AN APPROACH TO THE CONSTRUCTION OF AN IMMUNOARRAY FOR DIFFERENTIATINGAND QUANTITATING CROSS-REACTING ANALYTES

We demonstrate the construction of an immunoarray to categorize, ident ify and quantitate different triazine herbicides or their environmenta l metabolites in water. In a first step cluster analysis is used to ex amine the performance of a small subset of antibodies out of a larger library, and hence to select a small array that is capable of categori zing the triazine herbicides into different groups. At the 1 ppb level it is possible to categorize an analyte as a chloro-s-triazine, a hyd roxy metabolite, or as a methoxy/methylthio substituted triazine when using only 2-4 antibodies. At higher concentrations even the identity of the triazine can be determined with the same number of antibodies. A selected combination of antibodies is then used to identify and quan tify unknowns by comparing their immunoassay responses to an array of calibration curves and using the maximum likelihood criterion.