Intercalibration of chromatographic methods in multiresidue pesticide determination

An Ion-Interaction RP-IIR-HPLC method was developed, able to simultaneously separate neutral, basic, and acidic pesticides in a single run. The propos ed method was validated by comparison of the results obtained for the same sample by conventional RP-HPLC and GC/MS methods. For this purpose parametr ic t-, F-, t-paired, and t- for multiple samples and non parametric Wilcoxo n matched-pair signed-rank tests were employed. The accuracy of the propose d IIR-RP-HPLC method was evaluated with respect to a lab-made reference sam ple of spiked tap water.