TY - JOUR
T1 - Membrane potentials of membranes with fixed ionic sites
AU - van den Berg, A.
AU - van der Wal, P.D.
AU - Skowronska-Ptasinska, M.
AU - Sudholter, E.J.R.
AU - Bergveld, P.
AU - Reinhoudt, D.N.
PY - 1990
Y1 - 1990
N2 - A theoretical model has been developed to simulate the formation of a membrane potential as a function of physically accessible parameters. The description is an extension of the well-known Teorell-Meyer-Sievers (TMS) model, now including free and fixed ionic sites and free and fixed neutral ligands. The model shows that selectivity loss appears as the molar ratio of [ligand]/[ionic site] < 1 in the case of fixed ionic sites. The effect of complete immobilization of the neutral ligand has been simulated by gradually decreasing the mobility ratio α of the cation-ligand complex and free cation in the membrane phase. At lower α, the membrane potential is reduced by a counteracting diffusion potential. This effect is not present if the product of the association constant β1, the total ligand concentration L and α is larger than 104. Furthermore, it is shown that cation permselectivity of ion-selective membranes that contain fixed anionic sites cannot be eliminated by the incorporation of an equal amount of fixed cationic sites.
AB - A theoretical model has been developed to simulate the formation of a membrane potential as a function of physically accessible parameters. The description is an extension of the well-known Teorell-Meyer-Sievers (TMS) model, now including free and fixed ionic sites and free and fixed neutral ligands. The model shows that selectivity loss appears as the molar ratio of [ligand]/[ionic site] < 1 in the case of fixed ionic sites. The effect of complete immobilization of the neutral ligand has been simulated by gradually decreasing the mobility ratio α of the cation-ligand complex and free cation in the membrane phase. At lower α, the membrane potential is reduced by a counteracting diffusion potential. This effect is not present if the product of the association constant β1, the total ligand concentration L and α is larger than 104. Furthermore, it is shown that cation permselectivity of ion-selective membranes that contain fixed anionic sites cannot be eliminated by the incorporation of an equal amount of fixed cationic sites.
U2 - 10.1016/0022-0728(90)87058-R
DO - 10.1016/0022-0728(90)87058-R
M3 - Article
SN - 0022-0728
VL - 284
SP - 1
EP - 20
JO - Journal of electroanalytical chemistry and interfacial electrochemistry
JF - Journal of electroanalytical chemistry and interfacial electrochemistry
IS - 1
ER -