Studying method of underivatized determination glyphosate, glufosinate and their metabolites in drinking water

Abstract

In Vietnam, glyphosate, one of the most popular herbicides, has recently been prohibited in agriculture due to indiscriminate use and its negative effect on the environment and human's health. Direct analysis and determination glyphosate, glufosinate and their metabolites in environmental samples such as water has get in numerous difficulties due to their simple structure, high polarity and complex formation with different components in the matrices. Therefore, in this research study, we have initially developed a method using ultra‐high performance liquid chromatography (UPLC) coupled with high resolution mass spectrometry with Q‐Orbitrap mass analyzer to analyze anionic compounds such as glyphosate, glufosinate and their metabolites. The use of this system provides low limit of detection (LOD) and quantification (LOQ) of method were 0.003 mg/kg and 0.015 mg/kg, respectively. With respect of sample treatment, we combined C18 and MAX materials in order to obtain the most effective clean up section and high recovery varying from 70 to 120 %.

Chromatographic Methods for the Determination of Glyphosate in Cereals Together with a Discussion of Its Occurrence, Accumulation, Fate, Degradation, and Regulatory Status

“…Despite the higher purchase cost, there are some advantages to a high-resolution instrument compared to a low-resolution one. The ability to work at resolutions of up to 70,000 FWHM (Full Width at Half Maximum) for m/z values of 200 [133,134] allows us to monitor fragments up to four or five decimal places (exact masses). This involves the following: (a) Simplifying sample preparation.…”

“…The retention times were about 8 and 6 min for glyphosate and AMPA, respectively (Figure 10). Other works used the Ion Chromatography-Q-Orbitrap system for monitoring glyphosate and AMPA in honey [140] or UHPLC-Q-Orbitrap with a Torus DEA column to analyze glyphosate and AMPA in drinking water [133]. In this last work, the fragment ions monitored for glyphosate were 168.00620 (precursor), 107.02619 (quantification; MS2, collision energy 25 V), and 133.00546 m/z (confirmation; MS2, collision energy 20 V).…”

“…For AMPA, the following fragments were selected: 110.00043 (precursor), 62.96358 (quantification; MS2, collision energy 25 V), and 80.97415 m/z (confirmation; MS2, collision energy 20 V). Other works used the Ion Chromatography-Q-Orbitrap system for monitoring glyphosate and AMPA in honey [140] or UHPLC-Q-Orbitrap with a Torus DEA column to analyze and AMPA in drinking water [133]. In this last work, the fragment ions monitored for glyphosate were 168.00620 (precursor), 107.02619 (quantification; MS2, collision energy 25 V), and 133.00546 m/z (confirmation; MS2, collision energy 20 V).…”