Linear alkylbenzenesulfonate (LAS) ion-selective electrode based on electrochemically prepared polypyrrole and PVC

Dodecylbenzenesulfonate-doped polypyrrole (PPy-DBS) was prepared electrochemically by anodic polymerization of pyrrole in the presence of dodecylbezenesulfonate (DBS-) ions in aqueous solution and used as the ionophore For construction of sensor. The electrode made of PVC-PPy-DBS membrane and plasticized with ortho-nitrophenyloctylether (o-NPOE) and hyamine as additive showed the Nemstian behavior (a slope of 57.2 mV per decade over 3 x 10(-5) to 3 x 10(-3) M DBS- ion in aqueous solution and 3 x 10(-5) to 7 x 10(-3) M DBS- ion in 50% methanol-water solution) with a detection limit of 2 x 10(-5) M. The response time of electrode is about 20 s and can be used for at least 6 months without any divergence. The electrode is highly selective to DBS ion over diverse inorganic anions. (C) 2001 Elsevier Science B.V. All rights reserved.