Photovoltaic Molecule-Based Phototheranostics With A-D-A Structure for Near-Infrared Fluorescence Imaging-Guided Synergetic Photodynamic and Photothermal Therapy of Tumors.

Phototheranostics with near-infrared fluorescence and reactive oxygen species generation ability and high photothermal conversion efficiency (PCE) plays a significant role in fluorescence imaging-guided synergetic photodynamic and photothermal therapy of tumors. Here, a star molecule in organic photovoltaic materials, NCBDT-4C with an A-D-A conjugated structure, was assembled with DSPE-PEG-NH2 to prepare water dispersive nanoparticles (NPs). The prepared NCBDT-4Cl NPs exhibited a maximum NIR absorption peak at 764 nm and a maximum fluorescence peak at 798 nm. These NPs could generate superoxide anion, singlet oxygen (1O2), and heat under 808 nm laser irradiation. The 1O2 generation quantum yield and PCE of the NPs were 37.5% and 53.6%, respectively. The combination of photodynamic and photothermal therapy of cancer was demonstrated in vitro and in vivo. This work presents the advanced application of organic photovoltaic materials in cancer phototherapy.