Sub-Second Accumulation and Stripping for Pico-Level Monitoring of Amikacin Sulphate by Fast Fourier Transform Cyclic Voltammetry at a Gold Microelectrode in Flow-Injection Systems

Abstract

This study presents an easy and fast stripping voltammetric detection technique for the determination of amikacin sulfate in a flow-injection system. For a very sensitive determination, the currents were integrated for a whole potential scan range including oxidation and reduction of the gold surface electrode. The potential waveform, which consisted of potential steps for cleaning, stripping and potential ramp, was continuously applied to a gold disk ultra-microelectrode (with a diameter of 50 μm). The greatest advantages of the proposed detection method are a) very low detection limit (picomolar level), b) removing oxygen from the test solution is not necessary, c) very fast and appropriate for monitoring drug compounds in a wide variety of chromatographic analysis methods. The detection limit for amikacin sulfate was 2.0 × 10−11 M (∼15 pg mL−1), and the relative standard deviation for 10 determinations of 1.0 ng mL−1 of amikacin was 3.2%. The effects of scan rate, accumulation potential, accumulation time and pH of eluent on the performance of the method were investigated. The results were used for the determination of amikacin sulfate in pharmaceutical preparations.