A red-emissive AIE-active cycloiridium(III)-butyltin(IV) heteronuclear complex: Evaluation for A549 cancer cell theranostics.

Although cycloiridium(III) complexes and organotin(IV) compounds exhibited potential in anticancer therapy, their commonly observed aggregation-caused quenching (ACQ) effect limited the determination of targeting and anticancer mechanisms. This issue could be effectively overcome by introducing the aggregation-induced emission (AIE) concept. In this study, an AIE-active cycloiridium(III)-tributyltin(IV) imidazole phenanthroline complex (IrSn) with red-emission (677 nm) was prepared. The red emission and AIE properties of IrSn enabled more convenient investigation of its cellular uptake mechanism (energy-dependent) and intracellular localization (mitochondria-targeted). Additionally, compared with cycloiridium(III) and organotin(IV) monomers, IrSn exhibited significantly superior in-vitro antiproliferative activity towards A549 cells, including cisplatin-resistant A549/DDP cells. Collectively, IrSn provided a fundamental structural model for the development of non‑platinum metal anticancer agents as alternatives to platinum-based drugs, and holding potential applications in the theranostic system of A549 cells.