Rapid quantification of free and esterified phytosterols in human serum using APPI-LC-MS/MS.
A novel analytical platform based on liquid chromatography and tandem mass spectrometry using atmospheric pressure photoionization was applied for the simultaneous quantification of free and esterified beta-sitosterol, campesterol, brassicasterol, and stigmasterol. The total time for sample pretreatment and analysis could be reduced from approximately 3 h [gas chromatography-mass spectrometry (GC-MS)] to 15 min. The detection limits of the different phytosterols ranged between 0.25 and 0.68 microg/l. Linear ranges were between 1 and 1,000 microg/l. The within-run and between-run variabilities ranged between 1.4% and 9.9%. The analytical sensitivity was at least 150-fold higher compared with GC-MS. Our new method allows a rapid and simultaneous determination of free and esterified phytosterols in serum.
Institute of Laboratory Medicine, Clinical Chemistry, and Molecular Diagnostics, University Hospital, Leipzig, Germany.
Jan
J
Lembcke
Uta
U
Ceglarek
Georg Martin
GM
Fiedler
Sven
S
Baumann
Alexander
A
Leichtle
Joachim
J
Thiery
D002775:Cholestadienols / Q000097:blood; D002784:Cholesterol / Q000031:analogs & derivatives* / Q000097:blood; D002853:Chromatography, Liquid; D004952:Esters / Q000097:blood; D006801:Humans; D013058:Mass Spectrometry / Q000295:instrumentation / Q000379:methods*; D008722:Methods; D010840:Phytosterols / Q000097:blood*; D015203:Reproducibility of Results; D012855:Sitosterols / Q000097:blood; D013265:Stigmasterol / Q000097:blood
D002775:Cholestadienols; D004952:Esters; D010840:Phytosterols; D012855:Sitosterols; C003532:brassicasterol; C021273:campesterol; C025473:gamma-sitosterol; D002784:Cholesterol; D013265:Stigmasterol