Near-Infrared-Activated Ru(II)-Nile Blue Conjugates as Type-I Photosensitizers for Efficient Hypoxia Tumor Therapy

Abstract

Two cyclometalated Ru(II) complexes functionalized with a modified Nile Blue derivative were developed as near-infrared (NIR)-activated photosensitizers. These complexes efficiently generate superoxide anion radicals (O2˙ˉ) via a type-I mechanism upon irradiation with highly-penetrating 730 nm light, and exhibit outstanding tumor cell-killing efficacy under hypoxic conditions, highlighting their potential for addressing the therapeutic challenges of oxygen-deprived solid tumors.