Barro Ruth, Garcia-Jares Carmen, Llompart Maria, Bollain Maria Herminia, Cela Rafael
Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Quimica, Instituto de Investigacion y Analisis Alimentario, Universidad de Santiago de Compostela, Spain.
J Chromatogr A. 2006 Apr 7;1111(1):1-10. doi: 10.1016/j.chroma.2006.01.093. Epub 2006 Feb 3.
A fast and simple method to analyze pyrethroids as well as other components of frequently used domestic insecticide preparations in indoor air is presented. The proposed method, based on sampling with an adsorbent followed by ultrasound-assisted solvent extraction, was developed with the aim to simplify the traditional extraction methodologies applied up to date to determine pesticides in air. The analytes were retained on a very small amount of adsorbent, which allowed using solely 1 mL of solvent for desorption. The quantification was performed by gas chromatography with microelectron-capture detection (GC-muECD) and gas chromatography coupled to mass spectrometry (GC-MS). The influence of main factors involved in the ultrasound-assisted solvent extraction step (type of adsorbent and type of solvent, solvent volume and extraction time) was studied using an experimental design approach to account for possible factor interactions. The sampling step was studied for two adsorbents (Tenax TA and Florisil), finding that 1 m(3) air could be sampled without losses of analytes. In this way, the analysis of pyrethroids in air by the proposed method could be carried out within a total time shorter than an hour, including sampling. Linearity was demonstrated in a wide concentration range. Efficiency of the total sampling-extraction process was studied at several concentration levels (2, 10, 100 and 1000 ng/m(3)), obtaining quantitative recoveries for all compounds, with good precision (RSD < 10%). Method detection limits were below 1 ng/m(3) in air when GC-muECD was employed, and about one order of magnitude higher for GC-MS. In addition, the proposed method was applied to real samples collected in contaminated closed rooms, in which some of the target compounds were determined.
本文介绍了一种快速简便的方法，用于分析室内空气中拟除虫菊酯以及常用家用杀虫剂制剂的其他成分。所提出的方法基于用吸附剂采样，随后进行超声辅助溶剂萃取，旨在简化迄今为止用于测定空气中农药的传统萃取方法。分析物保留在极少量的吸附剂上，这使得仅使用1 mL溶剂进行解吸。通过带有微电子捕获检测的气相色谱法（GC-μECD）和与质谱联用的气相色谱法（GC-MS）进行定量分析。使用实验设计方法研究了超声辅助溶剂萃取步骤中涉及的主要因素（吸附剂类型和溶剂类型、溶剂量和萃取时间）的影响，以考虑可能的因素相互作用。对两种吸附剂（Tenax TA和弗罗里硅土）的采样步骤进行了研究，发现可以采集1 m³空气而不会损失分析物。通过这种方式，使用所提出的方法分析空气中的拟除虫菊酯，包括采样在内，总时间可在不到一小时内完成。在很宽的浓度范围内证明了线性关系。在几个浓度水平（2、10、100和1000 ng/m³）下研究了整个采样-萃取过程的效率，所有化合物均获得定量回收率，精密度良好（RSD < 10%）。当采用GC-μECD时，空气中的方法检测限低于1 ng/m³，而GC-MS的检测限高约一个数量级。此外，所提出的方法应用于在受污染的封闭房间中采集的实际样品，其中测定了一些目标化合物。
