Pushing Boundaries:\nIntroducing Silver-Based Metal–Organic\nFramework Oxidase-Like Nanozyme over a Wide-Range Temperature

The conventional notion is that enzymes, natural and\nnanozymes,\nexhibit peak activity solely within defined psychrophilic or thermophilic\nconditions. This work challenges the notion by preparing a highly\nefficient oxidase-mimic of Ag-based metal–organic frameworks\n(MOFs) (referred to as <b>UoZ-3</b>; UoZ stands for University\nof Zakho), which work effectively in a wide-range of temperatures.\nThis breakthrough not only widens the working temperature range but\nalso overcomes the instability problem of hydrogen peroxide which\nlimited the use of peroxidase-based applications. <b>UoZ-3</b> showed lower Michaelis–Menten constants compared to silver\nnanoparticles and silver ions. Surprisingly, the cold/hot adapted <b>UoZ-3</b> nanozyme exhibited sensitivity to both hydrogen-atom\ntransfer and single-electron transfer reactions with reducing agents,\neffectively encompassing all of the antioxidant species that are relevant\nin physiological contexts. Furthermore, the visual-based platform\nintegrated with a smartphone was established and successfully applied\nfor total antioxidant capacity detection in various temperatures in\nbreast cancer patients. The cold/hot adapted oxidase-mimic nanozyme\nwill open an avenue of nanozyme research and applications.