title: Extracellular biosynthesis and characterization of silver nanoparticles using Aspergillus flavus NJP08: a mechanism perspective.
abstract: The present study demonstrates an eco-friendly and low cost protocol for synthesis of silver nanoparticles using the cell-free filtrate of Aspergillus flavus NJP08 when supplied with aqueous silver (Ag+) ions. Identification of the fungal isolate was based on nuclear ribosomal DNA internal transcribed spacer (ITS) identities. Transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) revealed the formation of spherical metallic silver nanoparticles. The average particle size calculated using Dynamic Light Scattering measurements (DLS) was found to be 17±5.9 nm. UV-Visible and Fourier transform infrared (FTIR) spectroscopy confirmed the presence of extracellular proteins. SDS-PAGE profiles of the extracellular proteins showed the presence of two intense bands of 32 and 35 kDa, responsible for the synthesis and stability of silver nanoparticles, respectively. A probable mechanism behind the biosynthesis is discussed, which leads to the possibility of using the present protocol in future "nano-factories".
authors.affiliation: Centre for Biotechnology, Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Rajasthan 333031, India.
authors.forename: Navin
authors.initials: N
authors.lastname: Jain
authors.forename: Arpit
authors.initials: A
authors.lastname: Bhargava
authors.forename: Sonali
authors.initials: S
authors.lastname: Majumdar
authors.forename: J C
authors.initials: JC
authors.lastname: Tarafdar
authors.forename: Jitendra
authors.initials: J
authors.lastname: Panwar
mesh_terms: D001231:Aspergillus flavus / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism / Q000502:physiology; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D012834:Silver / Q000737:chemistry*; D012835:Silver Nitrate / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D005656:Fungal Proteins; D012834:Silver; D012835:Silver Nitrate