Page 40 - PR 2014 2016 10 Materials and Nanotechnology

316 Materials and Nanotechnology | Progress Report

Nanotechnology structures and a high specific surface area

(about 574m /g) (Figure 45).
2
Novel fluorescent, crystalline and
mesoporous beta tricalcium phosphate These special nanoparticles become fluores-
nanoparticles cent when doped with Europium ions. The Eu/

Mg:β-TCP has an efficient visible luminescence
Synthetic calcium phosphates, especially hy- and constitutes a new nanoprobe that can
droxyapatite (Ca (PO ) (OH) ) and beta-tricalci- be used as optical contrast agents, affording
10 4 6 2
um phosphate (Ca (PO ) ), are of special interest
3 4 2
in medicine because of their biVompatibility,
bioactivity, non-cytotoxicity and their similar-
ity with human bone and teeth. Due to their
excellent biological functions and responses in
physiological environments, particular atten-
tion has been placed to β–tricalcium phosphate,
which has being widely used in a number of
biomedical applications such as orthopedics,
dentistry, tissue engineering, and drug, gene
and protein delivery.

A novel and stable nanosized magnesium-sub-
stituted beta-tricalcium phosphate (Mg:β-TCP)
was synthesized by an aqueous precipitation
method, at room temperature, in one single
step, for the first time, resulting in a crystal- Figura 46: Eu and Mg doped β-TCP nanopowders after thermal
line and spherical nanoparticles (diameter treatment at (A) 1000°C for 30 seconds and (B) 950°C for 3 minutes.
And (C) shows the emission spectrum of Eu/Mg:β-TCP before (as-syn-
of approximately 20nm), with mesoporous thesized) and after thermal treatments, under excitation at 394nm.

Figure 45: TEM micrographies of Mg:β-TCP (A) as-synthesized and (B) after thermal treatment at 1000°C for 30 seconds.

Instituto de Pesquisas Energéticas e Nucleares