Immunosensor for human IgE detection using electrochemical redox cycling with ferrocene‐mixed self‐assembled monolayers modified Au electrode

Abstract

The concentration of human immunoglobulin E (IgE) in blood is an indicator for diagnosing an allergy. For detecting human IgE by an electrochemical immunosensor, redox mediator molecules were modified on a gold electrode using thiolated organic molecules, which can form self-assembled monolayers on the electrode surface. Ferrocene was used as a redox mediator, and the current signal was amplified via redox cycling using 4-aminophenol. Measurements were obtained after the immobilization of the target-captured antibody, target human IgE, biotin-conjugated secondary antibody, and avidin alkaline phosphatase in a sandwich-type immunosensor configuration. The prepared immunosensor exhibited a limit of detection of 1 IU/mL and dynamic range of 3-30 IU/mL. K E Y W O R D S electrocatalytic reaction, electrochemical biosensor, ferrocene, gold (Au) electrode, human immunoglobulin E

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