Utility of 19-Hydroxycholesterol as an Internal Standard Compound for the Quantitative Determination of Sterols Using Capillary Gas Chromatograph

Gas chromatography is able to detect many kinds of sterols simultaneously. In order to identify and estimate accurately many kinds of sterols in biological samples by gas chromatography, it is indispensable to add an internal standard compound into the analytical samples prior to the analysis. However, there is no report on a suitable internal standard compound for the determination of sterols. In this study, 19-hydroxycholesterol was proved to be a suitable internal standard compound for simultaneous and quantitative determination of several sterols in various analytical samples by capillary gas chromatography, including the quantitative determination of β-cholestanol in the human plasma. Moreover, the excellent condition of gas chromatographic analysis for quantitative determination of several sterols in various analytical samples was found.