Cadmium(II) ion selective electrode based on pyridine-3-carboxyaldehyde thiosemicarbazone

Department of Chemistry, S.S.V. (P.G.) College, Hapur, India

Department of Chemistry, Zakir Hussain College (University of Delhi). J. L. Nehru Marg,

New Delhi-110 002, India

E-mail : himan_007@rediffmail.com

Manuscript received 13 August 2004, revised 1 November 2004, accepted 2 February 2005

A new polyvinyl chloride (PVC) membrane electrode based on pyridine-3-carboxyaldehyde thioscmicarbazonc was pt·eparcd using 2-nitrophenyl-octyl ether as plasticizer for Cd^II selective sensor. The sensor exhibits a Nernstian response for Cd^II ion over a wide concentration range (5 x 10^-2-2 x 10^-5 M). The electrode assembly works between pH 2.5-7.0, exhibits a response time of <20 sand performed satisfactorily over a period of 3-4 months with good reproducibility. The electrode exhibits excellent selectivity of the order of 10^-3 over a number of bivalent cations and also demonstrates its utility as an indicator electrode in the potentiometric titration of Cd²⁺ with EUTA.