Stability of whole blood and plasma ascorbic acid

• Published in: European journal of clinical nutrition 2007-10, Vol.61 (10), p.1233-1236
• Main Authors: Karlsen, A, Blomhoff, R, Gundersen, T.E
• Format: Article
• Language: English
• Subjects: Acidification; Anticoagulants; Anticoagulants - administration & dosage; Antioxidants - analysis; Antioxidants - metabolism; Ascorbic acid; Ascorbic Acid - analysis; Ascorbic Acid - blood; Biological and medical sciences; Biological properties; Biological samples; Blood; blood chemistry; blood plasma; Blood Preservation - methods; blood sampling; Blood Specimen Collection - methods; Blood tests; Centrifugation; chemical degradation; Chromatography, High Pressure Liquid - methods; Citric acid; Clinical Nutrition; Cryopreservation - methods; Drug Stability; EDTA (chelating agent); Epidemiology; Ethylenediaminetetraacetic acids; Handling; Heparin; Heparin - administration & dosage; High-performance liquid chromatography; Humans; Hydrogen-Ion Concentration; Initial conditions; Internal Medicine; Liquid chromatography; Medical sciences; Medicine; Medicine & Public Health; Metabolic Diseases; Nutrition; Plasma; Public Health; short-communication; stability; Stability analysis; Stabilyte; Storage; Storage temperature; storage time; Temperature; temporal variation; Time Factors; Tubes; Vitamin C
• ISSN: 0954-3007; 1476-5640
• DOI: 10.1038/sj.ejcn.1602655

The objective of this study was to evaluate the impact of pre-analytical factors on the short and long term stability of ascorbic acid (AA), the main form of vitamin C in whole blood and plasma. The effects of various anticoagulants, acidification, storage temperature and time were tested. A recently developed fast and sensitive HPLC method was used to measure AA levels. AA baseline values observed in heparin plasma were significantly higher than values observed in EDTA, citrate and Stabilyte plasma, as well as in serum. pH and temperature were identified as additional critical pre-analytical factors during the short, medium and long term handling and storage. Thus, assessment of reliable and accurate AA status in biological samples demonstrates to be highly dependent on whether the initial conditions during sample handling are controlled. In conclusion, heparin tubes should be used for blood sample collection. As AA is rapidly degraded, sample collection should be followed by immediate centrifugation and plasma acidification. To avoid further degradation during sample handling, samples should be stored at -70°C without delay and analyzed within 80 days.