Analysis of Pesticide Degradation Products by Tandem High-Performance Immunoaffinity Chromatography and Reversed-Phase Liquid Chromatography

The analysis of pesticide degradation in environmental samples is often difficult to perform due to the different polarities and lower concentrations of the degradation products versus the parent compound. This work examines the use of tandem high-performance immunoaffinity chromatography (HPIAC) and reversed-phase liquid chromatography (RPLC) for measuring degradation products of the herbicide atrazine in water at levels in the low nanogram per liter, or parts-per-trillion, range. An HPIAC column containing anti-triazine antibodies was first used to extract the degradation products of interest from samples, followed by the on-line separation of the retained components on a C18 RPLC analytical column. The final system had a total analysis time of 35 min for a 13 mL sample injection and gave good correlation versus GC/MS. The limits of detection for hydroxyatrazine, deethylatrazine, and deisopropylatrazine were 20−30 ng/L for 13 mL samples and 6−10 ng/L for 45 mL samples. The use of this method was demonstrated in the analysis of both river water and groundwater samples. By changing the HPIAC column and reversed-phase separation conditions, the same approach could be modified for the detection of other pesticides and their degradation products.