四氧化三铁/单壁碳纳米管磁性复合纳米粒子分散固相微萃取-高效液相色谱法测定牛奶中的香精添加剂

通过化学键合的方法制备单壁碳纳米管包覆的四氧化三铁(Fe3O4/C N T s)磁性复合纳米粒子。首先用水热法合成磁性Fe3O4纳米粒子,并进行硅烷氨基化处理,羧基化的单壁碳纳米管通过1-(3-二甲基氨基丙基)-3-乙基碳二亚胺(EDC)和N-羟基琥珀酰亚胺(NHS)交联剂反应修饰到Fe3O4纳米颗粒表面。合成的Fe3O4/C N T s复合纳米粒子具有很高的磁响应度和很好的分散能力,是一种很好的分散固相萃取剂。本研究将合成的Fe3O4/C N T s纳米粒子用于分散固相微萃取富集牛奶中的香精添加剂,并与高效液相色谱分析联用,实现了香兰素和乙基香兰素的快速高效富集和高灵敏度检测,两者的检出限达10μg/L,回收率大于92%。本研究表明,合成的Fe3O4/C N T s磁性复合粒子是一种很好的奶制品中香兰素添加剂的样品前处理富集材料。

Dispersive solid phase microextraction of vanillins in milk using magnetic nanoparticles of ferroferric oxide/carbon nanotubes combining with high performance liquid chromatography analysis

Magnetic nanoparticles of ferroferric oxide/carbon nanotubes (Fe₃O₄/CNTs) were synthesized by chemically bonding single-walled carbon nanotubes (SWCNTs) to the Fe₃O₄ nanoparticles. The pretreated carboxyl SWCNTs were modified on the surface of amino-functioned Fe₃O₄ nanoparticles through the cross-linking reaction between 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS). The synthesized Fe₃O₄/CNTs nanoparticles presented high super paramagnetic property and good dispersion ability, and were considered as good candidate adsorbents for dispersive solid phase microextraction. In this work, the synthesized Fe₃O₄/CNTs nanoparticles were applied to the extraction of vanillin additives, which was combined with high performance liquid chromatography (HPLC) analysis. The rapid and efficient preconcentration of vanillin and ethyl vanillin from different milk samples were successfully obtained with the detection limits of 10 μg/L and satisfactory recoveries of more than 92%. The results indicated that Fe₃O₄/CNTs magnetic nanoparticles were good pretreatment alternatives for the concentration of vanillin additives in milk products.