Albumin can reverse the release of potassium from human erythrocytes treated with the non-ionic detergent, Brij 58.

Exchange of erythrocyte intracellular (i/c) K+ for extracellular (e/c) Na+ in human erythrocytes treated with sub-CMC concentrations of the non-ionic detergent Brij 58 can be stopped by reincubation in serum or albumin containing solutions. The progressive equilibration of the K+ contents of detergent-treated human erythrocytes with the incubation medium was reversed by an albumin-mediated withdrawal of detergent molecules from the cell. Re-establishment of near normal [K+] in terms of K+/kg water proceeds in two ways: (i) a metabolism-dependent net accumulation of K+ ions; and (ii) a metabolism-independent shrinkage of erythrocytes, this being the more significant factor.