title: Biosynthesis of bismuth nanoparticles using Serratia marcescens isolated from the Caspian Sea and their characterisation.
abstract: Today, synthesis of nanoparticles (NPs) using micro-organisms has been receiving increasing attention. In this investigation, a bismuth-reducing bacterium was isolated from the Caspian Sea in Northern Iran and was used for intracellular biosynthesis of elemental bismuth NPs. This isolate was identified as non-pigmented Serratia marcescens using conventional identification assays and the 16s rDNA fragment amplification method and used to prepare bismuth NPs. The biogenic bismuth NPs were released by liquid nitrogen and highly purified using an n-octanol water two-phase extraction system. Different characterisations of the purified NPs such as particle shapes, size and purity were carried out with different instruments. The energy-dispersive X-ray and X-ray diffraction (XRD) patterns demonstrated that the purified NPs consisted of only bismuth and are amorphous. In addition, the transmission electron micrograph showed that the small NPs formed larger aggregated NPs around <150 nm. Although the chemical syntheses of elemental bismuth NPs have been reported in the literature, the biological synthesis of elemental bismuth NPs has not been published yet. This is the first report to demonstrate a biological method for synthesising bismuth NPs and their purification with a simple solvent partitioning method.
authors.affiliation: Tehran University of Medical Sciences, Department of Pharmaceutical Biotechnology and Biotechnology Research Centre, Tehran, Iran.
authors.forename: P
authors.initials: P
authors.lastname: Nazari
authors.forename: M A
authors.initials: MA
authors.lastname: Faramarzi
authors.forename: Z
authors.initials: Z
authors.lastname: Sepehrizadeh
authors.forename: M R
authors.initials: MR
authors.lastname: Mofid
authors.forename: R D
authors.initials: RD
authors.lastname: Bazaz
authors.forename: A R
authors.initials: AR
authors.lastname: Shahverdi
mesh_terms: D001729:Bismuth / Q000737:chemistry*; D005618:Fresh Water / Q000737:chemistry; D059625:Liquid-Liquid Extraction / Q000379:methods; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D012623:Seawater / Q000737:chemistry; D012706:Serratia marcescens / Q000302:isolation & purification / Q000378:metabolism*; D014961:X-Ray Diffraction
chemical_list: D001729:Bismuth