Formation of Calcium Phosphate Whiskers in Hydrogen Peroxide (H2O2) Solutions at 901C

A novel, one-pot technique of synthesizing calcium phosphate whiskers was developed. Commercially available b-tricalcium phosphate (b-Ca3(PO4)2) powders were aged in unstirred 30% H2O2 solutions at 901C for 48 h in ordinary glass media bottles. Resultant samples consisted of whiskers (200 nm wide and 5 lmlong) of a biphasic mixture of octacalcium phosphate (OCP: Ca8H2(PO4)6 . 5H2O) and carbonated apatitic (apatite-like) calcium phosphate (Ap-CaP). As-formed whiskers possessed a Ca/P molar ratio of 1.46 and a BET surface area of 8 m/g. Upon soaking these whiskers in a Tris-HCl-buffered SBF solution of 27 mMHCO3 for 6 days, Ca/P molar ratio and surface area values were increased to 1.60 and 52 m/g, respectively. The technique, owing to its simplicity, may prove useful in providing large amounts of biocompatible short whiskers for numerous technology sectors.