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Carbon nanotubes as solid-phase extraction sorbents for the extraction of carbamate insecticides from environmental waters
Latrous El Atrache, L.; Hachani, M. & Kefi, B.B.
Abstract
Multiwalled carbon nanotubes have been used
for the first time as solid-phase extraction sorbents for the
extraction of five N-methylcarbamate insecticides (i.e.,
carbaryl, carbofuran, aminocarb, methiocarb, and zectran)
from different surface water samples. An effective and
sensitive method was developed by combining solid-phase
extraction and liquid chromatography–electrospray ionization–
mass spectrometry detection. Important parameters
influencing the extraction efficiency such as kind and
volume of elute, volume of water samples, and adsorbent
mass were optimized. Under the optimized extraction
conditions, good linearity was obtained for all carbamates
(r2 > 0.995) over the range of 0.005–1 mg L-1. The limits
of detection and quantification were 0.01–0.05 and
0.08–0.2 µg L-1, respectively. The optimized solid-phase
extraction procedure was compared in terms of adsorption
capacity to C18 silica and activated carbon. The adsorption
capacity of multiwalled carbon nanotubes was larger than
activated carbon. The proposed method was successfully
applied to the analysis of tap and surface waters, and mean
recoveries for five carbamates were from 92.2 to 103.9 %
with relative standard deviation between 0.4 and 7.0 %.
Keywords
Carbamate pesticides; Multiwalled carbon nanotubes; Solid-phase extraction; Water; Liquid chromatography–mass spectrometry
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