UHPLC-MS/MS Determination of Cholesterol in Edible Vegetable Oil

A method for the determination of cholesterol in edible vegetable oil by ultra-high-performance liquid chromatography hyphenated with tandem mass spectrometry (HPLC-MS/MS) was proposed. Cholesterol in samples was extracted with a mixture of petroleum ether and ethyl ether (1+1). The eluate was used for UHPLC-MS/MS determination, in which the ACQUITY UPLC BEH C18 column (50 mm×2.1 mm, 5 μm) was used as separation column, a mixture of formic acid and methanol (0.1+99.9) was used as mobile phase, and 2,2,3,4,4,6-d6-cholesterol was used as internal standard. Atmospheric pressure chemical electrospray ionization under the mode of multiple reaction monitoring was used in the detection. Ion pairs used for the quantitative analysis were m/z 369.2/146.9, 369.2/160.9 for cholesterol and m/z 375.2/166.5 for internal standard. Linearity range was found between 0.1-5 mg·L-1, and lower limit of determination (10S/N) found was 0.02 ng. Recovery was tested at 3 concentration levels, giving results of recovery ranged from 102% to 110%.