Fast Fourier continuous cyclic voltammetry at gold ultramicroelectrode in flowing solution for determination of ultra trace amounts of penicillin G

摘要

In this work, for the first time a fast continuous cyclic voltammetry was used as a highly sensitive detection method for Penicillin G in a flow-injection system. A special computer-based numerical calculation method (using Fast Fourier Transformation) is introduced here for enhancing the analyte signal and noise reduction. During the measurements, the potential waveform (consists of potential steps for cleaning, stripping and potential ramp) was continuously applied on an An disk microelectrode (with a radius 12.5 mu m in radius). The stripping time was less than 200 ms. Effects of rest potential, sweep rate, and delay time on the sensitivity of the method were investigated. The limit of detection of the method was 1.0 x 10(-11) M. The detection limit of the method is 660 times lower than the most sensitive reported method. The relative standard deviation of the method at 1.0 x 10(-7) M of Penicillin G was 2.7% for 10 runs.