Nano Research

Article Title

Real-time in vivo visualization of tumor therapy by a near-infrared-II Ag2S quantum dot-based theranostic nanoplatform


in vivo imaging, Ag2S quantum dots, second near-infrared window fluorescence, drug delivery, tumor therapy


Real-time and objective feedback of therapeutic efficacies would be of great value for tumor treatment. Here, we report a smart Ag2S QD-based theranostic nanoplatform (DOX@PEG–Ag2S) obtained by loading the anti-cancer drug doxorubicin (DOX) into polyethylene glycol-coated silver sulfide quantum dots (PEG–Ag2S QDs) through hydrophobic–hydrophobic interactions, which exhibited high drug loading capability (93 wt.% of DOX to Ag2S QDs), long circulation in blood (t1/2 = 10.3 h), and high passive tumor-targeting efficiency (8.9% ID/gram) in living mice where % ID/gram reflects the probe concentration in terms of the percentage of the injected dose (ID) per gram of tissue. After targeting the tumor tissue, DOX from PEG–Ag2S cargoes was selectively and rapidly released into cancer cells, giving rise to a significant tumor inhibition. Owing to the deep tissue penetration and high spatio-temporal resolution of Ag2S QDs fluorescence in the second near-infrared window (NIR-II), the DOX@PEG–Ag2S enabled realtime in vivo reading of the drug targeting process and therapeutic efficacy. We expect that such a novel theranostic nanoplatform, DOX@PEG–Ag2S, with integrated drug delivery, therapy and assessment functionalities, will be highly useful for personalized treatments of tumors.

Graphical Abstract


Tsinghua University Press