title: Preparation and Comprehensive Characterization of a Calcium Hydroxyapatite Reference Material.
abstract: Numerous biological and chemical studies involve the use of calcium hydroxyapatite (HA), Ca10(PO4)6(OH)2. In this study detailed physicochemical characterization of HA, prepared from an aqueous solution, was carried out employing different methods and techniques: chemical and thermal analyses, x-ray diffraction, infrared and Raman spectroscopies, scanning and transmission microscopies, and Brunauer, Emmett, and Teller (BET) surface-area method. The contents of calcium (Ca(2+)), phosphate (PO4 (3-)), hydroxide (OH(-)), hydrogenphosphate (HPO4 (2-)), water (H2O), carbonate (CO3 (2-)), and trace constituents, the Ca/P molar ratio, crystal size and morphology, surface area, unit-cell parameters, crystallinity, and solubility of this HA were determined. This highly pure, homogeneous, and highly crystalline HA is certified as a National Institute of Standards and Technology (NIST) standard reference material, SRM 2910.
authors.affiliation: American Dental Association Foundation, Paffenbarger Research Center, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
authors.forename: Milenko
authors.initials: M
authors.lastname: Markovic
authors.affiliation: National Institute of Dental and Craniofacial Research, NIH, Craniofacial and Skeletal Diseases Branch Research Associate Program at the National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
authors.forename: Bruce O
authors.initials: BO
authors.lastname: Fowler
authors.affiliation: American Dental Association Foundation, Paffenbarger Research Center, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
authors.forename: Ming S
authors.initials: MS
authors.lastname: Tung
keywords: Raman; chemical analysis; crystal size; crystallinity; hydroxyapatite; infrared; morphology; preparation; solubility; surface area; thermal analysis; unit-cell parameters; x-ray diffraction