Near-Infrared-Absorbing Conjugated Polymer Nanoparticles Loaded with Doxorubicin for Combinatorial Photothermal-Chemotherapy of Cancer

Combination therapy based on a nanoscale drug delivery system (nDDS) shows great promise in cancer therapy. We report herein the development of a nanotherapeutic that combines photothermal therapy (PTT) and chemotherapy into one nanoformula to achieve combinatorial anticancer capacity. Near-infrared (NIR)-absorbing conjugated polymers (CPs) were used as the PTT agents and coloaded with chemotherapeutic drug doxorubicin (Dox) to afford the multifunctional delivery system DCP NPs. The strong NIR absorbance of CPs endows DCP NPs with excellent photothermal capacity and NIR laser triggered drug release property. The fluorescence of Dox was quenched after encapsulation because of the fluorescence resonance energy transfer (FRET) effect between Dox and CPs, which could be used to monitor the intracellular Dox release from DCP NPs. As a result of these properties, DCP NPs exhibited very potent anticancer capacity against osteosarcoma 143B cells. This study demonstrates the great potential of CPs-based nanotherapeutic for combined photothermal-chemotherapy to combat cancer.