Progress in Electrochemical Immunosensors with Alkaline Phosphatase as the Signal Label

Abstract

Electrochemical immunosensors have shown great potential in clinical diagnosis, food safety, environmental protection, and other fields. The feasible and innovative combination of enzyme catalysis and other signal-amplified elements has yielded exciting progress in the development of electrochemical immunosensors. Alkaline phosphatase (ALP) is one of the most popularly used enzyme reporters in bioassays. It has been widely utilized to design electrochemical immunosensors owing to its significant advantages (e.g., high catalytic activity, high turnover number, and excellent substrate specificity). In this work, we summarized the achievements of electrochemical immunosensors with ALP as the signal reporter. We mainly focused on detection principles and signal amplification strategies and briefly discussed the challenges regarding how to further improve the performance of ALP-based immunoassays.

Overview on the Development of Electrochemical Immunosensors by the Signal Amplification of Enzyme- or Nanozyme-Based Catalysis Plus Redox Cycling

“…Nonetheless, the low sensitivity of traditional electrochemical immunoassays cannot meet the need of the ultrasensitive determination of trace analytes [ 5 ]. In order to fulfill the urgent requirement of immunosensors with a high sensitivity and low detection limit, various signal amplification strategies have been integrated with immunoassays in the past decades [ 6 , 7 ], including enzymatic catalysis [ 8 ], DNA-based amplification techniques [ 9 , 10 ], and functional nanomaterials [ 11 , 12 , 13 , 14 , 15 , 16 ]. Among them, the perfect integration of the high specificity of enzymatic catalysis with the high simplicity of electrochemical techniques has become a successful approach for designing novel immunosensors in disease diagnosis, medicine research, and environmental monitoring [ 17 , 18 , 19 , 20 ].…”