Rapid Analysis of Gyphosate and AMPA in Water Using Fully-Automated Online SPE LC-MS/MS

Oral Presentation

Prepared by T. Anumol, S. Snyder
Agilent Technologies, Inc., 836 N 6th Ave Unit 1, Tucson, AZ, 85705, United States

Contact Information: [email protected]; 412-656-0490


Glyphosate is the most commonly sold herbicide in the world. It is widely detected in US Rivers and surface waters. Recently, concerns have grown that it can have adverse effects on long-term exposure to humans and wildlife. Hence, monitoring of glyphosate along with it’s chief degradation metabolite aminomethylphosphonic acid (AMPA) is an essential requirement for regulatory authorities. Analysis of these compounds has traditionally been performed on GC-MS with an extraction step required to get requisite ng/L sensitivity. This can be laborious, time-consuming and effect reproducibility due to several human intervention steps involved. This study developed a fully automated online solid phase extraction (SPE) method coupled to LC-MS/MS with a derivitization step involving FMOC. Sub 1 ng/L detection limits were achieved with <1 mL of sample injection. Method validation was performed using matrix spike recoveries in multiple matrices, linearity of calibration curves and precision through inter-day and intra-day variability tests. Quantification was performed using isotope dilution method to increase sensitivity and robustness. Retention time locking and multiple transitions also increase specificity of the method. Surface water and ground water samples were analyzed using the method with both compounds detected in select samples.