Serum ascorbic acid stability over an extended period : Relevance to epidemiological studies.
Epidemiological evidence suggests that intake of vitamin C and of fruit and vegetables rich in vitamin C may reduce the risk of certain cancers.
Most epidemiological studies have relied on estimates of vitamin C based on questionnaires because serum ascorbic acid (AA) can be very unstable.
The objective of this study was to investigate the effect of extended storage at - 70°C and of multiple free-thaws on AA concentration in stabilized human serum from a large multi-center cervical cancer case-control study ; the serum samples had been stabilized by acidification with meta-phosphoric acid and stored at - 70°C. The results showed that under these conditions human serum samples are stable for periods of at least 2 years.
There were indications that sample preparation in the field and freezing and thawing the stabilized serum samples could affect reproducibility and validity.
Overall, our results indicate that with this stabilization method, biological material collected in large-scale, multicenter studies remains useful for AA analysis for at least 2 years after collection.
Mots-clés Pascal : Epidémiologie, Acide ascorbique, Essai basse température, Conservation échantillon, Plasma sanguin, Stabilité, Alimentation, Etat nutritionnel, Vitamine, Facteur milieu, Homme
Mots-clés Pascal anglais : Epidemiology, Ascorbic acid, Low temperature test, Sample conservation, Blood plasma, Stability, Feeding, Nutritional status, Vitamin, Environmental factor, Human
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 98-0450182
Code Inist : 002B30A01A1. Création : 25/01/1999.