Highly selective PVC-membrane electrodes based on Co(II)-Salen for determination of nitrite ion.
A cobalt(II) derivative was used as a suitable ionophore for the preparation of a polymeric membrane nitrite-selective electrode. The electrode reveals a Nemstian behavior over a very wide NO2- ion concentration range (1.0 x 10(-6)-1.0 x 10(-1) M) and a very low detection limit (5.0 x 10(-7) M). The potentiometric response is independent of the pH of solution in the pH range 4.0-9.5. The electrode shows advantages such as low resistance, fast response and, most importantly, good selectivity relative to a wide variety of inorganic and organic anions. In fact, the selectivity behavior of the proposed NO2- ion-selective electrode shows great improvements compared to the previously reported electrodes for nitrite ion. The proposed electrodes could be used for at least 2 months without any significant changes in potentials. The electrode was successfully applied to the determination of nitrate ion concentrations in sausage and milk samples.
Ganjali
Mohammad Reza
MR
Department of Chemistry, Tehran University, Tehran, Iran. Ganjali@khayam.ut.ac.ir
Rezapour
Morteza
M
Pourjavid
Mohammad Reza
MR
Salavati-Niasari
Masoud
M