高效液相色谱法测定乳粉中玉米黄质含量

Determination of Zeaxanthin in Milk Powder by High Performance Liquid Chromatography

建立乳粉中玉米黄质含量的高效液相色谱测定方法。室温条件下,乳粉样品经氢氧化钾溶液皂化,使玉米黄质游离,再以乙醚-正己烷-环己烷混合溶剂提取,冷冻脱脂,采用梯度洗脱程序进行洗脱,C30色谱柱分离,紫外检测器检测,外标法定量。结果表明:乳粉中玉米黄质的检出限为30μg/100 g,定量限为100μg/100 g;当乳粉中玉米黄质加标量为90~811μg/100 g时,加标回收率为85.8%~102.2%,相对标准偏差为1.43%~2.76%。该方法具有较好的准确度、精密度和重复性,灵敏度较高。

A method for the determination of zeaxanthin in milk powder was developed using high performance liquid chromatography(HPLC).The sample was saponified with potassium hydroxide solution to release zeaxanthin,extracted with a mixed solvent of ethyl ether,n-hexane and cyclohexane and frozen for degreasing.The chromatographic separation was performed on a C30 column with gradient elution.The analyte was detected with an ultraviolet detector and quantified by an external standard method.The limit of quantification was 100μg/100 g and the limit of detection was 30μg/100 g for zeaxanthin in milk powder.The method recoveries at spiked concentration levels of 90–811μg/100 g were 85.8%–102.2%,with relative standard deviations ranging from 1.43%to 2.76%.This method was accurate,repeatable,precise and sensitive.