Organic Nanomedicine Containing Nonlinear Optical Chromophores for Ultrastable Photo-to-Heat Converting Theranostics in the Near-Infrared Window

Background: Organic agents that are active in the near-infrared (NIR) bio-window for photo-to-heat energy-converting theranostics have attached much attention in cancer therapy. However, current organic NIR-absorbing agents are still suffering from the inefficient non-radiative decay or serious photobleaching under light irradiation. Herein, we design a convenient strategy to load a new kind of NIR-absorbing nonlinear optical (NLO) chromophores with a biocompatible polymer of methoxy poly(ethylene glycol)-poly(lactideco-glycolide) (mPEG-PLGA). Results The resulted NLO/PLGA nanoparticles showed excellent stability, high photothermal conversion efficiency (∼51.11%) and good photoacoustic performance. Moreover, in vitro anticancer experiments demonstrated that the NLO/PLGA nanoparticles possess a high PTT efficiency under NIR laser illumination. Conclusions This work thus provides an insight into the exploration of versatile organic NIR-absorbing nanoparticles toward future practical PTT application.