Oliveira Amilton Moreira, Loureiro Hugo Campos, de Jesus Francielly Fernanda Souza, de Jesus Dosil Pereira
Institute of Chemistry, University of Campinas, UNICAMP, Campinas, SP, Brazil.
Instituto Nacional de Ciência e Tecnologia de Bioanalítica, Campinas, SP, Brazil.
J Sep Sci. 2017 Apr;40(7):1532-1539. doi: 10.1002/jssc.201601305. Epub 2017 Mar 7.
Electromembrane extraction using a polypropylene hollow fiber impregnated with 1-ethyl-2-nitrobenzene was evaluated for the extraction and preconcentration of the fungicides thiabendazole and carbendazim from water samples before capillary electrophoresis analysis. The composition of the supported liquid membrane, the HCl concentration in the acceptor solution, and the stirring rate (of the donor solution) were optimized using the one-variable-at-a-time method. In contrast, a face-centered central composition design was used for optimization of voltage, extraction time, and concentration of HCl in the donor solution. After optimization, electromembrane extraction provided enrichment factors of 50 and 26 for thiabendazole and carbendazim that allowed us to achieve limits of detection of 1.1 and 2.3 μg/L, respectively. Repeatability (intraday precision) expressed as the relative standard deviation varied from 2.5 to 2.8%, while the interday precision ranged from 3.1 to 3.3%. The proposed method was applied for analysis of samples of tap and river water, and acceptable precision and accuracy were attained.
在进行毛细管电泳分析之前，评估了使用浸渍有1-乙基-2-硝基苯的聚丙烯中空纤维进行电膜萃取，以从水样中萃取和预富集杀菌剂噻菌灵和多菌灵。采用一次变量法对支撑液膜的组成、接受相溶液中的HCl浓度以及（供体溶液的）搅拌速率进行了优化。相比之下，采用面心中心组合设计对电压、萃取时间和供体溶液中HCl的浓度进行优化。优化后，电膜萃取对噻菌灵和多菌灵的富集因子分别为50和26，这使得我们分别实现了1.1和2.3 μg/L的检测限。以相对标准偏差表示的重复性（日内精密度）在2.5%至2.8%之间变化，而日间精密度在3.1%至3.3%之间。所提出的方法应用于自来水和河水样品的分析，并获得了可接受的精密度和准确度。
