Selective and Sensitive Electrochemical Determination of Trace Amounts of Mercury Ion in Some Real Samples Using an Ion Imprinted Polymer Nano-Modifier

A new chemically modified carbon paste electrode was constructed and used for rapid, simple, accurate, sensitive and highly selective determination of mercury (II) ion using square wave stripping voltammetry. The carbon paste electrode was modified by an ion imprinted polymer. Compared with carbon paste electrode, the stripping peak currents had a significant increase at the modified electrode. Under the optimized conditions (deposition potential, -0.600 V vs. Ag/AgCl; deposition time, 250 s; resting time, 10 s; SW frequency, 80 Hz; pulse amplitude, 70 V; dc voltage step height, 5.8 mV), the detection limit was found to be 0.04 ng mL(-1) for the determination of Hg2+ ion over a wide linear range from 0.20 to 1600.0 ng mL(-1). The effect of different cations and anions on the determination of the target ion was studied, and it was found that the electrode is highly selective for the determination of Hg2+ ion. Furthermore, the present method was successfully applied to the determination of Hg2+ in water and some foodstuff samples. (C) 2015 The Electrochemical Society. All rights reserved.