The present study reports the biosynthesis of silver nanoparticles using marine invertebrate (polychaete) extract at room temperature. The ultraviolet-visible (UV-Vis) spectroscopy revealed the formation of silver nanoparticles (AgNPs) by exhibiting the typical surface plasmon absorption maximum at 418¨C420£¿nm. Structure and composition of AgNPs were analyzed by atomic force microscopy (AFM). Average particle size of AgNPs ranged from 40 to 90£¿nm, confirmed by scanning electron microscopy (SEM) analysis. The energy-dispersive X-ray spectroscopy (EDX) of the nanoparticles dispersion confirmed the presence of elemental silver signal, whereas X-ray diffraction (XRD) substantiated the crystalline nature of synthesized nanoparticle. Fourier transform infrared spectroscopy (FTIR) spectral analysis showed the presence of amides phenols, ethers, and fatty acids as major biomolecules responsible for the reduction of silver ions. The possible mechanism responsible for the synthesis of AgNPs by these biomolecules was also illustrated by chemical reactions. The synthesized AgNPs showed comparatively good antibacterial activity against the tested human pathogens. This study advocates that not only plants and microbes but also marine invertebrates do have potential for synthesizing nanoparticles by a cost-effective and eco-friendly approach. 1. Introduction Colloidal particles are receiving augmented attention as an important starting point for the fabrication of micro- and nanostructures due to their attractive physical and chemical properties which differ considerably from the bulk phase [1]. The integration of nanomaterials with biology has led to the development of diagnostic devices, various analytical tools, therapeutic applications, and drug delivery vehicles [2]. Silver nanoparticles (AgNPs) have high reactivity due to the large surface to volume ratio and play a crucial role in inhibiting bacterial growth in aqueous and solid media. For instance, AgNPs have been reported to possess antitumour [3], antibacterial [4], antifungal [5], and antiviral activity [6]. The antimicrobial activity of AgNPs is influenced by the dimensions of the particles; usually the smaller the particles, the greater the antimicrobial effect [7]. The production of nanoparticles with desired shape and size can be obtained from simple bacteria to highly complex eukaryotes in the reaction mixture [4, 8]. However, with the development of new
%U http://www.hindawi.com/journals/jnp/2014/718240/