Skip to content
Licensed Unlicensed Requires Authentication Published by De Gruyter June 1, 2005

An International Standard for whole blood folate: evaluation of a lyophilised haemolysate in an international collaborative study

  • Susan J. Thorpe , Dawn Sands , Alan B. Heath , Malcolm S. Hamilton , Sheena Blackmore and Trevor Barrowcliffe

Abstract

Folate measurements, particularly for whole blood, show wide inter-laboratory and inter-methodology variability. This variability appears to be due in part to the lack of internationally accepted reference materials. A whole blood haemolysate, lyophilised in ampoules and designated 95/528, was therefore evaluated by 15 laboratories in five countries for its suitability as an International Standard (IS) for whole blood folate. The preparation was assayed using a variety of microbiological and protein-binding methodologies against local standards and calibrators. A consensus folate content was assigned to 95/528. The inclusion of three whole blood samples in the study with widely differing folate levels demonstrated a considerable reduction in inter-laboratory variability when the folate content of the samples was determined relative to the proposed IS 95/528 rather than to laboratories' local standards and calibrators. Accelerated degradation studies indicated that the folate content of 95/528 is stable when stored at −20°C. On the basis of the results presented here, the World Health Organization Expert Committee on Biological Standardization established 95/528 as an IS for whole blood folate.

Published Online: 2005-6-1
Published in Print: 2004-5-10

Copyright © 2004 by Walter de Gruyter GmbH & Co. KG

Downloaded on 29.3.2024 from https://www.degruyter.com/document/doi/10.1515/CCLM.2004.090/html
Scroll to top button