Use of Multiwalled Carbon Nanotubes as a SPE Adsorbent for Analysis of Carfentrazone-Ethyl in Water

Abstract

Solid-phase extraction and gas chromatography with electron-capture detection has been used for sensitive, simple, and reliable analysis of carfentrazone-ethyl residues in water. Carfentrazone-ethyl was enriched by use of multiwalled carbon nanotubes (MWCNT), a new adsorptive material. Several conditions affecting recovery of the analyte, for example polarity and volume of eluents, pH of water samples, and sample volume, were studied. Recovery from fortified samples, linear range, and limit of detection were evaluated. The results showed that MWCNT are an efficient SPE adsorbent for preconcentration of carfentrazone-ethyl in water. Under the optimized SPE conditions, recovery of carfentrazone-ethyl from fortified water was 81.49–91.08%, with RSD from 1.66 to 8.21%. The limits of detection and quantification were 0.01 and 0.03 µg L−1, which were lower than the MRL stipulated by the EU for individual pesticides in water (0.1 µg L−1). Finally, the method was applied to tap water and river water; the results showed that the method was suitable for detection of carfentrazone-ethyl in environmental water samples.