Electrochemical detection of allergen in small-volume whole blood using an array microelectrode: A simple method for detection of allergic reaction

A safe, simplified, and rapid method for detection of allergen has been developed. Serotonin, a chemical mediator secreted during an allergic reaction, was used as a marker in electrochemical detection. A 20‐μL drop of whole blood was used for the electrochemical detection of allergen using an array microelectrode. When cyclic voltammetry was carried out on whole blood samples containing 1 μg/mL serotonin, an anodic peak current appeared at around 350 mV versus a silver/silver chloride electrode using a Nafion‐coated array microelectrode. Allergen was selectively detected using whole blood samples by applying a constant potential of 350 mV after 40 min incubation with addition of allergen. The results obtained by the electrochemical detection method correlated well with the diagnosis obtained from the amount of IgE antibody. © 1999 John Wiley & Sons, Inc. Biotechnol Bioeng 65: 480–484, 1999.