Multimodal polymer encapsulated CdSe/Fe3O4 nanoplatform with improved biocompatibility for two-photon and temperature stimulated bioapplications.

Multimodal polymer encapsulated CdSe/Fe3O4 nanoplatforms with dual optical and magnetic properties have been fabricated. We demonstrate that CdSe/Fe3O4 nanocapsules (NCs) upon excitation with UV radiation or NIR fs-laser excitation exhibit intense one- or two-photon emission at 535 nm, whereas the combination of an alternating magnetic field and 808 nm IR laser excitation results in heat generation. Since anticancer therapies require relatively high doses of Fe3O4 nanoparticles (NPs) to induce biologically relevant temperature jumps, the therapeutic effects of 0.1 and 1 mg/mL Fe3O4 NCs and CdSe/Fe3O4 NCs were investigated using breast cancer cell lines, ER-positive MCF-7, and triple-negative MDA-MB-231 cells. Improved biocompatibility of CdSe/Fe3O4 NCs compared to Fe3O4 NCs was revealed at higher NCs concentration suggesting safe potential medical applications of CdSe/Fe3O4 NCs. In contrast, 1 mg/mL Fe3O4 NCs were found to be more cytotoxic to MDA-MB-231 than MCF-7 cells through iron-induced oxidative stress, lipid peroxidation, and concomitant ferroptotic cell death. We believe that Fe3O4 NCs-mediated cellular response may be heterogeneous that reflects, at least in part, cancer cell genotype, molecular phenotype, and pathological classification.