Polymeric Membrane Silver-ion Selective Electrodes Based on Schiff Base N,N'-Bis(pyridin-2-ylmethylene)benzene-1,2-diamine

Abstract

The Schiff base N,N'-bis(pyridin-2-ylmethylene)benzene-1,2-diamine [BPBD] has been synthesized and explored as ionophore for preparing PVC-based membrane sensors selective to the silver (<TEX>$Ag^+$</TEX>) ion. Potentiometric investigations indicate high affinity of this receptor for silver ion. The best performance was shown by the membrane of composition (w/w) of ionophore: 1 mg, PVC: 33 mg, o-NPOE: 66 mg and additive were added 50 mol % relative to the ionophore in 1 mL THF. The sensor works well over a wide concentration range <TEX>$1{\times}10^{-3}$</TEX> to <TEX>$1.0{\times}10^{-7}$</TEX> M by pH 6 at room temperature (slope 58.6 mV/dec.) with a response time of 10 seconds and showed good selectivity to silver ion over a number of cations. It could be used successfully for the determination of silver ion content in environmental and waste water samples.