The obtention of hydroxyapatite (HAp) is reported using brushite (CaHPO4.2H2O) and the skeleton of a starfish (Mellita eduardobarrosoi sp. nov.), primarily composed of magnesian calcite ((Ca,Mg)CO3) as precursors. Stoichiometric amounts of both were reacted under hydrothermal conditions: a pressure of 5.8 MPa and a temperature of 200 degrees C for 2, 4, 6, 8, 10, and 20 h of reaction times. The samples obtained were characterized by means of scanning electron microscopy, X-ray diffraction, infrared spectroscopy, and transmission electron microscopy. Two defined populations of HAp fibers were found: A bundle of fibers 75 mum in length and 1-13 mum in diameter, and a second bundle of fibers 5 mum in length and less than 0.5 mum in diameter. Furthermore, an increase in HAp formation and a Ca/P ratio as a function of reaction time were observed. The growth mechanism of HAp is also discussed.
Bones and teeth of vertebrate animals are constituted by a mineral phase very similar to hydroxyapatite (Ca 10 (PO 4 ) 6 (OH) 2 ), for this reason, this material receives a great attention in the industrial and biological area. The structure and particular properties of the synthetic hydroxyapatite used in the production of artificial bones and teeth are very sensitive to the conditions of synthesis, for which, the studies carried out on the methods of synthesis of hydroxyapatite are very important because they determine the growth of the crystal, morphology, aggregation, nucleation and dissolution properties of hydroxyapatite. The present work was developed in order to establish the effects of reaction time in morphological and structural characteristics of hydroxyapatite.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.