Abstract
A new poly(4-vinyl pyridine) (P4VP) based cadmium (Cd)-ion selective electrode (ISE) was developed. The 4-vinyl pyridine (4VP) was first polymerized electrochemically on the surface of graphite, later characterized by FTIR, SEM/EDX and then optimized as ISE for Cd. At optimal pH 6.4, slope of 27.7 +/- 0.8 mV decade(-1), linear concentration range of 1 x 10(-7) to 1.0 x 10(-1) M Cd2+ and limit of detection (S/N = 3) of 2.51 x 10(-8) M were obtained. The ISE was very selective towards Cd2+, with K-pot < 1 x 10(-2) in the presence of the usual cations and anions in water samples. Response time and shelf life of less than 1 min and 90 days, respectively, were observed. Its application was tested in various types of samples. (C) 2011 Elsevier B.V. All rights reserved.