Determination of cholesterol using o-phthalaldehyde

Abstract

A simple, rapid method for the determination of cholesterol in plasma and tissue using o-phthalaldehyde is presented. Comparison of this method with the FeCl3 method gave identical results. However, the o-phthalaldehyde determination is three times more sensitive than the FeCl3 determination (molar extinction coefficients of 11,610 and 33,440 for FeCl3 and o-phthalaldehyde, respectively), it takes less time to complete, and the color developed is more stable. The o-phthalaldehyde method can be used to assay free and esterified cholesterol directly after thin-layer chromatographic separation.

Keywords

• cholesteryl ester
• FeCl3
• thin-layer chromatography