Immunosensor for trace determination of Irgarol 1051 in seawater using organic media Original Research Article

The development of an immunosensor for the analysis of the s-triazine antifouling agent Irgarol 1051 in organic solvent extracts is presented. The immunosensor was based on the competition between the analyte and an enzyme-labeled analyte analog for the binding sites of a specific antibody. The immunocomplexes are formed in organic solvent–aqueous buffer mixtures and further captured by the immobilized protein A/G. The sensor was able to monitor Irgarol 1051 in methanol (up to 50% v/v) and acetonitrile (up to 25% v/v) extracts at the μg l−1 level, with little interference from other s-triazine compounds. Dertermination of Irgarol 1051 at levels below 1 μg l−1 extracted from surface and seawater samples were performed. The results are similar to those obtained with a previously developed sensor that worked in aqueous buffered media. This new procedure allows the direct determination of Irgarol 1051 using a standard clean-up procedure. Finally, the advantages and drawbacks of organic solvent immunosensing are discussed.