Quantification of free and bound pantothenic acid in foods and blood plasma by a stable isotope dilution assay.
A stable isotope dilution assay for quantification of pantothenic acid in food and blood plasma uses a 4-fold labeled isotopomer of the vitamin as an internal standard. Pantothenic acid and its labeled analogue were detected as trimethylsilyl derivatives by gas chromatography-mass spectrometry, showing a minimized spectral overlap. In starch a detection limit of 44 microg/kg, an intrasample relative standard deviation of 6.7%, and recovery values ranging between 97.5 and 99.4% were determined. Total pantothenic acid content was determined in rice, milk powder, apple juice, and blood plasma after enzymatic hydrolysis of the vitamin's conjugates; free pantothenic acid was quantified prior to enzyme treatment. Almost all results were found to be in good agreement with literature data.
Rychlik
M
M
Institut für Lebensmittelchemie der Technischen Universität München, Lichtenbergstr. 4, D-85748 Garching, Germany. michaelr@leb.chemie.tu-muenchen.de
D002247:Carbon Isotopes; D005504:Food Analysis; D006801:Humans; D007553:Isotope Labeling / Q000379:methods; D013058:Mass Spectrometry / Q000379:methods; D009587:Nitrogen Isotopes; D010205:Pantothenic Acid / Q000032:analysis* / Q000097:blood; D015091:beta-Alanine / Q000032:analysis
D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D015091:beta-Alanine; D010205:Pantothenic Acid