HKUST Library Institutional Repository Banner

HKUST Institutional Repository >
Mechanical Engineering >
MECH Journal/Magazine Articles >

Please use this identifier to cite or link to this item: http://hdl.handle.net/1783.1/2183
Title: Theoretical analysis of calcium phosphate precipitation in simulated body fluid
Authors: Lu, Xiong
Leng, Yang
Keywords: Calcium phosphate
Simulated body fluid
Kinetics
Thermodynamics
Issue Date: 2004
Citation: Biomaterials, v. 26, iss. 10, April 2005, p. 1097-1108
Abstract: The driving force and nucleation rate of calcium phosphate (Ca-P) precipitation in simulated body fluid (SBF) were analyzed based on the classical crystallization theory. SBF supersaturation with respect to hydroxyapatite (HA), octacalcium phosphate (OCP) and dicalcium phosphate (DCPD) was carefully calculated, considering all the association/dissociation reactions of related ion groups in SBF. The nucleation rates of Ca-P were calculated based on a kinetics model of heterogeneous nucleation. The analysis indicates that the nucleation rate of OCP is substantially higher than that of HA, while HA is most thermodynamically stable in SBF. The difference in nucleation rates between HA and OCP reduces with increasing pH in SBF. The HA nucleation rate is comparable with that of OCP when the pH value approaches 10. DCPD precipitation is thermodynamically impossible in normal SBF, unless calcium and phosphate ion concentrations of SBF increase. In such case, DCPD precipitation is the most likely because of its highest nucleation rates among Ca-P phases. We examined the influences of different SBF recipes, interfacial energies, contact angle and molecular volumes, and found that the parameter variations do not have significant impacts on analysis results. The effects of carbonate incorporation and calcium deficiency in HA were also estimated with available data. Generally, such apatite precipitations are more kinetically favorable than HA.
Description: Biomaterials © copyright (2004) Elsevier. The Journal's web site is located at http://www.sciencedirect.com/
URI: http://hdl.handle.net/1783.1/2183
Appears in Collections:MECH Journal/Magazine Articles

Files in This Item:

File Description SizeFormat
JBMT915text.pdfpre-published version303KbAdobe PDFView/Open

Find published version via OpenURL Link Resolver

All items in this Repository are protected by copyright, with all rights reserved.