The Application of Nanozymes in Colorimetric-Electrochemical Dual-Mode Biosensors for Efficient and Advanced Detection: From Mechanism to Applications

The recent developments of analytical methods have brought about far-reaching and remarkable benefits that have positively impacted our lives. This significant and broad influence extends to areas, including medical diagnostics, food safety, and environmental monitoring. Electrochemical techniques are commonly used as efficient sensing approaches due to several advantages such as sensitivity, selectivity, and a wide linear dynamic range. Another high-throughput technique is the colorimetric method which possesses simplicity, affordability, rapid response time, and a high ability to introduce a portable sensing platform. While colorimetric and electrochemical biosensors are widely used as efficient analytical methods, both can be influenced by false results due to instrument error, environmental factors, and interfering substances. The integration of electrochemical and colorimetric techniques into dual-mode biosensors has introduced powerful and high-performance sensing platforms that enable cross-validation and enhance reliability. Particularly, the pivotal role of nanozymes as a bridge to connect in these dual-mode biosensors is undeniable. Nanozymes, with the ability to mimic enzyme activity, have triggered both signals and these nanomaterials stability, in comparison to enzymes, have provided efficient sensing approaches for real-world applications. In this review, we summarize recent advancements of colorimetric-electrochemical dual-mode biosensors based on nanozymes for various applications, including biomarkers, chemical compounds, heavy metals, ions, neurotransmitters, antibiotics, and bacteria detection.