Growth of calcium phosphate onto coagulated silica prepared by using modified simulated body fluids

Silica sols prepared by the alkaline hydrolysis of tetraethylorthosilicate were coagulated by adding an excess of a CaCl2 aqueous solution. The,aggreg ates were immersed into three different modified simulated body fluids at 9 0 degrees C to allow the growth of a calcium phosphate phase onto the silic a aggregates. The apatite phase grew faster compared to previous studies. A lso, the amount of the crystalline apatite yield was higher when the simula ted body fluid employed had the largest Ca/P ratio, as measured by X-ray di ffraction. The relevance of these findings is discussed in terms of the cur rent and future trends in biomaterials research and development.