Targeting cancer cells through iron(III) complexes of di(picolyl)amine modified silica core–shell nanospheres

In this report, we aim at optimizing the approach of delivering and imaging cancer cell targeting using anti-proliferative nanoparticle complex. Rhodamine B isothiocyanate doped silica-coated (RBITC-SiO2) were prepared by microemulsion method. Fe(III) complex of di(picolyl)amine was conjugated on to the surface RBITC-SiO2 to produce final nanosphere (RBITC-SiO2@dpa-Fe) with an average hydrodynamic diameter of 74 nm. The Fe(III)-di(picolyl)amine complex modified nanospheres displayed enhanced HeLa cells uptake in vitro suggesting selective cancer cell payload delivery. RBITC-SiO2@dpa-Fe also showed reduced off-target cytotoxicity. The conjugate of dpa-Fe(III) complex and fluorescence core–shell nanoparticles RBITC-SiO2 represents a class of novel multi-functional nanoparticles that combines the advantages of active cancer-targeting through Fe(III) complex mediated intracellular drug delivery and compatibility with fluorescence imaging.