Page 55 - PR 2014 2016 10 Materials and Nanotechnology

Materials and Nanotechnology | Progress Report 331
Bifunctional magnetic and luminescent
nanoparticles for diagnostic and
theranostic.
The design of bifunctional luminescent
magnetic nanomaterials containing MFe O
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(where M=Fe and Mn) doped with rare earth
and functionalized with rare earth ions in-
clusion complexes of calixarene and phos-
phine oxide and also β-diketonate ligands
or chitosan natural polymer and quantum
dots have been investigated. These novel
kind of luminescent magnetic nanomaterials
(MFe O @QD,Ln) complexes/compound pres-
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ent very interesting superparamagnetic and
photonic properties. The magnetic properties
were explored at 5 and 300K temperature
and showed that extent of coating and crys-
tallinity affect the saturation magnetization
values of nanoparticles. Although ferrite is a
strong luminescence quencher, the coating
of the MFe O nanoparticles has overcome
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this difficulty. The intramolecular energy
transfer in the nanomaterials from the T1
excited triplet states of TTA and ACAC li -
5
5
3+
3+
gands to the D (Eu ) and D (Tb ) emitting
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Figure 65. Synthesis protocol of MnFe O @CH-Eu(TTA) (TPPO) (left); MnFe O @CH-Eu(TTA) (TPPO) composite, and the composite under effect
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4
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2
of magnetic field(upper -right); Magnetization curve of MnFe O @CH-Eu(TTA) (TPPO) inserted fig solution of chitosan and complex under
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4
366nm excitation (down-right).
levels has been determined. In addition to
the superparamagnetic behavior, these nano-
phosphors may act as emitting layer of red
and green light converting molecular devices
(LCMDs) and are responsible for new ways
in the diagnostic and teranostic field. This
research has been developed in collaboration
with the LNLS, Chemistry institute of Univer-
sity of São Paulo and Campinas University
(Figure. 65).
Luminescent material associated to a
metal nanoparticles and Plasmon effect
The use of these metallic nanostructures to
favorably modify the optical properties of
fluorophores in order to increase the intensity
of fluorescence emission. The project aims
to synthesize metallic nanoparticles using
green chemistry and use these nanoparticles
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0
in photonic materials. Particles of Ag , Au
and Cu are produced using green chem -
0
istry protocols and then are associated to
luminescent materials based on lanthanides
to improve the efficiency of the materials
luminescence. They are now being targeted
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