Development of analytical methodologies for the determination of chlorpyryphes in aqueous samples employing the dispersive liquid microextraction followed by HPLC-UV.

Abstract

The miniaturized extraction techniques use less aggressive methods to the environment, since they generate less waste and spend a minimum of organic solvents, besides having a good selectivity and specificity in the extractions. In this context, liquid-liquid dispersive microextraction (DLLME) has been highlighting. Thus, the present article describes an optimization of the DLLME using low environmental impact extractor solvent to determine the chlorpyrifos insecticide in water. The analytical curves presented values for the correlation coefficient (r) higher than 0.999. The limits of detection and quantification were 0.24 and 0.80 μg L-1, respectively. There were recoveries between 93 and 97 %, with relative standard deviation (RSD) varying between 1.00 and 3.61%. The developed methods presented accurate and reliable results, are simple and safe, characteristics important for the implementation of a methodology as a routine analysis, and were applied in the determination of chlorpyrifos in water samples from five points along the Rio Dourados, near the city of Fatima do Sul.