Jiao Zhe, Zhang Yan, Fan Hongbo
College of Chemistry and Environmental Engineering, Dongguan University of Technology, Dongguan 523808, China.
College of Chemistry and Environmental Engineering, Dongguan University of Technology, Dongguan 523808, China.
J Chromatogr A. 2016 Jul 29;1457:7-13. doi: 10.1016/j.chroma.2016.06.041. Epub 2016 Jun 16.
In this study, a nanocomposite of polypyrrole-coated magnetite nanoparticles (Fe3O4@PPy) was prepared by ultrasonic-microwave technique, and employed as magnetic solid-phase extraction (MSPE) sorbent for extraction of vitamin D from milk samples. The term of the synthesis by ultrasonic-microwave technique was dramatically shortened within 4h compared to 20h by conventional stirring-heating method. The resultant composites incorporating the π-π bonding (between PPy coating and the analytes) and magnetic separation can be applied for vitamin D analysis in complicated samples. Without saponification or protein precipitation, vitamin D2 and vitamin D3 could be captured directly from milk samples by Fe3O4@PPy, and separated by magnetic field with only 0.5mL desorption solvent. The total preparation time was completed within 15min. A method for the determination of vitamin D in milk samples by the Fe3O4@PPy extraction coupled with high performance liquid chromatography (HPLC) was developed. The LODs of vitamin D2 and vitamin D3, based on signal-to-noise ratio (S/N) of 3, were 0.02ng/mL and 0.05ng/mL respectively. The recoveries of vitamin D2 and vitamin D3 from milk samples were in the range of 71.9-90.3%, with relative standard deviations ranging between 3.6%-9.9%. The results indicated that the Fe3O4@PPy can be favorably used for the extraction of the vitamin D in milk samples.
在本研究中，采用超声-微波技术制备了聚吡咯包覆磁铁矿纳米颗粒（Fe3O4@PPy）的纳米复合材料，并将其用作磁性固相萃取（MSPE）吸附剂，用于从牛奶样品中萃取维生素D。与传统搅拌加热法20小时相比，超声-微波技术合成时间大幅缩短至4小时以内。所得复合材料兼具π-π键合（PPy涂层与分析物之间）和磁分离功能，可用于复杂样品中维生素D的分析。无需皂化或蛋白质沉淀，Fe3O4@PPy可直接从牛奶样品中捕获维生素D2和维生素D3，仅用0.5mL解吸溶剂通过磁场进行分离。整个制备时间在15分钟内完成。建立了一种基于Fe3O4@PPy萃取结合高效液相色谱（HPLC）测定牛奶样品中维生素D的方法。基于信噪比（S/N）为3，维生素D2和维生素D3的检测限分别为0.02ng/mL和0.05ng/mL。牛奶样品中维生素D2和维生素D3的回收率在71.9-90.3%范围内，相对标准偏差在3.6%-9.9%之间。结果表明，Fe3O4@PPy可很好地用于牛奶样品中维生素D的萃取。
