Improved method for simultaneous determination of ascorbic acid and dehydroascorbic acid, isoascorbic acid and dehydroisoascorbic acid in food and biological samples

J Chromatogr B Biomed Sci Appl. 1999 Jun 25;730(1):101-11. doi: 10.1016/s0378-4347(99)00193-0.


The total vitamin C amount in different food and plasma samples was determined by a dual detection system, after HPLC separation, with direct detection of ascorbic acid and indirect fluorimetric detection of dehydroascorbic acid after a post-column O-phenyldiamine derivatisation. The two active forms of vitamin C and their D-isomers were separated within 10 min. The repeatability was determined by measurement of several fruits and vegetables and ranged from 0.3 to 1.9% (relative standard deviation) for vitamin C. The reproducibility, based on double determinations, ranged from 1.9 to 3.6% for vitamin C, depending on the matrix. The reproducibility, based on several determinations of reference materials, ranged from 2.4 to 3.7% for ascorbic acid and from 4.3 to 5.8% for dehydroascorbic acid, again depending on the matrix.

MeSH terms

  • Ascorbic Acid / analogs & derivatives
  • Ascorbic Acid / analysis*
  • Ascorbic Acid / blood
  • Chromatography, High Pressure Liquid / methods*
  • Food Analysis*
  • Humans
  • Reference Standards
  • Reproducibility of Results
  • Spectrometry, Fluorescence
  • Vegetables / chemistry*


  • Ascorbic Acid