Microwave-assisted hydrothermal preparation using adenosine 5′-triphosphate disodium salt as a phosphate source and characterization of zinc-doped amorphous calcium phosphate mesoporous microspheres

Zinc-doped amorphous calcium phosphate (Zn/ACP) mesoporous microspheres have been prepared using CaCl2, ZnCl2 and adenosine 5'-triphosphate disodium salt (ATP) as a biocompatible organic phosphorus source by a microwave-assisted hydrothermal method. Both ATP and Zn2+ are reported as the stabilizer for amorphous calcium phosphate (ACP) in aqueous solution. In this study, we have found that ATP is the main factor for stabilizing ACP in aqueous solution and Zn2+ ions are doped in ACP for the antibacterial benefit. X-ray powder diffraction (XRD), scanning electron microscopy (SEM), nitrogen adsorption-desorption isotherm and pore size distribution, Fourier transform infrared (FTIR) spectroscopy and thermogravimetry (TG) analysis are used to characterize the as-prepared Zn/ACP mesoporous microspheres. The TG and FTIR results reveal that some residual ATP molecules are adsorbed on the surface of the Zn/ACP mesoporous microspheres. The pH-sensitive Zn2+ ion release behavior and good antibacterial activity of Zn/ACP mesosporous microspheres against bacteria Staphylococcus aureus and Escherichia coli indicate that the as-prepared Zn/ACP mesoporous microspheres are promising for the antibacterial application in the biomedical fields. (C) 2013 Elsevier Inc. All rights reserved.