Boulanouar Sara, Combès Audrey, Mezzache Sakina, Pichon Valérie
Dept of Analytical, Bioanalytical Sciences and Miniaturization (LSABM) - UMR CBI 8231 (CNRS-ESPCI), ESPCI, PSL Research University, 10 rue Vauquelin, 75 231 Paris Cedex 05, France.
L'Oréal Research and Innovation, 1 avenue Eugène Schueller BP22, 93601 Aulnay sous Bois, France.
J Chromatogr A. 2017 Sep 1;1513:59-68. doi: 10.1016/j.chroma.2017.07.067. Epub 2017 Jul 20.
The increasing use of pesticides in agriculture causes environmental issues and possible serious health risks to humans and animals. Their determination at trace concentrations in vegetable oils constitutes a significant analytical challenge. Therefore, their analysis often requires both an extraction and a purification step prior to separation with liquid chromatography (LC) and mass spectrometry (MS) detection. This work aimed at developing sorbents that are able to selectively extract from vegetable oil samples several organophosphorus (OPs) pesticides presenting a wide range of physico-chemical properties. Therefore, different conditions were screened to prepare molecularly imprinted polymers (MIPs) by a non-covalent approach. The selectivity of the resulting polymers was evaluated by studying the OPs retention in pure media on both MIPs and non-imprinted polymers (NIP) used as control. The most promising MIP sorbent was obtained using monocrotophos (MCP) as the template, methacrylic acid (MAA) as the monomer and ethylene glycol dimethacrylate (EGDMA) as the cross-linker with a molar ratio of 1/4/20 respectively. The repeatability of the extraction procedure and of the synthesis procedure was demonstrated in pure media. The capacity of this MIP was 1mg/g for malathion. This MIP was also able to selectively extract three OPs from almond oil by applying the optimized SPE procedure. Recoveries were between 73 and 99% with SD values between 4 and 6% in this oil sample. The calculated LOQs (between 0.3 and 2μg/kg) in almond seeds with a SD between 0.1 and 0.4μg/kg were lower than the Maximum Residue Levels (MRLs) established for the corresponding compounds in almond seed.
农业中农药使用的增加引发了环境问题，并对人类和动物造成了可能严重的健康风险。在植物油中痕量测定这些农药构成了重大的分析挑战。因此，在通过液相色谱（LC）和质谱（MS）检测进行分离之前，它们的分析通常需要萃取和净化步骤。这项工作旨在开发能够从植物油样品中选择性萃取多种具有广泛物理化学性质的有机磷（OPs）农药的吸附剂。因此，通过非共价方法筛选了不同条件来制备分子印迹聚合物（MIPs）。通过研究在纯介质中OPs在用作对照的MIPs和非印迹聚合物（NIP）上的保留情况，评估了所得聚合物的选择性。使用久效磷（MCP）作为模板、甲基丙烯酸（MAA）作为单体和乙二醇二甲基丙烯酸酯（EGDMA）作为交联剂，分别以1/4/20的摩尔比获得了最有前景的MIP吸附剂。在纯介质中证明了萃取过程和合成过程的可重复性。这种MIP对马拉硫磷的容量为1mg/g。通过应用优化的固相萃取（SPE）程序，这种MIP还能够从杏仁油中选择性萃取三种OPs。在该油样中，回收率在73%至99%之间，标准偏差（SD）值在4%至6%之间。在杏仁种子中计算出的定量限（LOQs）（介于0.3和2μg/kg之间），标准偏差在0.1和0.4μg/kg之间，低于杏仁种子中相应化合物规定的最大残留限量（MRLs）。
