Desenvolvimento de método para análise de 2,4-D em águas

Abstract

The State of Mato Grosso has been highlighted in the production of cotton, soybean and corn crops with great economic impact for the country. However, the high levels of production require large amounts of pesticides, which can be toxic not only to the organism target, but also for the environment. Among the pesticides used, 2,4-dichlorophenoxyacetic acid (2,4-D) stands out as the second most used in Brazil, due to its low cost, high efficiency and good solubility in water. This analyte can be found in environmental matrices at the trace level, making it necessary to use pre-concentration analytical methods for its determination in water bodies. In the present work, a method was developed and validated for the determination of the pesticide 2,4-D, in mili-Q fortified water, by UHPLC-MS/MS using solid phase extraction for extraction and pre-concentration of the analyte. The analytical curve obtained showed linearity in the concentration range of 0.4 to 1.2 μg L-1 , with a correlation coefficient of 0.999049, the method presented an instrumental detection limit (LDi) and instrumental quantification limit (LQi) of 0.062 μg L-1 and 1.9 μg L-1 , respectively. The evaluation of the method's accuracy, through the addition and recovery test, showed satisfactory recovery results, with these being between 40 and 120% for concentrations of 0.25, 0.5 1 μg L-1 . Considering the pre-concentration factor of 500 times, the detection and quantification limits of the method were 0,124 ng L-1 e 0,38 ng L 1 , respectively. Given the above, the method proves to be adequate for the analysis of 2,4-D in milli-Q fortified water.