A novel fluorimetric method for glyphosate and AMPA determination with NBD-Cl and MCR-ALS

PÉREZ, ANA L.; TIBALDO, GIULIANA; SÁNCHEZ, GERMÁN H.; SIANO, GABRIEL G.; MARSILI, NILDA R.; SCHENONE, AGUSTINA V.

SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY.

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2019 vol. 214 p. 119 - 128

1386-1425

We report the development of a new analytical method for the quantification ofN-(phosphonomethyl)glycine (glyphosate) and (aminomethyl)phosphonic acid (AMPA)by combining spectrofluorimetry and multivariate calibration. In this study,fluorescence spectroscopy was used to quantify glyphosate and AMPA, which werepreviously derivatized with the fluorogenic reagent: 4-chloro-7-nitrobenzofurazan(NBD-Cl). Fluorescence excitation-emission matrices (EEM) were recorded by excitingbetween 400 and 500 nm, and measuring the emission between 500 and 610 nm. Thesecond-order data obtained were processed using the Multivariate Curve Resolutionwith Alternating Least Square (MCR-ALS) methodology. The developed method wasused to predict different concentrations of glyphosate and AMPA in validation samples.In addition, the presence of the herbicide was evaluated in real samples: a commercialformulation and a water sample from a cultivated area. For this purpose, the standardaddition method was used to study the matrix effect in each case. The ranges of workingconcentrations obtained for this new method are in agreement with the amounts foundin surface water samples near a direct sowing soybean growing region in Argentina.