Hollow fiber-liquid-phase microextraction of fungicides from orange juices
Hollow fiber-liquid-phase microextraction of fungicides from orange juices
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DOI：
10.1016/j.chroma.2010.01.077
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发表时间：
2010-03-26
影响因子：
4.1
通讯作者：
Rasmussen, Knut Einar
中科院分区：
文献类型：
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作者：
Barahona, Francisco;Gjelstad, Astrid;Rasmussen, Knut Einar
研究了聚丙烯中空纤维液相微萃取法（LPME）从橙汁中提取采收后杀菌剂噻苯达唑（TBZ）、多菌灵（CBZ）和伊马唑利（IMZ）的工艺条件。直接进行LPME，在提取前没有任何样品预处理，使用简单的自制设备。在3 mL橙汁中加入500 μ L 840 mM NaOH，以补偿样品的酸性，将pH调节到碱性区域。分析物在中性状态下通过2-辛酮支撑液膜（SLM）提取到中空纤维管腔内20 wL的10mM盐酸停滞水溶液中。随后，直接对受体溶液进行分析。采用毛细管电泳法对提取工艺进行优化。在优化的提取条件下，无论样品中存在不同的pH值或固体物质（纸浆），LPME都能有效地提取不同的橙汁中的分析物，回收率在17.0% ~ 33.7%之间。采用液相色谱-质谱联用（LC/MS）评价了该方法的分析性能。该技术具有比CE更好的灵敏度，并且可以检测到μ μ L（-1）以下的水平。回收率的相对标准偏差（rsd）在3.4 ~ 10.6%之间，在未经任何样品处理的情况下，使用自制设备，在非平衡条件下（提取30 min）进行人工微提取技术，可接受的值。TBZ和IMZ在0.1 ~ 10.0 μ g L（-1）范围内呈线性关系，r分别为0.999和0.998。检测限低于0.1 μ g L(-1)，符合饮用水中农药允许的最大残留限量，这是适用于这类样品的最严格的规定。它已经证明了三相LPME从柑桔汁中提取农药的适用性，抑制了任何预处理步骤，如过滤或从样品中去除固体物质，这可能涉及分析物的损失。(C) 2010 Elsevier B.V.版权所有
Liquid-phase microextraction (LPME) based on polypropylene hollow fibers was evaluated for the extraction of the post-harvest fungicides thiabendazole (TBZ), carbendazim (CBZ) and imazalil (IMZ) from orange juices. Direct LPME was performed without any sample pretreatment prior to the extraction, using a simple home-built equipment. A volume of 500 mu L of 840 mM NaOH was added to 3 mL of orange juice in order to compensate the acidity of the samples and to adjust pH into the alkaline region. Analytes were extracted in their neutral state through a supported liquid membrane (SLM) of 2-octanone into 20 wL of a stagnant aqueous solution of 10mM HCl inside the lumen of the hollow fiber. Subsequently, the acceptor solution was directly subjected to analysis. Capillary electrophoresis (CE) was used during the optimization of the extraction procedure. Working under the optimized extraction conditions, LPME effectively extracted the analytes from different orange juices, regardless of different pH or solid material (pulp) present in the sample, with recoveries that ranged between 17.0 and 33.7%. The analytical performance of the method was evaluated by liquid chromatography coupled with mass spectrometry (LC/MS). This technique provided better sensitivity than CE and permitted the detection below the mu g L(-1) level. The relative standard deviations of the recoveries (RSDs) ranged between 3.4 and 10.6%, which are acceptable values for a manual microextraction technique without any previous sample treatment, using a home-built equipment and working under non-equilibrium conditions (30 min extraction). Linearity was obtained in the range 0.1-10.0 mu g L(-1), with r=0.999 and 0.998 for TBZ and IMZ, respectively. Limits of detection were below 0.1 mu g L(-1) and are consistent with the maximum residue levels permitted for pesticides in drinking water, which is the most restrictive regulation applicable for these kinds of samples. It has been demonstrated the suitability of three-phase LPME for the extraction of pesticides from citrus juices, suppressing any pretreatment step such as filtration or removal of the solid material from the sample, that may potentially involve a loss of analyte. (C) 2010 Elsevier B.V. All rights reserved.