A diketopyrrolopyrrole-based conjugated polymer for efficient photodynamic and photothermal combination therapy under single 808 nm laser irradiation

Photodynamic therapy (PDT) and photothermal therapy (PTT) are two powerful tools to tackle cancer in the biomedical field due to their super tumor ablation efficiency and minimal damage to normal tissue. However, it is still a tricky challenge to combine these two treatment modalities into a single agent for single wavelength laser triggered efficient tumor therapy. Herein, water-soluble nanoparticles consisting of diketopyrrolopyrrole-based conjugated polymer and amphipathic Pluronic F127 were intelligently devised and fabricated, which possessed outstanding optical properties, superb biocompatibility, excellent photostability. Surprisingly, the nanoparticles exhibited moderate singlet oxygen yield (2.34%) and photothermal conversion efficiency (41.5%) under an 808 nm laser illumination, which was in favor of achieving high-performance PDT/PTT combination therapy. Moreover, the evident antitumor effect of the nanoparticles was confirmed by in vitro and in vivo experiments. This work provides a promising approach to rationally design near infrared absorbing organic polymer nanoplatforms for combination cancer therapy.