Single nanoparticles as versatile phototheranostics for tri-modal imaging-guided photothermal therapy

Development of versatile phototheranostics is highly desirable for cancer theranostics. Herein, a novel organic conjugated polymer (named DPP-TT) with excellent optical properties was designed and prepared. Based on single-component DPP-TT, single DPP-TT NPs as versatile phototheranostics were developed by a simple nanoprecipitation method. The obtained NPs exhibited good water solubility, excellent biocompatibility, outstanding photostability, strong NIR-I light absorption, and appropriate NIR-II fluorescence emission. Importantly, such NPs presented high photothermal conversion efficiency. From the investigations performed in vitro and in vivo, it was observed that DPP-TT NPs show remarkable performance for cancer theranostics, benefiting from single 808 nm laser-induced tri-modal (NIR-II fluorescence/photoacoustic/thermal) imaging-guided photothermal therapy.