Multifunctional AIE iridium (III) photosensitizer nanoparticles for two-photon-activated imaging and mitochondria targeting photodynamic therapy

• Published in: Journal of nanobiotechnology Vol. 19; no. 1; pp. 254 - 13
• Main Authors: Cai, Xuzi, Wang, Kang-Nan, Ma, Wen, Yang, Yuanyuan, Chen, Gui, Fu, Huijiao, Cui, Chunhui, Yu, Zhiqiang, Wang, Xuefeng
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 23.08.2021; BioMed Central; BMC
• Subjects: Animals; Anticancer properties; Antitumor activity; Apoptosis; Apoptosis - drug effects; Bioavailability; Biocompatibility; Cancer; Cell Death; Cell Line, Tumor; Cyclometalated iridium nanoparticles; Cytotoxicity; Diagnostic Imaging; Female; Fluorescence imaging; Health aspects; Homeostasis; Hydrogen-Ion Concentration; Iridium; Iridium - pharmacology; Laser scanning microscopy; Localization; Medical imaging; Medical research; Medicine, Experimental; Methods; Mice; Mice, Inbred BALB C; Mice, Nude; Mitochondria; Mitochondria - drug effects; Mitochondria-targeted; Molecular targeted therapy; Nanomedicine; Nanoparticles; Nanoparticles - chemistry; Particle size; Penetration depth; Photochemotherapy; Photochemotherapy - methods; Photodynamic therapy; Photons; Photosensitizing Agents - pharmacology; Photosensitizing compounds; Physiology; Production processes; Reactive oxygen species; Technology application; Toxicity; Two-photon excitation; China; Mitochondria-targeted; Fluorescence imaging; Photodynamic therapy; Two-photon excitation; Cyclometalated iridium nanoparticles
• ISSN: 1477-3155; 1477-3155
• DOI: 10.1186/s12951-021-01001-4

Developing novel photosensitizers for deep tissue imaging and efficient photodynamic therapy (PDT) remains a challenge because of the poor water solubility, low reactive oxygen species (ROS) generation efficiency, serve dark cytotoxicity, and weak absorption in the NIR region of conventional photosensitizers. Herein, cyclometalated iridium (III) complexes (Ir) with aggregation-induced emission (AIE) feature, high photoinduced ROS generation efficiency, two-photon excitation, and mitochondria-targeting capability were designed and further encapsulated into biocompatible nanoparticles (NPs). The Ir-NPs can be used to disturb redox homeostasis in vitro, result in mitochondrial dysfunction and cell apoptosis. Importantly, in vivo experiments demonstrated that the Ir-NPs presented obviously tumor-targeting ability, excellent antitumor effect, and low systematic dark-toxicity. Moreover, the Ir-NPs could serve as a two-photon imaging agent for deep tissue bioimaging with a penetration depth of up to 300 μm. This work presents a promising strategy for designing a clinical application of multifunctional Ir-NPs toward bioimaging and PDT.