Effect of temperature on crystallinity of carbonate apatite foam prepared from α-tricalcium phosphate by hydrothermal treatment
Issue title: Selected papers presented at the International Symposium on Nanotoxicity Assessment and Biomedical Environmental Application of Fine Particles and Nanotubes, Hokkaido, Japan, 16–17 June 2008, Part 2
Affiliations: Department of Biomaterials, Faculty of Dental Science, Kyushu University, Fukuoka, Japan | Section of Bioengineering, Department of Dental Engineering, Fukuoka Dental College, Fukuoka, Japan
Note: [] Address for correspondence: Akari Takeuchi, PhD, Department of Biomaterials, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. Tel.: +82 92 642 6346; Fax: +82 92 642 6348; E-mail: takeuchi@dent.kyushu-u.ac.jp.
Abstract: The effect of temperature on crystallinity of carbonate apatite (CAp) foam prepared from α-tricalcium phosphate (α-TCP) foam by hydrothermal treatment was investigated in the present study. The α-TCP foams were prepared through a conventional sintering method using polyurethane foam as template. Then, the resultant α-TCP foams were hydrothermally treated with Na2CO3 aqueous solution at 100°C, 150°C and 200°C for 72 h. After hydrothermal treatment, the cancellous bone-like macroporous structure of the α-TCP foams was maintained. However, microscopic morphology of the foams' frame significantly changed after the 72 h treatment period. The smooth surface of α-TCP foam disappeared and the whole surface was covered with plate-like deposits. The plate-like deposits treated at 150°C and 200°C had smooth surface while those treated at 100°C were constructed from spherical particles of approximately 200 nm in diameter. The results of X-ray diffraction and Fourier transform infrared analysis showed that α-TCP was completely converted to CAp and the crystallinity of CAp prepared at 100°C was significantly lower than those prepared at 150°C and 200°C. Hydrothermal treatment of α-TCP foam at 100°C allowed the formation of low-crystalline CAp foam but complete conversion needs a longer treatment period.
