Development of a novel cyano group containing electrochemically deposited polymer film for ultrasensitive simultaneous detection of trace level cadmium and lead

Poly(diphenylamine-co-2-aminobenzonitrile) (P(DPA-co-2ABN)), a cyano group containing conducting polyaniline derivative, has been electrodeposited developed as the new material and utilized for the simultaneous electrochemical determination of trace levels of cadmium (Cd2+) and lead (Pb2+). P(DPA-co-2ABN) film preconcentrates effectively through cyano chelation and electrochemically strips the heavy metal ions with well separated potentials, which are beneficially utilized for ppb level simultaneous detection of Cd2+ and Pb2+. Differential pulse voltammetry studies revealed that Cd2+ and Pb2+ ions were simultaneously stripped with well-defined, separated and sharp peaks for Cd2+ and Pb2+. The influence of various operational parameters such as pulse amplitude, pulse time, scan rate, initial potential, end potential, accumulation potential and accumulation time on the electrochemical stripping of heavy metals were investigated in details. Under the optimal conditions, good linear correlations were obtained from 1.26 to 907.8 ppm for Cd2+ and 0.26 to 58.73 ppm for Pb2+, respectively. Low detection limits for Cd2+ and Pb2+, 0.255 ppm and 0.165 ppm, respectively, were observed. The practical utility of the new procedure was demonstrated in real samples. (c) 2012 Elsevier B.V. All rights reserved.