A new dodecylsulfate ion-selective sensor based on electrochemically prepared polypyrrole and PVC

Dodecylsulfate-doped polypyrrole (PPy-DS) was prepared electrochemically by anodic polymerization of pyrrole in the presence of dodecylsulfate (DS-) i ons in aqueous solution and used as a DS- sensor. The effect of polymerizat ion conditions on the characteristics of the potential response of the sens or was also investigated. The electrode made with PVC-PPy-DS membrane, plas ticized with 2-nitro-phenyloctylether (o-NPOE) showed the Nernstian behavio r (57.5 mV per decade over 10(-5) to 7 x 10(-3) M DS-) with a detection lim it of 5 x 10(-6) M. The response time of the electrode is in the order of a few seconds and can be used for at least six months without any divergence . The electrode is highly selective to DS- ion over diverse inorganic anion s.