The magnitude of the photoinduced membrane potential across poly(vinyl chloride)/spirobenzopyran membranes doped with nonactin or valinomycin depended considerably upon the kind and the concentration of alkali-metal and NH4 cations in the aqueous solution adjacent to the ultraviolet (UV)-irradiated surface of the membrane. The photoresponse was suppressed with increasing concentration of the cations. The ion-selectivity in the potentiometric photoresponse of the nonactin-entrapped membrane was in the order of NH4 >K+ >Rb+ >Cs+ >Na+ >Li+, whereas the order of selectivity of Rb+ >K + >Cs+ >NH4 >Na+ >Li+ was observed for the valinomycin-doped membrane. The results can be explained in terms of the binding abilities of nonactin and valinomycin for alkali-metal and NH/ cations.
- photoinduced membrane potential
- poly(vinyl chloride)/spirobenzopyran membrane
ASJC Scopus subject areas
- Drug Discovery