Premium
Determination of serum cortisol by thermospray liquid chromatography/mass spectrometry: Comparison with gas chromatography/mass spectrometry
Author(s) -
Gaskell Simon J.,
Rollins Keith,
Smith Richard W.,
Parker Carol E.
Publication year - 1987
Publication title -
biomedical and environmental mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.475
H-Index - 121
eISSN - 1096-9888
pISSN - 0887-6134
DOI - 10.1002/bms.1200141205
Subject(s) - thermospray , chromatography , chemistry , mass spectrometry , isotope dilution , gas chromatography–mass spectrometry , gas chromatography , liquid chromatography–mass spectrometry , reproducibility , tandem mass spectrometry , selected reaction monitoring
The determination of serum cortisol by thermospray liquid chromatography/mass spectrometry (LC/MS) has been assessed. The method incorporates stable isotope dilution and innumoadsorption extraction. [M + H] + ions are monitored during LC/MS. The within‐assay reproducibility is satisfactory (coefficient of variation 7% at a concentration of 190 ng ml −1 ), though inferior to that achieved with the (more lengthy) procedure of gas chromatography/mass spectrometry (GC/MS). Satisfactory agreement between LC/MS ( y ) and GC/MS ( x ) data was observed ( y = 0.934 x + 12.4 ng ml −1 ; r = 0.968; n = 14). It is concluded that the generation of precise reference data for the assessment of routine cortisol assays is at present better achieved by GC/MS. LC/MS, however, provides satisfactory quantitative data via a more simple and rapid method.