Intraerythrocyte pH and Physiochemical Homogeneity

Abstract

To determine the physicochemical homogeneity of the human red cell, intraerythrocyte pH was simultaneously measured using the weak acid 5,5-dimethyloxazolidine-2,4-dione (DMO) and the weak base nicotine. If a cell is homogeneous, such measurements will yield the same result. If a cell is heterogeneous, the DMO reading will be closer to the highest pH in the cell system, while the nicotine will read closer to the lowest pH. No significant difference was shown between the intracellular pH obtained by either method (average by DMO = 7.10, by nicotine = 7.06 at an average external pH of 7.33). The human erythrocyte is physiochemically homogeneous.