Analysis of Glufosinate and Glyphosate in Water by HPLC with Post-Column Derivatization

Poster Presentation

Prepared by R. Smith
Pickering Laboratories, Inc., 1280 Space Park Way, Mountain View, California, 94043, United States

Contact Information: [email protected]; 650-694-6700


Glyphosate is a broad-spectrum herbicide that has been used for several decades to protect a variety of crops. Due to its heavy use in agriculture many weeds have developed resistance
to Glyphosate causing increased interest in finding alternative herbicides. Glufosinate also provides broad-spectrum weed control and can be successfully used against many Glyphosate-resistant plants and grasses. Glufosinate has become increasingly popular creating need for
analytical methods to monitor food and water to ensure protection of human health and environment.

EPA mandates maximum contamination level (MCL) for Glyphosate in water at 700 µg/L. EPA Method 547 describes Glyphosate analysis in drinking water by direct-injection HPLC with post-column derivatization. Glufosinate contains a primary amino group and is also capable of reacting with o-Phthalaldehyde (OPA) reagent. Utilizing mixed-mode analytical column allowed us to develop a simple method capable of separating Glufosinate and Glyphosate in water with direct injection. This method eliminates complicated and labor-intensive sample pretreatment
steps, required by LC/MS analysis. Post-column derivatization with OPA reagent ensures high sensitivity of analysis without matrix interferences or signal suppression.