Sonodynamic cancer therapy by novel iridium-gold nanoassemblies

Metal-based compounds with excellent photo-physical properties show good photochemotherapeutic performance. But, low in-depth tissue penetration of light limits their effectivity for deeply buried tumors. Encouraged by the sonosensitizing ability of the traditional organic photosensitizers, here, we developed AuNPs@Ir1 as a sonosensitizer by hybridizing an organometallic Ir(III) complex (Ir1) with ultrasmall gold nanoparticles (AuNPs) for efficient tumor sonodynamic therapy (SDT) for the first time. AuNPs@Ir1 rapidly entered the cancer cells, produced 1O2, and catalytically oxidized NADH to NAD+ under ultrasound (US) irradiation, thus resulted in cancer cells oncosis. Because of efficient passive retention in tumors post intravenous injection, AuNPs@Ir1 further efficiently inhibited the growth of tumors in-vivo under US stimulation without long-term toxicity to other organs. Overall, this work presents the excellent US triggered in-vitro and in-vivo anticancer profile of the novel AuNPs@Ir1. It is expected to increase the scope of SDT for metal-based anticancer drugs.