Application of irreversible thermodynamics to a functional description of the tumor cell membrane

The permeability of the membranes of several strains of Ehrlich mouse ascites tumor cells to a series of homologous glycols was analyzed with equations from irreversible thermodynamics. Experimental data were fitted to the appropriate equations of Kedem and Katchalsky by means of an analog computer and values for σ, L_p, and ωRT were calculated. These parameters would become part of a functional profile of the membrane of the tumor cell. The glycols cross the membrane with energies of activation ranging from 16 kcal/mole for ethylene glycol to 20 kcal/mole for triethylene glycol. Entropies of activation ranged from 17 to 27 entropy units. This analysis provided several additional dividends. It is one of the few examples with a mammalian cell where the kinetics of non-electrolyte transport have been described completely by the equations of irreversible thermodynamics. It has provided the means to distinguish how much of the transport occurred through porous paths in the membrane and how much involved solution within the matrix of the membrane. Finally, several tumor cell populations have been distinguished through these functional properties of their membranes.