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Solid-Phase Electrochemical Enzyme Immunoassay With Attomole Detection Limit By Flow Injection Analysis, Yan Xu, H. Brian Halsall, William R. Heineman

Chemistry Faculty Publications

A sandwich electrochemical enzyme immunoassay with flow injection analysis for the model antigen mouse IgG has been developed with alkaline phosphatase as the enzyme label. The enzyme substrate, 4-aminophenyl phosphate and its enzymatic reaction product, 4-aminophenol have been studied by cyclic and hydrodynamic voltammetry. The determination of 4-aminophenol by flow injection analysis with electrochemical detection (FIAEC) has a linear range of 5.0 × 10−8 to 1.0 × 10−5 M, a detection limit of 2.4 × 10−8 M, and a sample throughput of 72 samples/h. The detection limit is set by a background capacitance response, which depends on the ionic strength …