Light‐Activatable Liquid Metal Immunostimulants for Cancer Nanotheranostics

Abstract Gallium‐based liquid metal (LM) nanoparticles are among the most promising nanoscale materials for biomedicinal applications because of their outstanding physicochemical properties, including unique flexibility, easy surface modification, excellent photothermal conversion efficiency, and high biocompatibility. Further exploration of the modification and remote‐controlling performances of LM nanoparticles with functional bioactive molecules for the development of an innovative treatment modality for diseases is challenging. Herein, it is reported that near‐infrared (NIR) light‐activatable LM nanoparticle, which functionalized with immunological activators of T and dendritic cells, can work as highly immunogenic and photo‐exothermic nanoscale stimulants for cancer treatment. The synthesized LM nanostimulant, which has low toxicity, powerful photothermal conversion property, and high immunogenic features, can effectively eliminate cancer cells, cancer spheroids, and colorectal tumors in living mice under NIR laser illumination. Moreover, the fluorescent LM nanostimulant can express strong fluorescence as a reporter agent to identify the targeted tumors in living mice for optical cancer diagnosis. Therefore, such a smart nanostimulant represents a way toward combination photothermal immunotheranostics.