A multi-photoresponsive molecular-hybrid for dual-modal photoinactivation of cancer cells

We report the design, synthesis, photochemical characterization and biological evaluation of a novel molecular conjugate in which two chromogenic centers, a porphyrin unit and a nitroaniline derivative, are covalently linked through an alkyl spacer. This molecular hybrid can be encapsulated in biocompatible, water soluble polymer nanoparticles where it shows satisfactory fluorescence emission and capability to generate simultaneously the cytotoxic singlet oxygen and nitric oxide upon excitation with visible light. The photoactive nanoassembly can be delivered to A375 melanoma cancer cells where it can be detected through its red fluorescence, and is capable of inducing amplified cell mortality by bimodal action due to the concomitant photoproduction of reactive oxygen and nitrogen oxygen species.