Crystalline Copper Hydroxide Nanosheets with KatG-like Dual Activities for Synergized Nanocatalytic Tumor Therapy.

Abstract

The enzyme-mimicking catalytic activities of inorganic nanomaterials have attracted broad attention recently. Catalase-peroxidase (KatG) is a bifunctional enzyme with both catalase and peroxidase activities that converts hydrogen peroxide (H₂O₂) into both oxygen (O₂) and a radical, respectively. Herein, crystalline Cu(OH)₂ nanosheets have been synthesized and demonstrated as inorganic nanocatalysts with KatG-like activity for nanocatalytic tumor therapy. The distinct crystalline structure of the Cu(OH)₂ nanosheets features abundant bis(μ-hydroxo)Cu^IICu^II dinuclear catalytically active sites, enabling efficient redox cycling to favor one two-electron transfer for O₂ generation (catalatic catalysis) and two consecutive single-electron transfers for hydroxyl radical (^•OH) generation (peroxidatic catalysis), successively. During tumor therapy, the O₂ generation by the nanomaterial mitigates intratumoral hypoxia and sensitizes cancer cells to oxidative attack, resulting in significantly enhanced anticancer efficacy. This work bridges dual-active nanocatalysis with bifunctional enzymatic catalysis, presenting a crystalline inorganic nanomaterial with KatG-like activity and its synergy for nanocatalytic tumor therapy.