Abstract:Magnetic microbeads, which possess a huge specific surface area and high dispersion capability, can capture biomolecules and form stable immune complexes that can be rapidly separated as a result of the superparamagnetism of the magnetic microbeads. The sample pretreatment is simple, and the target compounds can be rapidly detected without complex pretreatment steps such as pre-concentration or purification. Moreover, because the electrochemical analysis technique is ultrasensitive, its coupling with magnetic microbeads provides a novel detection system. In recent years, active research programs have been undertaken in this field and important progress has been achieved. Miniaturized electrochemical immunoassay systems with high sensitivity, rapid detection, and simple operation have been developed and can be used in food analysis, environmental evaluation, clinical diagnostics, etc. In this review, the most recent research progresses in electrochemical immunoassay technology using magnetic microbeads as a solid phase are summarized, especially in terms of immunoassays using magnetic electrodes, immunoassays in a droplet using a rotating disk electrode, and magnetic-microbead-based immunoassays using enzyme labels and nanoparticle tags. Additionally, the future work in this field is discussed.
