Recovery of glycerolized red blood cells frozen in liquid nitrogen.

Abstract

Human red blood cells were frozen at a rapid rate in the presence of approximately 20 per cent w/v glycerol and an osmotic supporting agent, and were stored in liquid nitrogen vapor at approximately — 150 C for at least two weeks before thawing, washing, and resuspension. The recovery of red blood cells upon thawing was dependent on the type of freezing container used and the volume of red blood cells frozen. An additional loss of red blood cells during postthaw washing was related to the volume of red blood cells frozen, but was not related to the type of osmotic supporting agent used during the wash. The total amount of supernatant hemoglobin in the washed unit was inversely related to the recovery of the red blood cells upon thawing. For adequate recovery of preserved red blood cells, both the geometry of the container in which the cells had been frozen, and the capacity of the reusable bowl‐washing system employed for removing the glycerol, limited the mass of glycerolized red blood cells to less than 600 g.