Figure 1. Chemical structure of colloidal calcium phosphates. Pure ß-TCP (1) and hydroxyapatite (2) powder were used as standard reference materials. FTIR analysis demonstrated PO₄^3– adsorption peaks around 1000, 600, and 580 cm^–1 attributable to ß-TCP on the precipitate synthesized in m•SBF (3). Peaks around 1000, 600, and 3570 cm^–1, attributed to OH groups, were observed with precipitation of HBSS (4); thus, the precipitate of HBSS was determined as hydroxyapatite. All data were confirmed with 6 different samples, respectively, for each colloidal calcium phosphate.