Designing Highly Stable Coordination-Driven Metallacycle for Imaging-Guided Photodynamic Cancer Theranostics
Coordination-driven self-assembly features good predictability and directionality in the construction of discrete metallacycles and metallacages with well-defined sizes and shapes, but their medicinal application has been limited by the low stability and solubility. Herein, we have designed and synthesized a highly stable coordination-driven metallacycle with desired functionality derived from a perylene-diimide ligand via a spontaneous deprotonation self-assembly process. Brilliant chemical stability and singlet oxygen production ability of this emissive octanuclear organopalladium macrocycle make it a good candidate toward biological study. After cellular uptake by endocytosis, the metallocycle exhibits potent fluorescence cell imaging property and cancer photodynamic therapeutic ability through enhancing ROS production, with high biocompatibility and safety. This study not only provides a rational design strategy for highly stable luminescent organopalladium metallacycle, but also sheds light on their application in imaging-guided photodynamic cancer therapy.