The design and synthesis of calcium phosphates (CPs) nanostructures with high specific surface areas are significant for drug delivery systems. Herein, we report a simple surfactant-free sonochemical synthesis of carbonate apatite (CAP) nanorod bundles with a high specific surface area (183.39 m(2) g(-1)) using an aqueous solution of CaCl2-2H(2)O and (NH4)(2)HPO4. The effects of experimental parameters including reactant species, pH value, calcium ion concentration, reaction time on the specific surface area of the product were investigated. The products were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The as-prepared CAP nanorod bundles were explored as the drug nanocarrier, which exhibited a sustained drug release behavior in simulated body fluid. (C) 2012 Elsevier Ltd. All rights reserved.