A TURN-KEY GUARANTEED ANALYSER FOR THE ROUTINE MEASUREMENT OF GLYPHOSATE AND AMPA IN DRINKING WATER (EUROPEAN DRINKING WATER DIRECTIVE 98/83/EC) AND OTHER ENVIRONMENTAL WATER SAMPLES

Importance of the Topic

The routine measurement of glyphosate and its main metabolite AMPA in drinking water is critical to meet regulatory limits and address rising environmental and health concerns. Glyphosate is one of the most extensively used herbicides worldwide, and its persistence in aquatic systems requires reliable, sensitive analytical methods to ensure compliance with the European Drinking Water Directive and to protect public health.

Objectives and Study Overview

This work presents a complete, turn-key analytical solution for the trace determination of glyphosate and AMPA in potable, borehole and surface water. The goals were to develop a validated, robust workflow delivering limits of detection below 10 ng/L, to streamline sample preparation via derivatization and online enrichment, and to provide laboratories with a ready-to-operate system including instrumentation, methods and training.

Methodology and Instrumentation

A combined approach is employed: offline derivatization of samples with FMOC-Cl reagent, followed by online solid-phase extraction (SPE) enrichment and separation on an Agilent 1200 Series HPLC coupled to a 6460 triple quadrupole mass spectrometer (LC/QQQ) with negative-ion electrospray. Key steps include:

• Derivatization: Samples are treated with EDTA, borate buffer and FMOC-Cl, heated at 100 °C and held overnight to form FMOC derivatives.
• Online Enrichment: A 900 µL aliquot of derivatized water is loaded onto an SPE cartridge in the autosampler, then backflushed onto a C18 analytical column.
• Chromatography and Detection: Separation on a 2.1×150 mm, 3.5 µm C18 column at 60 °C with a water/acetonitrile gradient, followed by MRM acquisition on the 6460 QQQ.

Instrumentation

The system comprises:

• Agilent 1200 Series HPLC: Quaternary and binary pumps, autosampler with extended injection volume, column compartment.
• Agilent 6460 Triple Quadrupole MS: Jet Stream interface for enhanced sensitivity, with optimized gas and voltage settings.

Main Results and Discussion

The method achieves limits of detection below 0.01 µg/L for both analytes and linear calibration over the 0.01–0.50 µg/L range. Recovery studies at 0.1 µg/L in tap, borehole and river waters yielded recoveries between 98 % and 102 %. Repeatability, assessed according to ISO/TS 13530:2009 at 0.01, 0.10 and 0.50 µg/L, showed relative standard deviations below 3.6 %. A full analytical cycle for 20 samples plus controls can be completed within 24 hours, demonstrating suitability for routine monitoring.

Benefits and Practical Applications

• The derivatization and online enrichment approach protects the analytical column from buffer components and yields high sensitivity without extensive manual extraction.
• Internal standards compensate for matrix effects in diverse water types.
• The package includes validated SOPs, consumables and on-site training to accelerate method implementation.

Future Trends and Applications

Advancements may include further miniaturization of SPE cartridges, integration with automated sample robots, and expansion to other polar organic contaminants. Adaptation of the workflow to field-deployable systems or high-throughput environmental monitoring platforms could enhance real-time water quality surveillance.

Conclusion

The Agilent turn-key LC/QQQ solution offers a fully validated, sensitive and robust method for routine glyphosate and AMPA analysis in drinking and environmental waters. By combining offline derivatization with automated online enrichment and triple quadrupole detection, laboratories can reliably meet stringent regulatory requirements and address emerging analytical challenges.

References

1. European Drinking Water Directive 98/83/EC.
2. ISO/TS 13530:2009, Water Quality — Method Validation.
3. Agilent Technologies, Application Note 5991-3276EN, “Turn-key Analyser for Glyphosate and AMPA in Drinking Water”, 2013.