Fluorometric method for the enzymatic determination of cholesterol

A fluorometric method for the enzymatic determination of cholesterol content has been developed using a novel fluorogenic H2O2 probe, Amplex Red. This assay is performed in a 96-well microplate, and it is a one-step method amenable to automated procedures. Using commercially available cholesterol, our assay allows detection of 5 pmol (2 ng) cholesterol per well, which is 100-fold more sensitive than published fluorometric and colorimetric methods. When applied to the measurement of cholesterol levels in serum and food samples, the Amplex Red-based method has been found more attractive since the oxidation product of the Amplex Red method has superior long wavelength spectra which are less susceptible to interference from the biological compounds.     

A rapid and sensitive method for HPLC cholesterol determination in bile.

A relatively little time consuming simple method based on the treatment of bile with cholesterol oxidase and subsequent high performance liquid chromatography measurement of the 3-ketocholesterol produced in order to determine the level of the cholesterol concentration is described. The method avoids bilirubin interferences, has high reproducibility and recovery assays give 100% values. It is highly sensitive and suitable for use in the determination of cholesterol concentrations in bile and other bilirubin containing biological fluids.     

A sensitive method for determination of cholesterol growth using model solutions of supersaturated bile

We describe a novel, facile, and highly reproducible spectrophotometric technique to measure a cholesterol crystal growth curve. This method permits a quantitative estimate of the potency or comparative abundance of a given kinetic effector substance. In addition to several internal validation procedures, data are provided that support the usefulness of the technique in the assay of substances with either known promoting activity, i.e., human mucin glycoprotein, or those with known inhibitory activity, i.e., human apolipoprotein A-I.