We report the use of
zirconium phosphate (ZrP) nanoplatelets for the encapsulation of the anticancer
drug cisplatin and its delivery to
tumor cells.
Cisplatin was intercalated into ZrP by direct ion exchange and was tested in vitro for cytotoxicity in the human
breast cancer (MCF-7) cell line. The structural characterization of the intercalated
cisplatin in ZrP suggests that during the intercalation process, the
chloride ligands of the
cisplatin complex were substituted by
phosphate groups within the layers. Consequently, a new
phosphate phase with the
platinum complex directly bound to ZrP (cisPt@ZrP) is produced with an interlayer distance of 9.3 Å. The in vitro release profile of the intercalated
drug upon a pH stimulus shows that at low pH under lysosomal conditions the
platinum complex is released with simultaneous hydrolysis of the
zirconium phosphate material, while at higher pH the complex is not released. Experiments with the MCF-7 cell line show that cisPt@ZrP reduced the cell viability up to 40%. The cisPt@ZrP intercalation product is envisioned as a future nanotherapy agent against
cancer. Taking advantage of the shape and sizes of the ZrP particles and controlled release of the
drug at low pH, it is intended to exploit the enhanced permeability and retention effect of
tumors, as well as their intrinsic acidity, for the destruction of malignant cells.