M. Minagawa et al., AMINO-ACID-TRANSPORT THROUGH CATION-EXCHANGE MEMBRANES - EFFECTS OF PH ON INTERFACIAL TRANSPORT, Journal of colloid and interface science, 188(1), 1997, pp. 176-182
We present a series of experiments especially designed to show the eff
ects of pH on the interfacial transport of glycine through a cation ex
change membrane. The experimental results are explained qualitatively
by using a theoretical model which incorporates the equilibrium dissoc
iation equations for the fraction of amino acid forms at different pH
values, a rate equation for the membrane interfacial transport based o
n the interfacial chemical reaction, and the Nernst-Planck flux equati
ons for the ion transport through the bulk of the membrane. The result
s appear to indicate that the rate-limiting step in the amino acid tra
nsport process could be the rate at which glycine exits the membrane,
and they contribute to a better understanding of amino acid permeation
across charged membranes. (C) 1997 Academic Press.