Anchoring Ru Single-Atom on MXene Achieves Dual-Enzyme Activities for Mild Photothermal Augmented Nanocatalytic Therapy

Abstract

Single-atom catalysts with abnormally catalytic active sites have garnered extensive attention and interest for their application in tumor therapy. However, despite the advancements made with current nanotherapeutic agents, efficient systems for triggering cancer treatment remain challenging, due to their low activity, uncontrollable behavior, and nonselective interactions. Herein, we construct Ru single-atom anchored MXene nanozymes (Ru-Ti3C2Tx-PEG) with mild photothermal effect and multi-enzyme catalytic activity for synergistic tumor therapy. The Ru single-atom is anchored on the surface of MXene nanosheets, which not only facilitates multi-enzyme catalytic activity, but also amplifies the photothermal performance owing to the localized surface plasmon resonance effect. The Ru single-atom could decompose H2O2 into toxic hydroxyl radical (•OH) in response to tumor microenvironment (TME) for enzyme catalytic therapy, and the heat produced by nanozymes upon near-infrared laser excitation can enhance the •OH generation yield. Also, the nanozymes have oxygen formation and glutathione depletion capability in cancer cells, regulating the TME and accelerating the •OH levels. The in vitro and in vivo research confirms that the two-dimensional Ru single-atom anchored MXene nanozymes have extraordinary tumor growth inhibition effect, presenting a rational therapeutic strategy for tumor ablation through the synergistic photothermal and heat-promoted enzymatic catalysis.