SIMULTANEOUS DETERMINATION OF SEVERAL PESTICIDES WITH CHEMILUMINESCENT IMMUNOASSAY ON A MULTI-SPOT MEMBRANE STRIP

Chemiluminescent immunoassay with two types of a multispot membrane st rip has been developed for the simultaneous determination of several p esticides in water samples. Three types of antibodies with different c ross-reactivity towards s-triazines were immobilized in three separate spots of the first strip (called a 'triazine membrane strip') by mean s of a photoimmobilization technique. The second strip (called a 'pest icide membrane strip') contained two pesticide-specific spots with imm obilized antibodies, one specific to 2,4-dichlorophenoxyacetic acid an d another with a high extent of cross-reactivity toward different s-tr iazines. Each membrane strip contained two additional spots. One was e mployed as a positive control or cut-off spot, and the other one was u sed to check the background luminescence. The immunoassay with a multi spot membrane strip allowed us to estimate semi-quantitatively the con centration for a particular analyte by a comparison of the recorded li ght intensifies of the analyte spot and the cut-off spot. The applicat ion of the triazine membrane strip provides a differentiation between atrazine, simazine and terbuthylazine in mixtures, and the pesticide m embrane strip allows the performance of group-specific assays.