Metal-organic framework nanozymes as next-generation biosensing platforms: from catalytic design to point-of-care detection in real-world samples.

Metal-organic frameworks (MOFs) have emerged as a transformative class of nanozymes, offering unprecedented tunability in catalytic activity, structural porosity, and surface functionality for biosensing applications. This review traces the evolution of MOF nanozymes from their foundational design principles to their integration into advanced point-of-care (POC) diagnostic devices. It further examines the structural and mechanistic basis of enzyme-mimicking behavior in MOFs-encompassing peroxidase-, oxidase-, catalase-, and superoxide dismutase-like activities-alongside signal transduction strategies including colorimetric, fluorescent, electrochemical, photoelectrochemical, and multimodal approaches. Real-sample applications spanning human biofluids, food matrices, and environmental samples are surveyed, with emphasis on how metal doping, defect modulation, heterostructure assembly, and host-guest encapsulation enable MOF nanozymes to overcome matrix interference. The integration of MOF nanozymes into portable paper-based, wearable, and smartphone-assisted platforms is also discussed, along with key challenges and future directions for translating these advances into deployable diagnostic tools.