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 Nernstian behavior (a slope of 57.2 mV per decade over 3×10−5 to 3×10−3 M DBS− ion in aqueous solution and 3×10−5 to 7×10−3 M DBS− ion in 50% methanol–water solution) with a detection limit of 2×10−5 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.