The effect of albumin on osmotic hemolysis

Abstract

The effect of albumin on osmotic hemolysis was studied by placing human erythrocytes in hypotonic salt solutions containing albumin. The degree of hemolysis that occurred was measured spectrophotometrically. It was found that the extent of hemolysis in the solutions at a given pH and osmolarity diminished with increasing albumin concentrations. 50 per cent hemolysis occurred in about 9 per cent albumin solutions. Varying the osmolarity between 60 and 127 milliosmoles did not affect the degree of hemolysis at a given pH and albumin concentration. Varying the pH with the albumin concentration and osmolarity held constant did not affect the degree of hemolysis between pH 7.0 and 5.7. Below 5.7, the degree of hemolysis increased with decreasing pH. The results can be explained in terms of the colloid-osmotic theory of osmotic hemolysis. The erythrocyte in hypotonic albumin solutions becomes permeable to cations. If the osmotic pressure of the albumin in the solution balances that of the hemoglobin in the cell, no hemolysis occurs. If the osmotic pressure of the albumin is less than that of the hemoglobin, partial hemolysis ensues until the osmotic pressures of the albumin plus hemoglobin outside of the cell balance that of the remaining hemoglobin in the cell.