Photophysical Exploration of Dual-Approach Pt^II-BODIPY Conjugates: Theoretical Insights

Two-component Pt^II-BODIPY dyes were recently proposed as potential multitarget agents able to conjugate the photobased photodynamic therapy (PDT) treatment with the classical chemotherapy approach based on Pt^II complexes. A careful first-principle investigation is herein presented on the above-mentioned conjugates (Pt-1 and Pt-2) and on the two metal-free precursors (1 and 2), aimed at revealing the influence of the platinum moiety on the physicochemical behavior of the photosensitizer (PS) and to inspect, in turn, the possible modulation of the hydrolysis rate of the Pt^II ligand induced by the PS. The investigated photophysical properties for singlet and triplet states and the amplitude of the computed spin-orbit matrix elements reveal that the Pt-containing systems are able to enhance the cytotoxic ¹O₂ production. The Pt^II moiety, instead, follows an activation mechanism similar to that previously found for cisplatin and its analogues already used in cancer therapy.