The ionophore X537A causes a large increase in the [(14)C]dopamine (a catecholamine) permeability of planar bilayer membranes. Dopamine transport increases linearly with the ionophore concentration. At relatively high concentrations in the presence of dopamine, the ionophore omdices a conductance which is nearly ideally selective for the dopamine cation. However, the total dopamine flux as dete...

Electrically facilitated molecular transport in an ion-exchange membrane (Nafion, 1100 equiv wt) has been studied using a scanning electrochemical microscope. The transport rates of ferrocenylmethyltrimethylammonium (a cation), acetaminophen (a neutral molecule), and ascorbate (an anion) through approximately 120-micron-thick membranes were measured as a function of the iontophoretic current pa...

A new type of cation-exchange nanocomposite membranes was prepared by in-situ formation of ZnO nanoparticles in a blend containing sulfonated poly (2,6-dimethyl-1,4-phenylene oxide) and sulfonated polyvinylchloride via a simple one-step chemical method. As-synthesized nanocomposite membranes were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray...