Avaliação de monolitos poliméricos como fases extratoras para herbicidas triazínicos

Abstract

The solid phase extraction (SPE) is one of the most used techniques for the extraction and / or pre-concentration of analytes in food and environmental matrices. It has a number of benefits compared to classical methods, such as greater convenience, sensitivity and low use of organic solvents. In SPE, sorbents (solid material) are used as fillings for cartridges as syringe and one of the largest applications is for the analysis of agrochemicals. The intensive use of pesticides creates several problems, the herbicide behavior knowledge is essential in the evaluation of its effectiveness in agriculture and understanding of the environmental impact caused by them. The use of monolithic materials as stationary phase in chromatographic separations is reported since 2000. The monolithic materials provide greater surface area than packed particles, hence higher extraction capacity per mass unit, with cartridges that have been produced with less of adsorbent material to result in less solvent use and increased sensitivity. The analysis by HPLC (High Performance Liquid Chromatography) were performed in two stages: analysis of standards for the determination of retention times and herbicides calibration curves (Atrazine and Prometryn), and analysis of artificial samples after extraction of it via SPE. The values of the correlation coefficients (R2) obtained from 0.94033 for prometryn, and 0.99605 for atrazine, indicates that the range of concentrations studied shows a good linearity. The monolithic sty-DVB copolymer (styrene-divinylbenzene) was synthesized via in situ bulk polymerization. The sty-DVB polymer has good potential as extraction phase for the studied herbicides, and the method of analysis by liquid chromatography high performance sensitive and suitable for the analytes tested.