Premium
Measurement of deuterium‐labeled phylloquinone in plasma by LC‐APCI‐MS
Author(s) -
Fu Xueyan,
Dolnikowski Gregory,
Peterson James,
Booth Sarah L
Publication year - 2009
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.23.1_supplement.566.1
Subject(s) - chemistry , atmospheric pressure chemical ionization , chromatography , mass spectrometry , liquid chromatography–mass spectrometry , sample preparation , high performance liquid chromatography , analytical chemistry (journal) , chemical ionization , ionization , ion , organic chemistry
Deuterium‐labeled vegetables were fed to humans for the measurement of both unlabeled and deuterium‐labeled phylloquinone in plasma. We developed a technique to determine the quantities of these compounds using liquid chromatography/mass spectrometry with atmospheric pressure chemical ionization (LC‐APCI‐MS). Sample preparation involved liquid‐liquid and solid‐phrase extraction techniques. The internal standard (K 1(25) ) was used to quantify both unlabeled and labeled phylloquinone. The standard calibration curve had a linear correlation coefficient (R 2 ) of 0.998 and 0.999 for unlabeled and labeled phylloquinone, respectively. The minimal detectable concentration of unlabeled and labeled phylloquinone was 0.05 and 0.08 pmol/injection. For pooled plasma samples spiked with 0.5 to 32 nmol phylloquinone/L, average recoveries were 95 +/‐ 4.0 % for unlabeled phylloquinone and 96 +/‐ 7.9 % for labeled phylloquinone. The phylloquinone concentrations determined by LC‐ fluorescence and LC‐APCI‐MS methods from healthy subjects (n=20) were correlated (R 2 =0.983, P =0.053). This new method allows us to measure labeled phylloquinone concentrations in healthy subjects (n=3) in response to ingesting deuterium‐labeled food. The LC‐APCI‐MS method is a sensitive and accurate technique for determination of both labeled and unlabeled phylloquinone, and can be applied to bioavailability studies.