  This study presents a complete structural and biological characterization of
Doxorubicin CaCO3 single crystals as a pH responsive drug carrier. Using a
biomimetic approach, it was demonstrated that calcite single crystals are able,
during their growth in presence of doxorubicin, to entrap drug molecules inside
their lattice, along specific crystallographic directions. High resolution
synchrotron powder diffraction measurements allowed the determination of the
lattice distortion and microstructural parameters. Confocal microscopy
confirmed that doxorubicin is uniformly embedded in the crystal and that the
drug is not only adsorbed on the crystal surface. A slow release of DOX is
obtained that occurs preferentially in proximity of the crystals, targeting
cancer cells.
