Send to

Choose Destination
Clin Chem. 1995 May;41(5):717-23.

Direct measurement of high-density lipoprotein cholesterol in serum with polyethylene glycol-modified enzymes and sulfated alpha-cyclodextrin.

Author information

Department of Laboratory Medicine, Kumamoto University Medical School, Japan.


We have developed an automated method for measuring high-density lipoprotein (HDL)-cholesterol in serum without prior separation, using polyethylene glycol (PEG)-modified enzymes and sulfated alpha-cyclodextrin. When cholesterol esterase and cholesterol oxidase enzymes were modified with PEG, they showed selective catalytic activities towards lipoprotein fractions, with the reactivity increasing in the order: low-density lipoprotein < very-low-density lipoprotein approximately chylomicron < HDL. In the presence of magnesium ions, alpha-cyclodextrin sulfate reduced the reactivity of cholesterol, especially in chylomicrons and very-low-density lipoprotein, without the need for precipitation of those lipoprotein fractions. The combination of PEG-modified enzymes with alpha-cyclodextrin sulfate provided selectivity for the determination of HDL-cholesterol in serum in the presence of a small amount of dextran sulfate without the need for precipitation of lipoprotein aggregates. The results of the HDL-cholesterol assayed in serum by this direct method correlated well with those obtained by precipitation-based methods and also that by an ultracentrifugation method.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center