A highly selective and sensitive plasticized membrane sensor for Ag+ ions based on 2-methyl-2,4-di(2-thienyl)-2,3-dihydro-1H-1,5-benzodiazepine (MTHB) as membrane carrier was prepared. The sensor shows a linear dynamic range of 1.0 × 10-6 -1.0 × 10-1 mol L-1, with a Nernstian slope of (58.5±0.3) mV decade-1, and a detection limit of 5.0 × 10-7 mol L-1 (~54 ppb). It has a fast response time of 10 s and can be used for at least eight weeks without any considerable divergences in its potentials. The proposed sensor revealed very good selectivities with respect to the most of common metal ions. The proposed sensor could be used in a pH range of 4.0-8.0. It was successfully used as an indicator electrode in potentiometric titration of Ag+ with NaCl.
potentiometric sensor; Ag+ sensor; PVC membrane; 2-methyl-2,4-di(2-thienyl)-2,3-dihydro-1H-1,5-benzodiazepine (MTHB)
