Fluoridated apatite synthesized using a multi-step fluoride supply system

Citation
M. Okazaki et al., Fluoridated apatite synthesized using a multi-step fluoride supply system, BIOMATERIAL, 20(14), 1999, pp. 1303-1307
Citations number
21
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Multidisciplinary
Journal title
BIOMATERIALS
ISSN journal
0142-9612 → ACNP
Volume
20
Issue
14
Year of publication
1999
Pages
1303 - 1307
Database
ISI
SICI code
0142-9612(199907)20:14<1303:FASUAM>2.0.ZU;2-U
Abstract
Fluoridated apatite was synthesized at 80 +/- 1 degrees C, pH 7.4 +/- 0.2, using a 5-step fluoride supply system. During the synthesis experiment, 0, 5, 10, 15 and 20 mmol/l of fluoride were each supplied for one-fifth of the experimental period with calcium and phosphate. X-ray diffraction analysis showed a typically apatitic pattern,although the (3 0 0) reflection was br oader than that of homogeneous fluorapatite. Scanning electron micrographic observation indicated that the apatite was composed of needle-like crystal s similar to hydroxyapatite and fluorapatite. High-resolution transmission electron microscopy showed a slender hexagonal shape similar to homogeneous hydroxyapatite in cross-sections perpendicular to the c-axis and the struc tural damage in the core of the crystal, although no boundary of step-like layers was observed. The apparent solubility in 0.5 mol/l acetate buffer so lution (37 degrees C and pH 4.0) was 12.1 +/- 0.2 mmol/l, much less than th at of homogeneous hydroxyapatite 32.3 +/- 1.9 mmol/l, and similar to that o f heterogeneous two-layer fluoridated apatite with an outer fluoride-rich l ayer 12.5 +/- 0.6 mmol/l, which was synthesized previously by supplying flu oride during the latter half of the experimental period. (C) 1999 Elsevier Science Ltd. All rights reserved.