A rapid cadmium determination based on ion selective membrane potentiometric sensor by bis (salicylaldehydo) ethylenediimine as carrier

An ion selective potentiometric electrode (IPE) was prepared based on salen material (bis(salicylaldehydo)ethylenediimine) as a suitable carrier for determination of cadmium ions. An acceptable response for cadmium ions obtained over a linear range ۸ × ۱۰−۷ to ۱.۰ × ۱۰−۲ M with a slope of ۲۹.۸ ± ۰.۸ mv per decade of activity and a detection limit of ۳.۲ × ۱۰−۷ M for Cd (II) ions in water and liquid samples. It has a response time less than ۱۰ s and can be used for at least ۲.۵ months without any measurable divergence in potential. The ion selective electrode can be used based on potential and potential changes in the pH range ۳.۵ to ۶.۵, so, the cadmium determination was obtained at independent pH. Moreover, the selectivity of proposed method in presence of interference ions was studied. The results showed that the other cations do not interfere significantly in response electrode at optimized pH. This electrode was successfully used for the determination of cadmium ions in aqueous samples. The validation was obtained based on ICP analyzer and certified reference material in water samples (CRM, NIST).

کلیدواژه ها:

Cadmium ، Ion selective electrode ، Membrane sensor ، Potentiometry ، Salen ، Water samples