Linked Life Data

11055721

Source:http://linkedlifedata.com/resource/pubmed/id/11055721

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
2000-11-7
pubmed:abstractText
A method based on high-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (APCI LC-MS) was developed for the quantification of the bioavailability of retinyl palmitate and beta-carotene and the bioconversion of beta-carotene to retinol in humans. Following oral administration of [8,9,10,11,12,13,14,15,19,20-13C10]-retinyl palmitate and [12,13,14,15,20,12',13',14',15',20'-13C10]-beta-carotene at physiological doses to children between 8 and 11 years of age, blood samples were drawn and serum was prepared. Retinol and beta-carotene were extracted from 0.2- and 1.0-mL serum samples, respectively, and analyzed using reversed-phase HPLC with a C30 column interfaced to an APCI mass spectrometer. Unlike other LC-MS assays for carotenoids, no additional purification steps were necessary, nor was any derivatization of retinol or beta-carotene required. APCI LC-MS showed a linear detector response for beta-carotene over 4 orders of magnitude. Using selected ion monitoring to record the elution profile of protonated circulating beta-carotene at m/z 537 and [13C10]-beta-carotene at m/z 547, the limit of detection was determined to be 0.5 pmol injected on-column. To assess the ratio of labeled to unlabeled retinol, selected ion monitoring was carried out at m/z 269, 274, and 279. These abundant fragment ions corresponded to the loss of water from the protonated molecule of circulating retinol, [13C5]-retinol (metabolically formed from orally administered [13C10]-beta-carotene), and [13C10]-retinol (formed by hydrolysis of [13C10]-retinyl palmitate). The ratios of labeled to unlabeled retinol and the ratio of labeled to unlabeled beta-carotene were calculated. Combined with standard HPLC measurement of beta-carotene and retinol concentration and a mathematical model, these results showed that this simple LC-MS method can be used to quantify beta-carotene bioavailability and its bioconversion to retinol at physiologically relevant doses.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0003-2700
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
72
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4999-5003
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
A liquid chromatography-mass spectrometry method for the quantification of bioavailability and bioconversion of beta-carotene to retinol in humans.
pubmed:affiliation
Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 60612, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.