Liquid chromatography-tandem mass spectrometry determination of plasma 24S-hydroxycholesterol with chromatographic separation of 25-hydroxycholesterol.
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ABSTRACT:
SUBMITTER: DeBarber AE
PROVIDER: S-EPMC2562163 | biostudies-literature | 2008 Oct
REPOSITORIES: biostudies-literature
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Liquid chromatography-tandem mass spectrometry determination of plasma 24S-hydroxycholesterol with chromatographic separation of 25-hydroxycholesterol.
DeBarber Andrea E AE Lütjohann Dieter D Merkens Louise L Steiner Robert D RD
Analytical biochemistry 20080613 1
Concentrations of circulating 24S-hydroxycholesterol (24SOHChol) are of interest as a practical measure of cholesterol efflux from the human brain. The current method of choice for 24SOHChol quantification is with gas chromatography-mass spectrometry (GC-MS). Liquid chromatography-mass spectrometry (LC-MS) methods to detect 24SOHChol have been described, but they lack rigorous high-performance liquid chromatography (HPLC) separation of a closely eluting isomeric oxysterol, 25-hydroxycholesterol. ...[more]
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