Photothermal‐Switched Single‐Atom Nanozyme Specificity for Pretreatment and Sensing

Abstract Various applications lead to the requirement of nanozymes with either specific activity or multiple enzyme‐like activities. To this end, intelligent nanozymes with freely switching specificity abilities hold great promise to adapt to complicated and changeable practical conditions. Herein, a nitrogen‐doped carbon‐supported copper single‐atom nanozyme (named Cu SA/NC) with switchable specificity is reported. Atomically dispersed active sites endow Cu SA/NC with specific peroxidase‐like activity at room temperature. Furthermore, the intrinsic photothermal conversion ability of Cu SA/NC enables the specificity switch by additional laser irradiation, where photothermal‐induced temperature elevation triggers the expression of oxidase‐like and catalase‐like activity of Cu SA/NC. For further applications in practice, a pretreatment‐and‐sensing integration kit (PSIK) is constructed, where Cu SA/NC can successively achieve sample pretreatment and sensitive detection by switching from multi‐activity mode to specific‐activity mode. This study sets the foundation for nanozymes with switchable specificity and broadens the application scope in point‐of‐care testing.