Hydrogen Sulfide Dual-Activated NIR-II Photoacoustic Probes for Accurate Imaging and Efficient Photothermal Therapy of Colon Cancer
Shulong Wang, Liangliang Zhang, Jingjin Zhao, Li Hou, Changchun Wen, Hong Liang, Shulin Zhao
Abstract
Hydrogen sulfide (H2S) content has been shown to be significantly increased in colon cancer tissue; imaging H2S in vivo enables the accurate diagnosis of colon cancer disease. Photoacoustic (PA) imaging is a biological imaging mode combining photoexcitation and ultrasonic detection, and high-resolution imaging in deep biological tissues can be achieved using PA probes in the second near-infrared biowindow (NIR-II). Nevertheless, existing materials can only be used as contrast agents to achieve the PA imaging of biomolecules in NIR-II, which still remains a challenge. To this end, water-soluble MoO3 nanoparticles were prepared, and it was found that PA imaging and photothermal therapy (PTT) of colon cancer tissue can be specifically activated in NIR-II by endogenous H2S. Therefore, MoO3 nanoparticles were used as an NIR-II nanoprobe for PA imaging and PTT of colon cancer tissue. Furthermore, by comparing the efficiency for the PA imaging and PTT of colon cancer in NIR-I and NIR-II, it was proven that in the NIR-II window, the background interference of the PA imaging for biological tissue was low, the photothermal efficiency was high, and the PTT effect was good. This work developed a specific nanoprobe that was used for PA imaging of bioactive small molecules in NIR-II, providing an approach for the diagnosis and treatment of colon cancer.