FRACTIONATION OF IRRADIATED CHOLESTEROL

Fractionation of serum cholesterol: a critique.

A procedure for fractionation of serum cholesterol is developed by employing digitonin for the precipitation of free cholesterol in isopropanol. This method is based on the ferric acetate color reaction which is unaffected by traces of digitonin. It is influenced only negligibly by the presence of stanols in serum and is shown to be equally chromogenic with respect to both free and ester forms ...

The Antirachitic Value of Irradiated Cholesterol

As is well known, young rats can be regularly protected from rickets by the addition to their dietary of 1 mg. or less of irradiated cholesterol. Various experiences led us to believe that this cholesterol was a mixture of active and inactive material and that an attempt should, therefore, be made to fractionate it. In the first place prolonged irradiation gradually inactivates cholesterol whic...

Cholesterol determination in serum after fractionation of lipoproteins by immunoprecipitation.

We investigated the immunoprecipitation of apolipoprotein B-binding lipoproteins, or of apo A-I- and apo C-binding lipoproteins, by delipidated antiserum for measuring cholesterol in the nonprecipitated lipoprotein fractions. After immunoprecipitation of serum with delipidated anti-apo B, we determined by immunoelectrophoresis that no beta- or pre-beta lipoproteins were present, whereas alpha-l...

The fractionation of cholesterol esters by silicic acid chromatography.

Within recent years, the technique of silicic acid chromatography to separate complex mixtures of lipides has been developed widely (1-3). At the present time it is possible to resolve some eight different classes of lipides ranging from hydrocarbons to phospholipides on a single column (4). In addition, this procedure has been used to separate classes of phospholipides from one another (5). Ou...

Fractionation of Cholesterol Esters by Thin-layer Chromatography.