title: Biosynthesis of fluorescent gold nanoparticles using an edible freshwater red alga, Lemanea fluviatilis (L.) C.Ag. and antioxidant activity of biomatrix loaded nanoparticles.
abstract: Biosynthesis of gold nanoparticles has been accomplished via reduction of an aqueous chloroauric acid solution with the dried biomass of an edible freshwater epilithic red alga, Lemanea fluviatilis (L.) C.Ag., as both reductant and stabilizer. The synthesized nanoparticles were characterized by UV-visible, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), and dynamic light scattering (DLS) studies. The UV-visible spectrum of the synthesized gold nanoparticles showed the surface plasmon resonance (SPR) at around 530 nm. The powder XRD pattern furnished evidence for the formation of face-centered cubic structure of gold having average crystallite size 5.9 nm. The TEM images showed the nanoparticles to be polydispersed, nearly spherical in shape and have sizes in the range 5-15 nm. The photoluminescence spectrum of the gold nanoparticles excited at 300 nm showed blue emission at around 440 nm. Gold nanoparticles loaded within the biomatrix studied using a modified 2,2-diphenyl-1-picrylhydrazyl (DPPH) method exhibited pronounced antioxidant activity.
authors.affiliation: Department of Ecology and Environmental Sciences, Assam University, Silchar, 788011, Assam, India.
authors.forename: Banasree
authors.initials: B
authors.lastname: Sharma
authors.forename: Debraj Dhar
authors.initials: DD
authors.lastname: Purkayastha
authors.forename: Subhenjit
authors.initials: S
authors.lastname: Hazra
authors.forename: Moirangthem
authors.initials: M
authors.lastname: Thajamanbi
authors.forename: Chira R
authors.initials: CR
authors.lastname: Bhattacharjee
authors.forename: Narendra Nath
authors.initials: NN
authors.lastname: Ghosh
authors.forename: Jayashree
authors.initials: J
authors.lastname: Rout
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D001709:Biotechnology / Q000379:methods; D005618:Fresh Water; D006046:Gold / Q000737:chemistry*; D055772:Green Chemistry Technology; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D011208:Powders; D000461:Rhodophyta / Q000378:metabolism*; D012542:Scattering, Radiation; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D000975:Antioxidants; D011208:Powders; D006046:Gold