凝胶净化/超高效液相色谱电喷雾质谱法检测调味油中11种禁用偶氮染料及罗丹明B

建立了凝胶渗透色谱(GPC)净化/超高效液相色谱-电喷雾串联四极杆质谱(UPLC-MS/MS)同时检测调味油中11种脂溶性偶氮类工业染料(苏丹红Ⅰ、苏丹红Ⅱ、苏丹红Ⅲ、苏丹红Ⅳ、苏丹红7B、苏丹红G、苏丹黄、苏丹橙G、苏丹蓝Ⅱ、甲苯胺红、对位红)和罗丹明B的分析方法。样品经乙酸乙酯-环己烷(1∶1)提取,采用凝胶渗透色谱(GPC)去除大分子油脂、天然色素等干扰物质;以乙腈-0.1%甲酸为流动相,目标化合物在梯度洗脱条件下经C18柱分离后采用多离子反应监测(MRM)正离子模式进行检测。结果表明:调味油中12种工业染料的线性范围为1～50μg/L,定量下限(LOQ)为0.2～2.5μg/kg,在5、20、40μg/L 3个加标水平下的回收率为54%～125%,相对标准偏差为2.5%～17.2%。随机抽取市售35份样品进行检测,其中两份样品检出罗丹明B。该方法操作简便、灵敏度高,实现了11种禁用偶氮染料和罗丹明B的同时提取和净化,适合于调味油中非法添加脂溶性偶氮工业染料和罗丹明B的筛查与确证。

Determination of 11 Azo-dyes and Rhodamine B in Seasoning Oil by Gel Permeation Chromatography/Ultra Performance Liquid Chromatography with Electrospray Ionization Tandem Mass Spectrometry

An analytical method was developed for the simultaneous determination of 11 banned azo-dyes(Sudan red Ⅰ,Sudan red Ⅱ,Sudan red Ⅲ,Sudan red Ⅳ,Sudan red 7B,Sudan red G,Sudan yellow,Sudan orange G,Sudan blue Ⅱ,toluidine red,para red) and rhodamine B in seasoning oil based on gel permeation chromatography followed by ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The seasoning oil samples were extracted with cyclohexane-ethyl acetate(1∶1),and then purified by gel permeation chromatography to remove the high molecular weight of interferences(e.g.fat,oil and natural pigments).Twelve target compounds were separated on an ACQUITY UPLC BEH C18 column with 0.1% formic acid and acetonitrile as mobile phase by gradient elution,and detected by MS/MS under positive mode with multiple reaction monitoring(MRM).Good linearities for 12 dyes were achieved over the range of 1-50 μg/L.The quantitation limits of 12 dyes in seasoning oil samples were in the range of 0.2-2.5 μg/kg.The mean recoveries at three spiked level(5,20,40 μg/L) ranged from 54% to 125%,with relative standard deviations(RSDs) of 2.5%-17.2%.The method was used to analyze 35 seasoning oil samples taken randomly from the local market,and rhodamine B was found in 2 of the samples.The established method could be applied in the simultaneous extraction and purification of 11 azo-dyes and rhodamine B in seasoning oil matrix,and is suitable for the routine detection of illegally additive dyes in seasoning oil due to its simplicity and high sensitivity.