Stability of haemiglobincyanide standards

摘要

This journal published the first recommendations and requirements for haemoglobinometry in human blood by the International Committee for Standardization in Haematology of the European Society of Haematology in 1965. The recommendations were discussed further and adopted at the world level during the Xlth International Congress of Haematology in 1966 and have since been reviewed and modified on the basis of continued experimental studies; the latest revision can be found on p 271. The recommended reference method for the determination of the haemoglobin concentration in blood is spectrophotometric measurement after conversion of haemoglobin to haemiglobincyanide (HiCN) (cyanmethomo-globin, CNmetHb). The measuring instrument should be checked as to absorbance with HiCN standards. The Dutch National Institute for Public Health (and Environmental Protection) (RIV (M)) prepared HiCN solutions for distribution as a reference standard for haemoglobinometry in 1961 and offered such a solution to ICSH as candidate international HiCN reference preparation in 1963. ICSH issued the first international HiCN reference solution in 1966 and the World Health Organisation (WHO) established such solutions as the international HiCN reference preparation in 1968. RIV has continued to produce the international HiCN reference preparations, now international HiCN standards, through 1987 and the WHO has accepted subsequent preparations as the second, third, etc., international standard. New standards were originally produced every year, checked for nine to 12 months, then issued for a period of two years. This ensured that, should a solution suddenly deteriorate, a second standard would be available for distribution. International HiCN standards are used to assign values to secondary HiCN reference solutions, and as a reference against which to judge the purity of such HiCN solutions. As stability data on these standards, stored at 4℃, in the dark, accumulated, it was decided in 1979 to go to a three year production cycle and to issue the standards with a six year expiration date. This report summarises measurement data of international HiCN standards stored at 4℃, in the dark, for up to 27 years.