Temperature-Correlated Afterglow of a Semiconducting Polymer Nanococktail for Imaging-Guided Photothermal Therapy

Nanoparticles for photothermal therapy: Real-time temperature monitoring is critical to reduce the nonspecific damage during photothermal therapy (PTT); however, PTT agents that can emit temperature-related signals are rare and limited to few inorganic nanoparticles. We herein synthesize a semiconducting polymer nanococktail (SPNCT) that can not only convert photo-energy to heat but also emit temperature-correlated luminescence after cessation of light excitation. Such an afterglow luminescence of the SPNCT detects tumors more sensitively than fluorescence as a result of the elimination of tissue autofluorescence, while its temperature-dependent nature allows tumor temperature to be optically monitored under near-infrared (NIR) laser irradiation. Thus, SPNCT represents the first organic optical nanosystem that enables optical-imaging guided PTT without real-time light excitation.