A Method for Routine Assay of Plasma Ascorbic Acid Using High-Performance Liquid Chromatography

Abstract

A description is given of a specific and simple liquid chromatographic method for the determination of vitamin C (ascorbic acid) in protein-free plasma. The analysis time per sample is only 4 min, the retention time of ascorbic acid being 2.4 min. A detection limit of 0.3 mg/l (1.7 μmol/l) was achieved using the routine attenuation of the detector. The day-to-day coefficient of variation is less than 7.2% at a physiological level and the within-day variation is less than 4.7%. The method recovered 101% (mean) of ascorbic acid supplemented to plasma. Mean plasma ascorbic acid concentration was 11.1 mg/l (63 μmol/l) in healthy adult volunteers, whereas considerably lower values were found in a group of randomly selected 54-year-old-men.