LC—ESI／MS分析食品中微量苏丹红Ⅰ～Ⅳ

Determination of Trace SudanⅠ-Ⅳin Food by HPLC-ESI/MS

建立了准确可靠的用LC-ESI/MS分析食品中4种苏丹红色素的方法.样品中的苏丹红用乙腈提取,不需纯化.色谱柱为Agilent C18(15 cm×2.1 mm,3μm),流动相为乙腈-0.5%乙酸溶液(体积比72:28).采用正离子电离方式,每种化合物选择3个碎片离子为定性离子以获得高选择性,选取每个化合物丰度最高的碎片为定量离子以获得高灵敏度.4种苏丹红色素的检出限(LOD)和定量下限(LOQ)均为ng/g水平.标准加入量为0.2μg/g水平时的回收率为86%～98%,且重复性良好.本方法仪器分析时间仅需8 min,适合于大量样品的日常快速分析.

A rapid and reliable method for the determination of trace SudanⅠ,Ⅱ,ⅢandⅣin food stuffs by reversed-phase liquid chromatography-ESI/MSD was presented.The Sudan dyes were extracted with acetonitrile and the clean-up procedure was not required.An Agilent C 18 (15cm×2.1mm)column with acetonitrile-0.5%acetic acid mixture as the mobile phase was used under isocratic conditions(72∶28by volume).The mass spectra was acquired in positive ion mode.For each compound,three fragment ions were selected as qualitative ions to obtain high selectivity,and the most abundant fragment of each com-pound was selected for quantification to obtain high sensitivity.The detection limits(LOD)and quantification limits(LOQ)of SudanⅠ-Ⅳwere atμg/g levels.The extraction recoveries of Sudan dyes in red pepper products ranged from86%to98%with good reproducibility at a spiking level of0.2μg/g.The time for the instrumental analysis was only8min.The method is applicable for routine analysis.