A combination of treating outdated packed red blood cells (PRBCs) with carbontetrachloride, countercurrent dialysis and modified conditions of freeze-drying served to improve and standardize the technology of "stroma-free hemolysate" (SFH) in our laboratory. As a rule, proteins of the final product corresponded to 95% oxyhemoglobin, 3.5% methemoglobin and 1.5% non-hemoglobin ones. In freeze-dried samples stabilized with 0.24 molar saccharides, the weight proportions were 56% hemoglobin, 44% sucrose and/or 62% hemoglobin, and 38% fructose, respectively. If necessary, the saccharides could be rapidly removed from the easily reconstituted SFH by dialysis or chromatography. Analytical parameters were similar to those of chloroform-treated SFH stored dry at -12 degrees C for 4 months. However, the present procedure was easier and SFH samples remained unchanged after dry storage even at +4 degrees C for at least 13 months. This oxyhemoglobin product seems suitable for organ perfusion, further chemical modification and as an analytical standard.

Institute of Hematology and Blood Transfusion Prague Czechoslovakia