Study by Spectroscopy Raman of nanoparticles
strontium phosphate obtained by different thermal
treatments
Janaína S. Rochaa , Elayne V. Carvalhob, Pierre B. A. Fechineb
a
Laboratório de Materiais Funcionais Avançados (LaMFA), Departamento de Física, Universidade Federal do
Ceará, P.O. Box 6030, 60455-900, Fortaleza-CE, Brazil
b
Group of Chemistry of Advanced Materials (GQMAT) – Department of Analytical Chemistry and Physicchemistry, Federal University of Ceará – UFC, Campus do Pici, CP 12100, Zip Code 60451-970, Fortaleza,
Brazil.
In recent years, interest in the properties and effects of biomaterials based strontium has
increased due to its similarity with calcium [1]. In addition to excellents bioactivity and
biocompatibility, the capability of Sr2+ ions to stimulate the differentiation of osteoblast
progenitor cells, limit osteoclastic resorption, and enhance the radiopacity of calcium
phosphates (CaPs) [2]. Strontium of phosphate powders were obtained by co-precipitation
and submitted to different thermal treatments (SrHap, SrHap2h, SrHap5h, SrHap600,
SrHap700 and SrHap800). Several phases were produced and evaluated. Therefore, the aim
of this work was to synthesize and employ specific calcium phosphates nanoparticles into
the biomaterials. Strontium hydroxyapatite nanoparticles (SrHAp5h) were successfully
prepared using a hydrothermal method. The crystallinity, crystallite size and morphology of
the nanoparticles were characterized through XRD, FT-IR, Raman and TEM. Raman spectra
(Figure 2 (A)) collected from samples and in all the spectra it is possible to observe the
presence of a mode with very high intensity at approximately 950 cm-1 originating from
symmetric stretching vibrations of O–P–O bonds with free tetrahedral phosphate ion
associating SrHAp. The internal Raman vibrations of phosphate carbonate and hydroxyl ions
in apatite appear above 400 cm-1. Additionally, bands at approximately 420, 575 and 1030
cm-1 correspond to characteristic stretching symmetric of PO43- groups in SrHAp. The band
at about 1047 cm-1 can be assigned to CO32- stretching vibration modes [3]. FT- IR spectra
(Figure 2 (A)) confirms the presence of the species PO 43- and CO32- and a large band at
~3500 indicates H2O into all samples. TEM micrographs of the SrHAp nanoparticles
showed nanorod shape with increasing crystallinity and size.
(B)
(A)
R
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Wavenumber (cm-1)
Wavenumber (cm-1)
Figure 1 (A) Raman and (B) FTIR spectra of powders obtained.
REFERENCES
[1] P. Habibovic; J.E. Barralet. Bioinorganics and biomaterials: Bone repair. Ata
Biomaterialia. 2011; 7: 3013 - 3026.
[2] Satish S. Singh et al. Murine osteoblastic and osteoclastic differentiation on strontium
releasing hydroxyapatite forming cements. Materials Science and Engineering C. 2016; 63:
429–438.
[3] Valentina Aina et al. Magnesium- and strontium-co-substituted hydroxyapatite: the
effects of doped-ions on the structure and chemico-physical properties. J Mater Sci: Mater
Med. 2012; 23:2867–2879.