Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1984-7-9
pubmed:abstractText
An analytical method for the quantitation of nanogram to subnanogram amounts of dexamethasone is described. Dexamethasone was isolated from human plasma using a C18-bonded reverse-phase cartridge, purified by subsequent normal-phase HPLC, and the corresponding trimethylsilyl derivative analyzed by gas chromatography-mass spectrometry (GC-MS). The quantitation by isotope-dilution MS was carried out by selected-ion monitoring on the (M + 1)+ ion of the trimethylsilyl derivative of dexamethasone and its stable isotopically labeled diluent, [ 13C6 ,2H3]dexamethasone (681 and 690 m/z, respectively). Methane was used as the GC carrier gas and as the chemical-ionization reagent gas. The sensitivity of the method, judged from the lower limit of detection of the mass spectrometer, was at approximately 100 pg. The inter- and intraassay coefficients of variation (CV) determined at two different concentrations were 3.83 and 3.78% for 2 ng/mL and 2.64 and 1.29% for 5 ng/mL, respectively. Plasma concentration profiles for dexamethasone following a single 1-mg iv and a 2-mg oral dose of dexamethasone administered 24 h apart to two healthy volunteers are presented. The mass fragmentographic method described here is useful for bioavailability and pharmacokinetic studies of the synthetic glucocorticoid.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-3549
pubmed:author
pubmed:issnType
Print
pubmed:volume
73
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
446-51
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Quantitative determination of dexamethasone in human plasma by stable isotope dilution mass spectrometry.
pubmed:publicationType
Journal Article