磺化改性聚四氟乙烯纤维固相萃取-高效液相色谱联用测定奶制品中的三聚氰胺

Sulfonation Modification of the Polytetrafluoroethene Fiber for Solid Extraction Coupled with High-performance Liquid Chromatography for Determination of Trace Melamine in Milk Preparations

采用新型固相萃取材料磺化的甲基丙烯酸缩水甘油酯接枝聚四氟乙烯(PTFE-g-GMA-SO3H)纤维填充微柱预富集和流动注射(FI)与高效液相色谱(HPLC)联用测定样品中痕量的三聚氰胺。建立了以该纤维作为吸附剂在线测定奶制品中三聚氰胺的新方法。对三聚氰胺的富集与洗脱条件进行了优化,并得出三聚氰胺的分析特性:该方法对三聚氰胺的检出限为1.13×10-2 mg/L,富集倍数为300,RSD为7.6%(n=9,三聚氰胺质量浓度为0.2 mg/L)。该方法应用于2种奶制品中的痕量三聚氰胺的测定,样品加标回收率分别为98%和102.5%。

A preconcentration column packed with home-made sulfonated glycidyl methacrylate（GMA）-grafted-polytetrafluoroethylene（PTFE） polymer（PTFE-g-GMA-SO3H） fiber,coupled with high-performance liquid chromatography（HPLC） and flow injection,fiber was developed for trace melamine determination in the samples.The on-line determination method using the fiber as adsorbent for trace melamine in two milk sample was demonstrated.The conditions for preconcentration and elution of melamine were optimized.In addition,analytical performance of trace melamine determination was acquired in this article.The enrichment factor for melamine was 300 and the detection limits was 1.13×10-2 mg/L.The relative standard derivation was 7.6%（n=9） when the melamine concentration was 0.2 mg/L,and the recovery of samples was 98% and 102.5%,respectively.