PREPARATION OF ANTISERA AND DEVELOPMENT OF A DIRECT ENZYME-LINKED-IMMUNOSORBENT-ASSAY FOR THE DETERMINATION OF THE ANTIFOULING AGENT IRGAROL-1051

The development of an immunoassay to determine the antifouling agent I rgarol 1051 o-4-tert-butylamino-6-cyclopropylamino-s-triazine) in seaw ater samples is described. Three polyclonal antisera were obtained by immunizing with a hapten preserving important antigenic determinants s uch as the t-butyl and the methylthio groups of Irgarol. Protein conju gates were characterized by matrix-assisted laser desorption ionizatio n-mass spectrometry (MALDI-MS). Several usable competitive immunoassay s have been obtained by screening a battery of 11 enzyme tracers. The optimized immunoassay presents an I-50 of 0.64 nM (0.163 mu g/l) and a detection limit of 0.062 nM (0.016 mu g/l). Cross-reactivity studies have demonstrated that the immunoassay is specific for Irgarol 1051. O ther triazine compounds are only detected to a minor extent. Performan ce of the immunoassay is not affected by the high salinity content of seawater.