Nanozyme-based electrochemical biosensors for disease biomarker detection.

In recent years, a new group of nanomaterials named as nanozymes that exhibit enzyme-mimic catalytic activity, has emerged as a promising alternative to natural enzymes. Nanozymes can address some of the intrinsic limitations of natural enzymes such as high cost, low stability, difficulty in storage, and specific working conditions (i.e., narrow substrate, temperature and pH ranges). Thus, synthesis and applications of hybrid and stimuli-responsive advanced nanozymes could revolutionize the current practice in life sciences and biosensor applications. On the other hand, electrochemical biosensors have long been used as an efficient way for quantitative detection of analytes (biomarkers) of interest. As such, the use of nanozymes in electrochemical biosensor is particularly important to achieve low cost and stable biosensors for prognostics, diagnostics, and therapeutic monitoring of diseases. Herein, we summarize the recent advances in the synthesis and characterization of common nanozymes and their application in electrochemical biosensor development. After briefly overviewing the applications of nanozymes in non-electrochemical-based biomolecular sensing systems, we thoroughly discuss the state-of-the-art advances in nanozyme-based electrochemical biosensors, including genosensor, immunosensor, cytosensor and aptasensor. The applications of nanozymes in microfluidic-based assays are also discussed separately. We also highlight the challenges of nanozymes-based electrochemical biosensors and provide some possible strategies to address these limitations. Finally, future perspectives on the development of nanozymes-based electrochemical biosensors for disease biomarker detection are presented. We envisage that standardization of nanozyme and their fabrication process may bring a paradigm shift in biomolecular sensing by fabricating highly specific, multi-enzyme mimicking nanozymes for the highly sensitive, selective, and low-biofouling electrochemical biosensor.