Determination of glyphosate and AMPA in oat products for the selection of candidate reference materials

• Published in: Food chemistry Vol. 342; p. 128213
• Main Authors: Cruz, Justine M., Murray, Jacolin A.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 16.04.2021
• Subjects: AMPA; Avena - chemistry; Food Analysis - standards; Glycine - analogs & derivatives; Glycine - analysis; Glycine - isolation & purification; Glyphosate; Liquid chromatography tandem mass spectrometry; Oat-based cereals; Oatmeal; Oats; Organophosphonates - analysis; Organophosphonates - isolation & purification; Reference material; Reference Standards; (Aminomethyl)phosphonic acid-FMOC (PubChem CID: 15339930); Liquid chromatography tandem mass spectrometry; AMPA; Glyphosate-FMOC (PubChem CID: 101243275); Glyphosate-13C2,15N (PubChem CID: 46780452); (Aminomethyl)phosphonic acid (PubChem CID: 14017); Glyphosate; Oatmeal; Oats; Reference material; Oat-based cereals; Glyphosate (PubChem CID: 3496); (Aminomethyl) phosphonic Acid-13C,15N (PubChem CID: 76974379); (Aminomethyl) phosphonic Acid-C,N (PubChem CID: 76974379); Glyphosate-C2,N (PubChem CID: 46780452)
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2020.128213

•A SPE-LC-MS/MS method was validated for the analysis of glyphosate and AMPA in oats.•Glyphosate was detected in all the samples and quantified up to 1100 ng/g.•AMPA was only quantified in 9 samples and mass fractions were lower (<40 ng/g).•Oat products were selected for potential candidate reference materials.•Glyphosate was stable in a ground oat material for six months. The use of reference materials (RMs) is critical for validating and testing the accuracy of analytical protocols. The National Institute of Standards and Technology (NIST) is in initial stages of developing a glyphosate in oats RM. The first aim of this study was to optimize and validate a robust method for the extraction and analysis of glyphosate and aminomethylphosphonic acid (AMPA). The optimized method was used to screen thirteen commercially available oat products to identify candidate RMs. Glyphosate was detected in all samples, with the highest glyphosate mass fraction of 1100 ng/g; lower levels were measured in grains from organic agriculture. AMPA was quantified in nine samples up to 40 ng/g. The findings of this study led to the identification of candidate RMs, with “high” and “low” glyphosate levels. A preliminary stability study determined that glyphosate is stable in oat material at room temperature for six months.