New neutral carrier-based H+ selective membrane electrodes


H+-selective membrane electrodes based on two neutral ion carriers of the class of phenoxazine derivatives which contain different lipophilic imino chains (9-(diethylamino)-5-octadecanoylimino-5H- benzo[a]phenoxazine and 9-(dimethylamino)-5-[4-(16-butyl-2,14-dioxo-3,15-dioxaeicosyl)phenylimino]- 5H-benzo[a]phenoxazine respectively) are described. Both ionophores, previously used as chromo-ionophores in optode construction, with added potassium tetrakis(p-chlorophenyl) borate (KTpClPB) as cation exchanger sites were embedded into a high molecular weight poly(vinyl chloride) matrix containing o-nitrophenyl octyl ether (o-NPOE) as plasticizer. Both polymeric pH electrodes exhibited near -Nernstian responses over the ranges depending on the pK of the ionophore within the membrane used as electroactive material. The selectivities and other main characteristics of the electrodes are presented. © 1992.

Publication Title

Journal of Electroanalytical Chemistry