柱前衍生-高效液相色谱-质谱联用法鉴定糖浆 掺假蜂蜜

目的建立蜂蜜中掺假的快速鉴定方法。方法将蜂蜜样品溶解后进行真空干燥,然后对样品中的低聚糖进行荧光标记,以氨基柱为分析柱,采用乙腈和甲酸铵为流动相,对标记低聚糖进行高效液相色谱分离,采用ESI-MS的SIR模式对标记低聚糖进行定性测定。结果基于荧光标记试剂2-氨基苯甲酰胺(2-AB)和毒性较低的还原剂2-甲基吡啶-N-甲硼烷(2-PB)的还原氨化反应能有效地对蜂蜜中的带还原端的低聚糖进行荧光标记。天然蜂蜜含有单糖(DP1)、双糖(DP2)和少量三糖(DP3),掺假蜂蜜除此以外还含有少量四糖(DP4)、五糖(DP5)和六糖(DP6)。结论采用此法对蜂蜜样品进行蜂蜜掺假判定与国标方法测试结果基本吻合,而且不需对样品进行净化处理即可上机分析,为建立蜂蜜掺假的快速筛查方法提供参考。

Identification of adulterated honey by precolumn derivatization-high performance liquid chromatography-tandem mass spectrometry

Objective To establish a method for the determination of adulterated honey. Methods Honey samples were dissolved and treated by vacuum drying, and then they were fluorescent labeled before separated by high performance liquid chromatography (HPLC) using NH2 column with acetonitrile and ammonium formate as mobile phase, and qualitatively analyzed by ESI-MS under SIR mode. Results It was shown that the fluorescent labeling of oligosaccharides with reducing end in honey were effectively achieved when using 2-aminobenzamide and 2-picoline-borane following by reductive amination reaction. It was also shown that natural honey contained monosaccharide (DP1), disaccharide (DP2) and trisaccharide (DP3); in addition, adulterated honey contained tetrasaccharide (DP4), pentasaccharide (DP5) and hexasaccharide (DP6). Conclusion The results of the established method are basically consistent with those of the national standard method, and the established method do not need to purify the samples before HPLC analysis, which provide references for the rapid screening method of adulterated honey.