Advances in the alkylsilyl derivatization of glyphosate and aminomethylphosphonic acid: A critical comeback to the N-tert.-butyldimethylsilyl-N-methyltrifluoroacetamide reagent

Practical utility of the MTBSTFA/PYR method was confirmed by the analysis of the AMPA impurities in GLYP market samples, expressed as g/L AMPA: GlialkaR Star, 6.45 g/L (5.1 RSD%); FozátR, 6.89 g/L (4.34 RSD%); Medallon P, 7.15 g/L(4.28 RSD%) and Total Spray, 0.038 g/L (4.64 RSD%).