Pushing Boundaries: Introducing Silver-Based Metal–Organic Framework Oxidase-Like Nanozyme over a Wide-Range Temperature

The conventional notion is that enzymes, natural and nanozymes, exhibit peak activity solely within defined psychrophilic or thermophilic conditions. This work challenges the notion by preparing a highly efficient oxidase-mimic of Ag-based metal–organic frameworks (MOFs) (referred to as UoZ-3; UoZ stands for University of Zakho), which work effectively in a wide-range of temperatures. This breakthrough not only widens the working temperature range but also overcomes the instability problem of hydrogen peroxide which limited the use of peroxidase-based applications. UoZ-3 showed lower Michaelis–Menten constants compared to silver nanoparticles and silver ions. Surprisingly, the cold/hot adapted UoZ-3 nanozyme exhibited sensitivity to both hydrogen-atom transfer and single-electron transfer reactions with reducing agents, effectively encompassing all of the antioxidant species that are relevant in physiological contexts. Furthermore, the visual-based platform integrated with a smartphone was established and successfully applied for total antioxidant capacity detection in various temperatures in breast cancer patients. The cold/hot adapted oxidase-mimic nanozyme will open an avenue of nanozyme research and applications.