Nickel(II) ion-selective electrode based on 2-methyl-4-(4-methoxy phenyl)-2,6-diphenyl-2H-thiopyran

A new PVC membrane electrode for nickel ion based on a recently synthesized 2-methyl-4-(4-methoxy phenyl)-2,6-diphenyl-2H-thiopyran as membrane carrie r was prepared. The sensor exhibits a Nernstian response for Ni2+ over a wi de concentration range (5 x 10(-2) 2 x 10(-5) M) with a limit of detection of 9 x 10(-6) M. The response time of the sensor is ca. 10 s and the membra ne can be used for more than 8 weeks without observing any deviation. The p roposed membrane sensor shows excellent discriminating ability towards Ni2 ion in comparison to several alkali, alkaline earth, transition and heavy metal ions. It was used as an indicator electrode in potentiometric titrati on of Ni ions in bath water and 85% acetonitrile solutions.