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

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 %.