Porous calcite CaCO3 microspheres: Preparation, characterization and release behavior as doxorubicin carrier.

Porous CaCO3 microspheres are nowadays extensively used as a drug delivery system due to their excellent biocompatibility and degradability. However, the stability of vaterite CaCO3 microspheres is a major problem as a drug carrier. In this work, porous calcite CaCO3 microspheres are fabricated by calcination of gelatin-CaCO3 composite microspheres at 550 °C in air. The size and morphology of CaCO3 microspheres could be well regulated by the addition of gelatin. The structure of the as-prepared porous calcite CaCO3 microspheres is characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Compared with vaterite CaCO3 microspheres, porous calcite CaCO3 microspheres are more stable and exhibit good drug-loading and drug release properties for doxorubicin (DOX), an effective anticancer agent. This study provides an easy and novel approach to prepare stable porous calcite CaCO3 microspheres, which show promising potential as a carrier for DOX.