A Dilute-and-Shoot LC–MS/MS Method for Urinary Glyphosate and AMPA

A method for the simultaneous determination of glyphosate and aminomethylphosphonic acid (AMPA) in urine was developed using a “dilute-and-shoot” sample preparation. A 1:1 dilution of urine sample in 15 mmol L−1 heptafluorobutyric acid (HFBA) was prepared prior to being injected into the LC–MS/MS system. The chromatographic separation was achieved by a Gemini C6-Phenyl analytical column, with the gradient elution of 15 mmol L−1 HFBA in water and acetonitrile. The limits of detection and quantitation of both compounds were 2.5 ng mL−1 and 5 ng mL−1, respectively. The sample preparation time was achieved in 2 min using only 0.1 mL of urine sample. The validated method was successfully applied to glyphosate and AMPA determination in farmer urine samples.