高效液相色谱法测定奶粉中玉米黄质含量

Determination of zeaxanthin in milk powder by high performance liquid chromatography

中文关键词:  奶粉  玉米黄质  高效液相色谱法  紫外检测器

英文关键词:milk powder  zeaxanthin  high performance liquid chromatography  ultraviolet detector

中文摘要:

      目的 建立高效液相色谱法检测奶粉中玉米黄质含量的分析方法。方法 奶粉样品用蛋白酶在45 ℃条件下振荡酶解30 min, 正己烷:丙酮(9:1, V:V)重复提取2次, 旋转蒸发浓缩至近干, 正己烷:乙酸乙酯(65:35, V:V)复溶后, 用Si 60 (100 mm×2.1 mm, 5 μm)色谱柱经高效液相色谱紫外检测器测定, 外标法定量。结果 玉米黄质在14.018 min附近出峰, 玉米黄质浓度在0.0~4.0 μg/mL范围内呈良好线性关系(r2=0.99982)。在添加玉米黄质含量为63.3、126.7、316.7 μg/100 g时, 加标回收率在95.8%~96.7%之间, 相对标准偏差在1.1%~3.9%之间, 检出限为20 μg/100 g, 定量限为50 μg/100 g。结论 该方法可以检测奶粉中玉米黄质的含量, 与其他前处理方法相比较简单, 且具有较高的准确度、稳定性和灵敏度, 对之后的检测应用具有重大意义。

英文摘要:

      Objective To establish a method for the determination of zeaxanthin content in milk powder by high performance liquid chromatography. Methods The milk powder sample was enzymatically hydrolyzed with protease at 45 ℃ for 30 min, extracted 2 with n-hexane:acetone (9:1, V:V) repeatly, concentrated by rotary evaporation, reconstituted with n-hexane:ethyl acetate (65:35, V:V), determined by high performance liquid chromatography ultraviolet detector using Si 60 (100 mm×2.1 mm, 5 μm) column, and quantitatively determined by external standard method. Results The zeaxanthin peaked around 14.018 min, and the zeaxanthin concentration had a good linear relationship in the range of 0.0?4.0 μg/mL (r2=0.99982). When the content of zeaxanthin were 63.3, 126.7, 316.7 μg/100 g, the recoveries of standard addition were between 95.8% and 96.7%, and the relative standard deviations were between 1.1% and 3.9%. The limit of detection was 20 μg/100 g and the limit of quantification was 50 μg/100 g. Conclusion This method can detect the content of zeaxanthin in milk powder, is simpler than other pre-processing methods, and has higher accuracy, stability and sensitivity, and which is of great significance for subsequent detection applications.