RESUMO
The article describes the development and evaluation of the alkaline haematin detergent (AHD575) method for the determination of haemoglobin in blood without the need for toxic materials and suitable for use in laboratories in countries with limited resources and restricted import of toxic materials. The validation of the method has been performed in accordance with the requirements set out in the international standard ISO 15193, which describes the procedures necessary for development of a candidate reference measure-ment procedure. The main results were: The trueness of the haemiglobin cyanide (HiCN) method depends upon the diluent used. The international haemiglobin cyanide reference material BCR CRM 522 does not have the same chemical properties as that derived from fresh lysed erythrocytes and cannot be used for calibrating the AHD575 method. The transformation of oxyhaemoglobin to haematin at pH 13 proceeds 5-8 times more rapidly than its conversion to haemiglobin cyanide. The AHD575 method yields results comparable with the HiCN method and uses a readily available crystalline standard of high purity. The introduction of the AHD575 method does not require new reference intervals, the values being directly transferable from (commutable with) the established HiCN procedure.
