A New Hetero‐Bimetallic [Fe(III)‐Mn(I)] Complex as a Dual Modality, Theranostic Tool for Photoactivated Anticancer Therapy

Abstract

We developed a novel hetero‐bimetallic Fe(III)‐Mn(I) complex by combining hydroxyl radicals generating Fe(III)‐Phenolato/Carboxylato and CO‐releasing Mn(I)(CO)3 complexes to achieve a dual‐modality theranostic tool for photoactivated anticancer therapy. Fe(III)‐Phenolato/Carboxylato and Mn(I)(CO)3 complexes were conjugated through the amide coupling to synthesize the bimetallic Fe(III)‐Mn(I) complex ([Fe‐Mn]) and characterized analytically and spectroscopically. Various photophysical assays have confirmed the production of hydroxyl radicals and the release of CO when the biologically benign [Fe‐Mn] complex is activated by visible light (400–700 nm), resulting in a significant increase in luminescence intensity. The cytotoxic potential of the complex, [Fe‐Mn] resulted from the photoactivated enrichment of ROS and CO in the A549 cells with the photoindex of ~35 leaving HPL1D cells unaffected. We probed the caspase 3/7‐dependent apoptosis and the theranostic potential of the complex, [Fe‐Mn] on photoactivation in vitro. The hetero‐bimetallic Fe(III)‐Mn(I) complex ([Fe‐Mn]) provides an ideal example of a dual‐modality next‐generation theranostic tool for photoactivated anticancer therapy.