Cold Saponification Method for Determination of 5 Lutein Stereoisomers in Dairy Products by High Performance Liquid Chromatography / 分析化学

ABSTRACT

A cold saponification method for determination of 5 lutein stereoisomers in dairy products by high performance liquid chromatography ( HPLC ) was developed. Samples were cold-saponified at room temperature and extracted by n-hexane/petroleum/dichloromethane ( 2 2 1 , V/V/V ) . Then 5 lutein stereoisomers were separated on a YMC C30 column with gradient elution using methanol/methyl tert-butyl ether as the mobile phase, and data were acquired by a photodiode array detector at wavelength of 445 nm. The calibration curve was linear in the range of 0 . 127-5 . 082 mg/L with correlation coefficient of 0 . 9999 , and the recoveries were from 96 . 7% to 102 . 2% with the RSDs in the range of 4 . 1%-5 . 4% ( n=6 ) . The limit of detection was 0 . 010 μg/g ( S/N=3 ) , and the limit of quantification was 0 . 030 μg/g ( S/N=10 ) . By presenting results of good accuracy, precision and sensitivity, this method validates its suitability for routine analysis of 5 lutein stereoisomers in dairy products.