Extração em fase sólida (SPE) e microextração em fase sólida (SPME) para análise de agrotóxicos em água potável

Abstract

A currently faced problem is the contamination of water by pesticides, these compounds are difficult to identify and quantify because they occur in small concentrations. There are analytical methods such as gas chromatography that can identify and quantify these compounds. The greatest difficulty is in the preparation of the sample because it is necessary techniques that are capable of concentrating these analytes and favor an analysis with reliable results. The analysis methodologies are constantly changing in order to improve, in view of reduction in analysis time, use of reagents and cost, without losing the quality and effectiveness of the methods. For this reason, the study of sample preparation methodologies that have an efficient analytical concentration ratio, which is fast and low cost are necessary. The solid phase extraction (SPE) and the solid phase microextraction (SPME) were studied using two gas chromatographic analysis techniques. Through the elaboration of analytical curves, we evaluated parameters such as sensitivity, repeatability, time of analysis among others. After the evaluation of the analytical curves it can be observed that the technique that presented the best sensitivity was SPME being both techniques presented satisfactory results for the repeatability. In the parameter time of analysis the SPME presented better result. It was verified that of both techniques, the SPME proved to be the fastest and most practical, with better sensitivity, being the most suitable for the analysis of pesticides in water of human consumption, for analytes in low concentrations.