Calcium phosphate (CaP) minerals,such as hydroxyapatite (Ca10(PO4)6(OH)2,HAp),are the main inorganic constitutes of human bone and tooth.Moreover,the synthetic HAp with various nanostructures has been widely used as organic drug carriers,adsorbents for separation/purification of biomolecules,and catalysts supports owing to the unique surface chemistry such as a hydrophilic nature and good affinity for various organic molecules.