Stimuli-Responsive Hybrid Vesicle for Tumor Dual-Model NIR-II Photoacoustic and Fluorescence Imaging and Precise Radiotherapy

摘要

Bioimaging guided-radiotherapy is widely investigated as one of the mainstreamcancer theranostic strategies for precision medicine. Nevertheless,background noise with “always-on” imaging signal and inadequate tumorenrichment restrict disease diagnosis and therapy. Here, a nanogapped goldnanoparticles (AuNNPs)–silver sulfide (Ag_2S) vesicle (Ve) is designed as a“biological switch” through the self-assembly of pH-responsive polymerthiolated polystyrene-co-poly(4-vinylpyridine) grafted AuNNPs and Ag_2Squantum dots (QDs). The AuNNPs–Ag_2S Ve exhibits quenched NIR-IIfluorescence (FL) and enhanced photoacoustic signals initially, which can bespecifically activated by an acidic environment to release Ag2S QDs and “turnon” NIR-II FL signal in the second near-infrared (NIR-II, 950–1700 nm)window. Besides, the strategy of disease-located NIR-II imaging guidedcancer therapy can remarkably enhance the therapeutic efficacy of radiotherapy,as well as minimize side effects. Such an intelligent nanoplatformwith the ability of stimulus activated NIR-II imaging guided radiotherapyshows great promise to precision biomedicine in the future.