Apatite growth on calcium adsorbed surface of wet flocculated silica particles immersed in a modified simulated body fluid

An alternative method for the calcium phosphate apatite formation onto the surface of flocculated pure silica particles is reported, in an attempt to understand the possible mechanism for the apatite formation. A stable silic a sol was flocculated by adding calcium ions in aqueous solution. The wet f locks were resuspended in a basic aqueous solution containing a calcium sal t, trying to allow the absorption of calcium ions onto the silica surface t hrough a hydrogen ion exchange. The as-prepared materials were immersed in a modified simulated body fluid at different temperatures (37 and 90 degree s C) and silica concentrations, It was found that these factors have a stro ng influence on the apatite formation, The apatite formation was confirmed by P-31 MAS-NMR, FT-Raman, XRD, and TEM, (C) 2000 John Wiley & Sons, Inc.