MICRO LIQUID-CHROMATOGRAPHY MASS-SPECTROMETRY WITH DIRECT LIQUID INTRODUCTION USED FOR SEPARATION AND QUANTITATION OF ALL-TRANS-RETINOIC AND 13-CIS-RETINOIC ACIDS AND THEIR 4-OXO METABOLITES IN HUMAN PLASMA
Ub. Ranalder et al., MICRO LIQUID-CHROMATOGRAPHY MASS-SPECTROMETRY WITH DIRECT LIQUID INTRODUCTION USED FOR SEPARATION AND QUANTITATION OF ALL-TRANS-RETINOIC AND 13-CIS-RETINOIC ACIDS AND THEIR 4-OXO METABOLITES IN HUMAN PLASMA, Journal of chromatography. Biomedical applications, 617(1), 1993, pp. 129-135
The separation and quantitation of the pentafluorobenzyl derivatives o
f all-trans- and 13-cis-retinoic acids and their 4-oxo metabolites in
human plasma on micro high-performance liquid chromatographic columns
(0.32 mm I.D.) is described. The column outlet was directly coupled to
the source of a quadrupole mass spectrometer via a simple SFC-frit in
terface. Negative ion chemical ionization conditions were obtained by
coaxial introduction of ammonia as a reagent gas. A signal-to-noise ra
tio well above 3 was obtained for 1 pg of each analyte injected. The l
imit of quantitation calculated from spiked biological plasma extracts
was 0.3 ng/ml.