The electrophoretic behavior of human erythrocyte is investigated theoretically. The present analysis extends previous studies to that the effect of the membrane structure of a cell is taken into account. The result obtained provides a useful tool for the estimation of the surface properties of human erythrocyte through electrophoretic measurements. Fitting the present model to the experimental data of Haydon and Seaman [Arch. Biochem. Biophys. 122 (1967) 126], for example, reveals that the surface charge of erythrocyte arises mainly from the dissociation of three functional groups, which bond to different sites on cell membrane : (a) N-acetylneuraminic acid (sialic acid) with pKHANaa=2.6, (b) some kind of α-carboxylic acid with pKHAα−ca=3.35, (c) weak amino base functional group with pKBH+=8.5. The distribution of Na+ in the protein layer of a cell is found to vary with the pH of the bulk liquid phase, the possible implication of this phenomenon to cell physiology is discussed.
Colloids and Surfaces B: Biointerfaces 32(3), pp.203-212