enzyme-mimic nanoparticles-based photonic methods for the detection of biological molecules

Inorganic nanoparticles with enzyme-mimicking ability (nanozymes) have gained ‎significant attention in the fields of analytical sensing, biosensing, and nanomedicine. ‎nanozymes exhibit several advantages over natural enzymes due to their high stability ‎against protease digestion or denaturation, structural, morphological, and functional integrity ‎under different environmental stress (low ph, high temperature or the presence of salt), ‎inexpensive preparation, and wide application as electrocatalysts. in recent years, various ‎nanozymes with peroxidase-like activity (e.g., peroxidase, oxidase, and catalase) have been ‎employed for: (a) determination of h2o2, (b) glucose detection in biological (blood and ‎urine) samples, (c) evaluation of antioxidants and (d) nanozyme-based colourimetric and ‎electrochemical immunosensors and nucleic acid sensors. ‎sensitive detection of biological signals is of great importance for the early diagnosis ‎and treatment of diseases. the prosperous development of optical and photonic ‎technologies in recent years provides many choices for optical detection of biological ‎signals in complex biological structures. optical detection exploits optical responses, such as ‎light absorption, scattering, fluorescence, and reflectance, induced by ‎biophysical/biochemical changes for bioidentification and disease diagnosis. ‎one of the most important areas of research for nanozymes is the evaluation of various ‎biomolecules in biological samples. in this regard, chemiluminescence (cl) and ‎fluorescence (fl) methods are appropriate detection systems for analytical purposes owing ‎to their favorable characteristics including economical instrumentation, rapidity, simplicity, ‎considerable sensitivity, and lower detection limits. the measurement of various ‎biomolecules (such as glucose, h2o2, different drugs and etc.) using the enzymatic activity ‎of nanoparticles, as well as fluorescence and chemoluminescence approaches, has been ‎reported in several studies. besides, nanomaterials have been recently introduced as ‎effective catalysts in the cl and fl processes, mainly to improve the cl and fl emission. ‎as a result, researchers have focused their attention on creating sensitive and selective ‎nanomaterial-based optical techniques for the detection of biological macromolecules in ‎real samples.‎