Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1996-3-8
pubmed:abstractText
A simple and rapid method for the quantitation of total cholesterol in lipid extracts using gas-liquid chromatography is presented here as a modification of an earlier saponification procedure (Ishikawa, T. T., J. MacGee, J. A. Morrison, and C. J. Glueck. 1974. Quantitative analysis of cholesterol in 5 to 20 microliters of plasma. J. Lipid Res. 15: 286-291). Using the original method, as well as a slightly modified version, we found a systematic loss of cholesterol measured as total cholesterol that was attributable to the formation of a byproduct during the procedure. Depending on the nature of the solvent mixture used for extraction after saponification, different byproducts were produced that had longer retention times than cholesterol. The byproducts were identified as cholesteryl butyrate (produced when methyl butyrate was included in the solvent mix) and cholesteryl propionate (with ethyl propionate in the solvent mix) by comparison to authentic standards using gas chromatography-mass spectroscopy. Using mixtures of cholesterol standards, we compared several solvents in lieu of the solvent mixture used in the original extraction procedure to identify those that eliminate the formation of the byproducts. Our optimized microsaponification procedure uses a single solvent, tetrachloroethylene, to extract lipids after the saponification reaction, and improves the accuracy of the cholesterol determination.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-2275
pubmed:author
pubmed:issnType
Print
pubmed:volume
36
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2261-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Cholesterol quantitation by GLC: artifactual formation of short-chain steryl esters.
pubmed:affiliation
Department of Biochemistry, Medical College of Pennsylvania, Philadelphia 19129, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't