Enhanced photocytotoxicity induced by a platinum diimine complex employing amine-functionalized magnetite-silica nanocomposites as delivery vehicles

Core-shell magnetite-silica nanocomposites modified with 3-aminopropyltriethoxy silane (APTES) were prepared by silanization reaction, and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy and dynamic light scattering. Then the nanocomposites were employed as carriers of a photoactive platinum diimine complex. Photoinduced cytotoxicity by the photosensitizer-loaded nanocomposites in different human carcinoma cells has been studied by cell viability assay. The cellular uptake of the photosensitizer-loaded nanocomposites has also been studied by ICP-MS. The results suggest that the cytotoxicity induced by the platinum diimine complex in red light can be greatly enhanced when the photosensitizer is loaded with the magnetic nanocomposites, and the surface charge of the nanocomposites may also have effect on the photocytotoxicity of the photosensitizer.