The direct catalytic synthesis of ultrasmall CuO-coordinated carbon nitrides on ceria for multimodal antitumor therapy.

Engineering chem-/sono-/photo-multimodal antitumor therapies has become an efficient strategy to combat malignant tumors. However, the existence of hypoxia in the tumor microenvironment (TME) leads to limited sonodynamic or photodynamic efficiency because O is the key reactant during the process of generation of reactive oxygen species (ROS). Here, to design a desirable platform that can simultaneously convert HO in the TME into ROS and O for efficient chem-/sono-/photo-multimodal tumor therapies, we have created ultrasmall CuO-coordinated carbon nitride on a biocompatible ceria substrate (denoted as CuO-CN@CeO) a self-assisted catalytic growth strategy. The chemical and morphological structures, ROS and O generation activities, and chemo-/photo-/sono-dynamic specificities of CuO-CN@CeO when serving as multifunctional biocatalytic agents were systematically disclosed. The experimental studies validated that CuO-CN@CeO presents state-of-the-art peroxidase-like and catalase-like activities. Moreover, the light excitation and ultrasound irradiation were also demonstrated to boost ROS production. The and experiments suggest that CuO-CN@CeO can efficiently inhibit the growth of malignant melanoma chem-/sono-/photo-multimodal antitumor ability. We believe that applying these new biocatalysts with dual catalytic activities of producing ROS and O will offer a new path for engineering multimodal nanoagents to combat malignant tumors.