title: High-density lipoproteins estimated by an enzymatic cholesterol procedure, with a centrifugal analyzer.
abstract: We describe an assay for high-density lipoprotein cholesterol, adapted to a centrifugal analyzer, the GEMSAEC System 3, which includes use of an increased Mn2+concentration (91 mmol/liter) [J. Lipid Res. 19, 65 (1978)] and ethylenediaminetetraacetate [Clin. Chem. 22, 98 (1976)]. Modifications to the GEMSAEC system include reducing the mixing burst and preconditioning the sample tip. Accuracy of this procedure, as assessed by analysis of a control pool from the Center for Disease Control, was 99.2%. Day-to-day precision for two control pools was 320 +/- 13 and 506 +/- 17 mg/liter. Serum sample volume was decreased to 0.5 ml. In blanks with heparin/Mn2+ present, the pseudocholesterol concentrations resulting from a reaction of the enzymatic cholesterol reagent and the heparin/Mn2+ precipitating reagent depend on the source of the enzymatic reagent and appear to be enhanced slightly by the use of ethylenediaminetetraacetate. Pseudocholesterol concentrations reach a maximum at heparin/Mn2+ concentrations well below those needed to completely precipitate the low-density and very-low-density lipoprotein fractions. Population reference values were obtained from analyses done on 224 local physicians (mean: male, 500 mg/liter; female, 620 mg/liter) and 156 ambulatory patients (mean: male, 463 mg/liter; female, 553 mg/liter).
mesh_terms: D001322:Autoanalysis; D002498:Centrifugation / Q000379:methods; D002784:Cholesterol / Q000097:blood*; D006493:Heparin; D006801:Humans; D008075:Lipoproteins, HDL / Q000097:blood*; D008345:Manganese
chemical_list: D008075:Lipoproteins, HDL; D008345:Manganese; D006493:Heparin; D002784:Cholesterol