Catalytic adsorptive stripping voltammetry at a carbon paste electrode for the determination of amiodarone

Voltammetry using solid electrodes usually suffers from the contamination due to the deposition of the redox products of analytes on the electrode surface. The contamination has resulted in poor reproducibility and overelaborate operation procedures. The use of the chemical catalysis of oxidant on the reduction product of analyte not only can eliminate the contamination of analyte to solid electrodes but also can improve the faradaic response of analyte. This work introduced both the catalysis of oxidant K2S2O8 and the enhancement of surfactant Triton X-100 on the faraday response of amiodarone into an adsorptive stripping voltammetry at a carbon paste electrode for the determination of amiodarone. The method exhibits high sensitivity, good reproducibility and simple operation procedure. In 0.2 mol.L-1 HOAc-NaOAc buffer (pH = 5.3) containing 2.2 X 10(-2) mol.L-1 K2S2O8 and 0.002% Triton X-100, the 2.5th-order derivative stripping peak current of the catalytic wave at 0.3 V (vs. Ag/AgCl) is rectilinear to amiodarone concentration in the range of 2.0 X 10(-10)-2.3 X 10(-8) mol.L-1 with a detection limit of 1.5 X 10(-10) mol.L-1 after accumulation at 0 V for 30 s.