Method for determination of glyphosate residues in natural waters based on polarography of the N-nitroso derivative
Abstract
A differential pulse polarographic method for the determination of residues of glyphosate herbicide in natural waters down to 35 µg l–1 is described. The material is concentrated by chromatography on an anion-exchange column, which at the same time serves as the only clean-up step required. A polarographically active glyphosate derivative is obtained by nitrosation performed directly in a fraction of the eluate from the column. The precision in terms of relative standard deviation varies from 22.8% at the detection limit to 2.3% at 210 µg l–1. The total analysis time for one sample is 3–4 h.