Surface Plasmon Resonance-Enhanced Photoacoustic Imaging and Photothermal Therapy of Endogenous H2S-Triggered Au@Cu2O

Smart theranostics agents triggered by endogenous H2S with combined activated photoacoustic imaging and photothermal therapy can improve the diagnosis and treatment of colon cancer. However, the low theranostic performance of the current smart theranostics agents after the triggering step has limited their further application. In this work, the theranostic performance of endogenous H2S-triggered Au@Cu2O for the diagnosis and treatment of colon cancer, which is generated from the localized surface plasmon resonance coupling effect between a noble metal (Au) and a semiconductor (Cu2O), is investigated. Compared with Cu2O, the prepared H2S-triggered Au@Cu2O shows a significantly stronger absorption at the near-infrared region, such as a approximate to 2.1 times change at 808 nm, giving a photothermal conversion efficiency increase of approximate to 1.2 times. More importantly, Au@Cu2O still exhibits good photoacoustic imaging contrast and photothermal properties for treatment of colon cancer in vivo even at very low injection doses. This work not only investigates an endogenous H2S-triggered Au@Cu2O theranostic agent with enhanced theranostic performance for colon cancer but also provides a novel strategy for designing high-performance theranostic agents.