Liquid Nitrogen Storage of Haemoglobin Variants.

Received for publication 26 April 1963. is thawed immediately after freezing a precipitate of denatured protein can be seen in the solution. We have recently been investigating the storage of human red cells in liquid nitrogen for serological purposes (Huntsman, Hum, Ikin, Lehmann, and Liddell, 1962). We thought that this technique might be useful for the preservation of haemoglobin as well as for that of the red cell agglutinins. We have therefore stored in liquid nitrogen, cells and haemoglobin solutions containing haemoglobins A+S, A+H (+ trace of Bart's), A+G,Norfolk, A+Dopunjab as well as normal samples containing only haemoglobin A and haemoglobin A2. AIl these samples were stored for six months, both in a liquid nitrogen refrigerator at 196°C. and in the conventional deep freeze cabinet at -20°C. The cells were frozen both as packed red cells and as whole blood containing 13% sucrose. The haemoglobin A+H solution which had been stored at 196°C. showed no precipitation while the subsequent electrophoresis (shown in the figures) was satisfactory. The red cells containing haemoglobin H after similar storage showed no inclusion bodies after