Digital Alternating Current Polarography with Microprocessor-Based Instrumentation

Abstract

The technique of digital ac polarography is described. In this technique, a small amplitude digital sine wave is applied to the cell instead of an analog sine wave. This signal is obtained from a microprocessor-based function generator and data acquisition system. Assuming that the 36-step sine wave produces a response similar to that in conventional ac polarography, current data are collected every 10° relative to the applied signal. By simulating the various electronic components found in conventional ac instruments, phase-sensitive detection of fundamental and second harmonics is also possible. A qualitative comparison between the absolute current polarograms and of the phase-sensitive fundamental harmonics is in excellent agreement with ac polarographic theory for a reversible system. © 1981, American Chemical Society. All rights reserved.