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Haemoglobin estimation by the cyan haematin method

1949; Oxford University Press; Volume: 43; Issue: 1 Linguagem: Inglês

10.1016/0035-9203(49)90025-5

1878-3503

Helmar C. Lehmann, Rodger B. Baird,

Hemoglobinopathies and Related Disorders

The cyan haematin method for the estimation of haemoglobin concentration in blood—performed at the high temperatures experienced in a tropical climate—yields higher results than the alkaline haematin method. This difference is greater the higher the temperature at which the blood is incubated with 0·1 N HC1 to form acid haematin prior to its conversion into cyan haematin. It is suggested that this difference is due to a partial denaturation of the histon globin when incubated in 0·1 N HC1 in the presence of the non-haemoglobin constituents of the red cells—leading to a turbidity on the addition of cyanide. This turbidity can be lessened by cooling the acid haematin solution before the cyanide is added to form cyan haematin. It can also be avoided by lowering the temperature at which the acid haematin is formed, or by the addition of salt, or by transforming the acid haematin into alkaline haematin before the addition of cyanide. The best procedures to use are incubation with either 0·033 N HCI or 0·033 N NaOH to form the haematin before its conversion into cyan haematin without any other alteration of the original method. The results thus obtained correspond closely to those arrived at by the alkaline haematin method of Clegg and King (1942).