Department of Neutron Activation Analysis Division of Nuclear Physics Frank Laboratory of Neutron Physics Joint Institute for Nuclear Research Biosynthesis of silver and gold nanoparticles using microbial biomass Inga Zinicovscaia E-mail: zing@nf.jinr.ru JINR Scientific Council, September 15-16, 2011 M.V. Frontasyeva, S.S. Pavlov Frank Laboratory of Neutron Physics , JINR, Russian Federation T. Kalabegishvili , E. Kirkesali , I. Murusidze , D. Pataraya, E.N. Ginturi Andronikashvili Institute of Physics, Tbilisi , Georgia I. Zinicovscaia, Gh. Duca Institute of Chemistry of the Academy of Science of Moldova, Chisinau, Moldova Introduction An important area of research in nanotechnology deals with synthesis of nanoparticles of different chemical composition and size. There is a growing need to develop environmentally gentle nanoparticle synthesis that does not use toxic chemicals in its process. As a result, researchers in the field of nanoparticle synthesis have turned to biological systems. It is well known that many organisms, both uni-cellular and multi-cellular, are producing inorganic materials either intra- or extra-cellularly. 3 Advantages of biological method tightly controlled, highly reproducible syntheses biocompatible particles the avoidance of toxic surfactants or organic solvents 4 Biotechnology of silver nanoparticles Application of silver nanoparticles nonlinear optics medicine electronics catalysis microelectronics 6 Experiment + pale yellow AgNO3 1mM = yellowish brown UV-Vis spectra recorded after one week for the reaction mixture prepared using 1mM silver nitrate and 1 g Streptomyces glaucus 71MD 7 Scanning electron microscope Resolution 1.2 nm Magnification 5000–150000x Voltage 1–30 kV Quanta 3D FEG The Netherlands’ Firm “Systems for Microscopy and Analysis” (Moscow, Russia) 8 Objects of study p Blue-green microalga Spirulina platensis Bacteria Streptomyces glaucus 71MD 9 1 day Control SEM micrographs of Spirulina platensis cells with silver nanoparticles 10 C O EDAX spectrum recorded from Spirulina platensis cells after formation of silver nanoparticles 11 150 000x 50000x 000x 12 Control SEM micrographs of Streptomyces glaucus 71MD cells with silver nanoparticles 12 EDAX spectrum of Streptomyces glaucus 71MD cells after exposure to silver nitrate solution 13 Biotechnology of gold nanoparticles Application of gold nanoparticles Catalysis Chemical sensing Biosensing Medicine 15 Experiment + HAuCl4 yellow = red purple Experiment I Experiment II CHAuCl4 = 1mM Incubation time: 1 − 6d Incubation time = constant CHAuCl4: 10-4 − 10-2M 16 UV-Vis spectra recorded after one week for the reaction mixture prepared using 1mM hydrated gold chloride and 1 g biomass of A. globiformis 151B 17 Experiment I 6days days 35days day 21days Control SEM micrographs of Spirulina platensis cells with gold nanoparticles at different incubation time 18 Experiment II HAuCl4 -2M 10 -3-3 5·10 M 10 -4 10 MM SEM micrographs of Spirulina platensis cells with gold nanoparticles at different concentrations 19 EDAX spectrum of Sp. platensis cells after exposure to hydrated gold chloride solution 20 Conclusions 1. Production of silver and gold nanoparticles by blue-green microalgae Spirulina platensis and bacteria Streptomyces glaucus 71MD proceeds extra-cellularly 2. SEM and EDAX were used to characterize the silver and gold nanoparticles. SEM showed formation of nanoparticles in the range of: a) 4–25 nm for Streptomyces glaucus 71MD b) 16–200 nm for Spirulina platensis (first experiment) c) 15 nm–7 μm for Spirulina platensis (second experiment) 21 For quantitative analysis of samples the epithermal neutron activation analysis (ENAA) in the radioanalytical complex REGATA at the reactor IBR-2M will be carried out by the end of 2011 22 Elemental concentration in biomass of Streptomyces glaucus (irradiation time 8 s) Element Energy, keV Concentration, µg/g Error, % Ag 657.76 37 5 K 1524.58 3290 8 La 1596.21 15 14 Mn 846.75 25.0 6 Na 1368.55 381 5 Sb 564.24 1.3 15 The data were obtained by Sergey Pavlov (FLNP JINR) and Arnaud Faanhof (NECSA) in June 2011 at the reactor SAFARI-I 23 Thank you for attention!