Fluorescent nanozymes: Emerging versatile materials advancing analytical chemistry

Since the revelation of Fe₃O₄ nanoparticles with enzyme-like characteristics, nanozymes present a promising alternative to traditional bio-enzymes due to their straightforward preparation, good robustness, and adjustable performance. In addition to enzyme-mimetic catalysis, these materials also tend to show optical, electrical, thermal, and magnetic properties. Integrating nanozyme catalysis with these properties into an entity can offer fascinating merits to biochemical sensing. Especially, fluorescent nanozymes, a class of materials combining enzyme-mimicking activity and fluorescence, have been drawing growing interest in the analytical chemistry community in the past five years. To highlight the achievements and progress made in this emerging area, here we, for the first time, present a comprehensive summary on fluorescent nanozymes and their roles in advancing analytical detection. First, a definition of fluorescent nanozymes is given, and their bifunctional features are discussed. Then, common strategies employed to develop different material types of fluorescent nanozymes are introduced. Emphatically, their unique contributions to biochemical analysis are clarified in detail, along with various applications in environmental monitoring, food safety analysis, and biomedical detection. Finally, substantial potential of fluorescent nanozymes in realizing advanced detection as well as existing challenges is spotlighted. Our review provides a comprehensive and up-to-date reference on fluorescent nanozymes, which will attract more attention and guide future efforts to further promote the promising field.