Physico-chemical aspects of some biological membranes. I. Membrane potentials of the inner membrane of chicken egg in presence of alkali chlorides without and with control of pores

Abstract

The inner thin membrane obtained after removing the outer hard cover of a chicken egg has been found to record membrane potentials when it separates two different concentrations of an alkali chloride. The small negative potentials follow the sequence K +>Na +>Li + and more or less correspond with the membrane diffusion potentials. When this membrane is impregnated with potassium zinc ferrocyanide precipitate, the membrane potentials are high positive values showing enhanced preference for K + ions and also follow the order K +⪢Na +>Li +. The values, however, are less than the theoretical Nernstian values. Apparent fixed charges developed in this precipitated membrane are calculated using some classical equations. The comparison shows that the results with different equations are quite agreeable. In the TMS method the charge densities follow the order K +>Na +>Li +, but for the other methods it is K +>Na +∼Li +.