Determination of vitamin D in oily drops using a column-switching system with an on-line clean-up by supercritical fluid chromatography

A column-switching system, composed of supercritical fluid chromatography (SFC) and reverse phase liquid chromatography/mass spectrometry (RPLC/MS) was constructed for the analysis of vitamin D in oily or fatty matrices. This system was successfully applied to the determination of vitamin D in oily drops, including Baby Ddrops and Vitamin AD drops without any fussy preparation.226