Cobalt(II)-selective electrode based on a newly synthesized macrocyclic compound

A cobalt(II) ion-selective membrane sensor has been fabricated in a poly(vinyl chloride) matrix based on a recently synthesized 2,3,4-pyridine-1,3,5,8,11,14-hexaazacyclohexadeca-2-ene as a neutral carrier. The electrode exhibits a Nernstian response over a wide concentration range (6.3 × 10−6 to 1.0 × 10−1 M) between pH 2.5 and 6.5. The response time of the sensor is about 15 s and it can be used over a period of 4 months without any divergence in potential. The proposed membrane sensor revealed good selectivity for Co(II) over a wide variety of other metal ions. The electrode has been used as an indicator electrode in potentiometric titration of Co(II) with EDTA and direct determination of Co(II) in wastewater of the electroplating industry.