Formation of calcium phosphate whiskers in hydrogen peroxide (H2O2) solutions at 90°C

A novel, one-pot technique of synthesizing calcium phosphate whiskers was developed. Commercially available beta-tricalcium phosphate (beta-Ca-3(PO4)(2)) powders were aged in unstirred 30% H2O2 solutions at 90 degrees C for 48 h in ordinary glass media bottles. Resultant samples consisted of whiskers (200 nm wide and 5 mu m-long) of a biphasic mixture of octacalcium phosphate (OCP:Ca8H2(PO4)(6) center dot 5H(2)O) 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(2)/g. Upon soaking these whiskers in a Tris-HCl-buffered SBF solution of 27 mM HCO3- for 6 days, Ca/P molar ratio and surface area values were increased to 1.60 and 52 m(2)/g, respectively. The technique, owing to its simplicity, may prove useful in providing large amounts of biocompatible short whiskers for numerous technology sectors.