高效液相色谱法测定食品中的酸性橙Ⅱ

HPLC Determination of Acid Orange 7 in Foods

建立食品中非食用色素酸性橙Ⅱ的高效液相色谱快速检测方法。样品用饱和乙腈提取,经饱和正己烷萃取除去油溶性色素及杂质,采用高效液相色谱柱分离,二极管阵列检测器(DAD)检测,结合标准物质保留时间和DAD光谱图进行定性分析,外标法定量。色谱柱为AgilentZORBAXSB-C18(150mm×4.6mm,5μm),流动相为乙腈-体积分数0.3%醋酸溶液进行梯度洗脱,检测波长为484nm,线性范围为0.01～1.0μg/mL,相关系数R2=0.9997。采用本方法对乳制品、辣椒粉、辣椒酱、卤肉制品、卤蛋、卤豆腐干6种常见基质进行验证,结果表明,HPLC-DAD测定食品中的酸性橙Ⅱ,对于1.0g样品定容至5mL、进样量为20μL时,检出限为0.05mg/kg;添加标准回收实验表明,本方法在添加水平分别为0.05、0.1、0.2mg/kg时的样品平均回收率在74.9%～100.0%之间,相对标准偏差(RSD)在1.41%～8.64%之间(n=6)。本方法准确、可靠。

A high-performance liquid chromatographic（HPLC） method was developed for the determination of acid orange 7 in foods.Samples were extracted with n-hexane saturated acetonitrile,and the extract was then extracted twice with acetonitrile saturated n-hexane for the removal of oily pigments and other impurities.The resulting lower phase was subjected to HPLC analysis using Agilent ZORBAX SB-C18 column set at 40 ℃ followed by detection with a diode array detector（DAD） detector at 484 nm.Binary linear gradients were achieved using mobile phase A：acetonitrile and mobile phase B：0.3% acetic acid aqueous solution at a flow rate of 1.0 mL/min.The calibration curve for determination of acid orange 7 by the method exhibited good linearity over the concentration from 0.01 to 1.0 mg/L with a correlation coefficient of 0.9997 and the limit of detection（LOD） of the method was 0.05 mg/kg.Mean recoveries of 6 replicates for acid orange 7 in 6 different matrix samples spiked at the levels of 0.05,0.1 mg/kg and 0.2 mg/kg ranged between 74.9% and 100%,with a relative standard deviation（RSD） range of 1.41% to 8.64%.The method proved good in intra-laboratory accuracy and precision.