Page 51 - PR 2014 2016 10 Materials and Nanotechnology
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Materials and Nanotechnology | Progress Report 327
done by the co-precipitation and hydrothermal substances has increased in several fields, in-
methods characterized by SEM, IR, XRD, TGA cluding biomarkers as a tool for immunology
and luminescence spectroscopy. These parti- (fluoroimmunoassays). Nowadays, the use of
lanthanides in the diagnosis of various diseas-
es has become more important through the
development of commercial diagnostic kits.
As main feature, these rare earths can show
a long lifetime, photostability and emission
bands of atomic like behavior and well defined,
in the visible region, demonstrating unique
advantages when compared to other lumines-
cent species. The present research synthesize
rare earth molybdates by the co-precipitation
method as well as characterize these materials
by X-ray diffraction, near infrared spectros-
copy, thermogravimetric analysis, scanning
electronic microscopy, transmission electron-
ic microscopy and luminescent studies. This
research focuses three different studies as
followed :the influence of the vortex speed
variation during co-precipitation in the struc-
Figure 60. Excitation and Emission spectra of SnO /TiO :Eu
3+
2 2 ture of the final product, morphology and lu-
nanoparticles (left up and down) and structures of SnO (right
2
-upper) X-ray powder diffraction (right -middle) chromaticity minescence properties; the influence of the
diagram (right -down ).
annealing temperature also in the structure,
morphology and luminescence properties; and
cles were functionalized by silica using two the influence of concentration of the doping
different methods, that are, the microwave in the luminescence properties. Another im-
and Stöber, facilitating the conjugation with portant step of this research is the functional-
biological entities (Figure 60). ization of nanoparticles using an organosilane
(APTES) to coat and establish points for binding
Figure 60. Excitation and Emission spectra the particles to biological species. It was proved
of SnO /TiO :Eu nanoparticles (left up and that this process was very efficient by the char-
3+
2 2
down) and structures of SnO (right -upper)
2
X-ray powder diffraction (right -middle) chro-
maticity diagram (right -down ).
Synthesis and characterization of
TR (MoO ) @SiO nanoparticles doped
2
2
4 3
with Eu , Tb and Nd for biological
3+
3+
3+
labeling
The interest in using rare earths to investigate
Figure 61. Ilustration of Eu:Y (MoO ) under excitation of UV lamp,
the properties and functions of biochemical 2 4 3
SEM of the Eu:Y (MoO ) and Eu:Y (MoO ) @Si Microwave and
2 4 3 2 4 3
systems as well as to determinate biological Eu:Y (MoO ) @Si Stöber and emission spectra of the Y (MoO ) .
4 3
2
2
4 3
