Department of Chemistry, Payame Noor University, Mashhad, Iran.
J Sep Sci. 2013 Jan;36(2):311-9. doi: 10.1002/jssc.201200556. Epub 2012 Nov 29.
In this research, solvent-assisted dispersive micro-SPE was introduced as a simple modified technique for the determination of parabens in water and cosmetic samples. Aminopropyl-functionalized magnetite nanoparticles (MNPs) were successfully synthesized and applied. GC with photoionization detector was used for the separation and detection of parabens. In this method, hexylacetate (15 μL) as a solvent and aminopropyl-functionalized MNPs (5 μg) as a sorbent were added to an aqueous sample (10 mL) and then the sample was sonicated. Dispersed magnetite was collected in the bottom of the conical tube by using a strong magnet and then ACN was added as a desorption solvent. Forty microliters of this solvent was transferred into a microvial and then acetic anhydride and pyridine were added, thus derivatization was performed by acetic anhydride. After evaporation, 1 μL of derivatized sample was injected into a gas chromatograph for analysis. Several important parameters, such as kind of organic solvent, desorption solvent and volume, amount of aminopropyl-functionalized MNPs and effect of salt addition were investigated. Under optimum conditions, the limits of detection achieved were between 50 and 300 ng/L, with RSDs (n = 5) lower than 8%. Under the optimum conditions, the enrichment factors ranged from 217 to 1253 and the extraction recoveries ranged from 10 to 62%. The recoveries were obtained for the analytes in river water and mouthwash solution and hand cream in the range of 87-103%. The advantages of proposed method are simplicity of operation, rapidity, high extraction yields, and environmental friendly character.
在这项研究中，引入了溶剂辅助分散微固相萃取作为一种简单的改进技术，用于测定水中和化妆品样品中的对羟基苯甲酸酯。成功合成并应用了氨丙基功能化磁铁矿纳米粒子（MNPs）。采用气相色谱-光电离检测器对对羟基苯甲酸酯进行分离和检测。在该方法中，向水样（10 mL）中加入 15 μL 的己酸乙酯作为溶剂和 5 μg 的氨丙基功能化 MNPs 作为吸附剂，然后对样品进行超声处理。磁性纳米粒子通过使用强磁铁收集在锥形管的底部，然后加入 ACN 作为解吸溶剂。将 40 μL 该溶剂转移到微管中，然后加入醋酸酐和吡啶，通过醋酸酐进行衍生化。蒸发后，将衍生化后的样品 1 μL 注入气相色谱仪进行分析。研究了几种重要的参数，如有机溶剂的种类、解吸溶剂的种类和体积、氨丙基功能化 MNPs 的用量以及加盐的影响。在最佳条件下，检测限在 50 到 300ng/L 之间，相对标准偏差（n=5）低于 8%。在最佳条件下，富集因子范围为 217 到 1253，萃取回收率范围为 10 到 62%。在河水、漱口液和护手霜中，分析物的回收率在 87-103%之间。该方法的优点是操作简单、快速、萃取效率高、环境友好。
