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PubMed · 189954

Beta-lipoprotein cholesterol quantitation with polycations.

C C Heuck·G Schlierf
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Abstract

We compared direct determination of beta-lipoprotein cholesterol after selective extraction of very-low-density and high-density lipoproteins from serum with poly(ethyleneimine) and a cation-exchange resin with the classical quantitation after lipoprotein fractionation with the ultracentrifuge. At beta-lipoprotein cholesterol concentrations between 1.50 and 5.00 g/liter the correlation is linear (r = 0.95). The precision for the extraction procedure is as good (CV 2.4-2.8%) as for the quantitation by ultracentrifugation (CV 3.2-6.0%). From solutions of isolated lipoproteins, very-low-density lipoproteins are 93% extracted and high-density lipoproteins 60%, but low-density-lipoproteins only 5%. The molecular mechanism of the extraction is supposed to be due to both hydrophobic interaction of long-chain fatty acid residues and ionic interaction of phospholipids located at the surface of very low-density and high-density lipoproteins and the lipophilic polycation.

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CholesterolHumansHyperlipidemiasIon Exchange ResinsLipoproteinsLipoproteins, LDLPolyethyleneiminePolyethylenesSerum Albumin, BovineTriglyceridesUltracentrifugationComparative StudyJournal Article

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C C Heuck, G Schlierf. 1977. Beta-lipoprotein cholesterol quantitation with polycations.. https://pubmed.ncbi.nlm.nih.gov/189954/

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