COMPARATIVE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC ANALYSES OF CHOLESTEROL AND ITS OXIDATION-PRODUCTS USING DIODE-ARRAY ULTRAVIOLET AND LASER LIGHT-SCATTERING DETECTION

Comparative high-performance liquid chromatographic (HPLC) analyses of cholesterol and its oxidization products (COPS) showed that cholester ol, cholestane, 7-ketocholesterol and 7 alpha, 7 beta-, 20- and 25-hyd roxycholesterol were detected by both ultraviolet (UV) and laser light -scattering detection (LLSD). In addition, the use of LLSD allowed the detection of cholestanetriol and alpha- and beta-epoxides. The limits of detection of COPS varied from 0.5 to 25 mu g/ml, depending on both the compound and the detector. The HPLC analyses demonstrated a linea r correlation between the UV response and concentrations of products i n the range 0-500 mu g/ml whereas a linear correlationship with LLSD w as obtained by plotting logarithmic coordinates in the same range.