Transcript I. Zinicovscaia

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: [email protected]
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!