Cryoprotective additives and hypertonic hemolysis

Abstract The effects of three cryoprotective additives, dimethyl sulfoxide, sucrose and polyvinylpyrrolidone, on hemolysis of human red cells in hypertonic solutions of sodium chloride have been examined at room temperature. At the mole fractions of sodium chloride studied, polyvinylpyrrolidone reduced the level of hypertonic hemolysis; dimethyl sulfoxide and sucrose had no effect. This suggests that the cryoprotective properties of polyvinylpyrrolidone may be due not only to its ability to reduce salt concentration during freezing but also to some reduction in colloid osmotic swelling.