Sequential Diagnosis and Treatment for Colon Cancer via Derived Iridium and Indocyanine Green Hybrid Nanomicelles

Indocyanine green (ICG) has beenwidely explored forthe theranosticsof tumors. However, ICG mainly accumulates in the liver, spleen, orkidney in addition to in tumors, causing inaccurate diagnoses andimpaired therapeutic effects under NIR irradiation. Herein, a hybridnanomicelle was constructed by integrating hypoxia-sensitive iridium(III)and ICG for precise tumor localization and photothermal therapy insequence. In this nanomicelle, the amphiphilic iridium(III) complex(BTPH)(2)Ir(SA-PEG) was synthesized through the coordinationsubstitution of hydrophobic (BTPH)(2)IrCl2 andhydrophilic PEGlyated succinylacetone (SA-PEG). Meanwhile, PEGlyatedICG (ICG-PEG) as a derivative of the photosensitizer ICG was alsosynthesized. (BTPH)(2)Ir(SA-PEG) and ICG-PEG were coassembledby dialysis to form the hybrid nanomicelle M-Ir-ICG. Hypoxia-sensitivefluorescence, ROS generation, and the photothermal effect of M-Ir-ICGwere investigated in vitro and in vivo. The experimental results indicated that M-Ir-ICG nanomicelles couldlocate at the tumor site first and then perform photothermal therapywith 83.90% TIR, demonstrating great potential for clinical applications.

Automated summary

In this study, a hybrid nanomicelle was developed by integrating a hypoxia-sensitive iridium compound and ICG for precise tumor localization and photothermal therapy. The nanomicelle could effectively accumulate at the tumor site and achieve high photothermal therapeutic performance, demonstrating great potential for clinical applications.