Cholesterol Removal from Milk Nvith Crossed linked B- cyclodextrin and Determination of Cholesterol by High Performance Liquid Chromatography

A sensitive and high-performance liquid chromatographic method has been developed to determine the cholesterol content in milk and dairy products. A comparison was made between acetonitrile: 2-propanol (8:1, v/v), acetonitrile: methanol (3:1, v/v), and acetonitrile: methanol: 2-propanol (7:3:1, v/v) for optimizing cholesterol separation. In comparison with other mobile phase systems for separating cholesterol, acetonitrile/methano1/2-propanol was the best. To remove interfering compounds, the liquid-liquid extraction (LLE) of cholesterol was simplified with hexane, a nonpolar solvent that has a high recovery (100±1.0%) of cholesterol. Sep-pak Cl8 was used to develop a solid phase extraction (SPE) method that was compared with liquid phase extraction (LLE).There was high reproducibility and rapidity in the SPE method. In combination with saponification of esterified cholesterol, both extraction methods were useful to determine total cholesterol. It was possible to detect cholesterol at a level of 0.01 ig.  This new HPLC method has advantages over traditional methods because it is simple, rapid, and accurate.