Mitochondria-Localized and Aggregation-Induced Near-Infrared Emission Iridium(III) Complexes for Photodynamic Therapy.

In recent years, the optical functional materials of iridium(III) complexes have attracted much attention due to their excellent photophysical properties and potential biomedical applications. Among them, aggregation-induced emission (AIE) properties have shown significant advantages in photodynamic therapy (PDT). In this work, three new iridium(III) complexes with near-infrared emission were designed and synthesized, and their crystal structures were determined. All complexes exhibited significant AIE phenomena. Especially, Ir-1 containing an -NH2 functional group exhibited a unique hollow nanoparticle morphology, excellent mitochondrial targeting ability, and high reactive oxygen species (ROS) efficiency, which is expected to play an important role as a new type of nanoprobe in the field of PDT. The complex has the ability to generate both type I and type II ROS, which makes it a potent photosensitizer for the efficient phototherapy of hypoxic tumors. What is more, the complex has dual functions of PDT and chemotherapy, and their synergistic effect greatly enhances the antineoplastic effects of the reagent.