The mechanism of pulsed potential waveform for monitoring antibody–antigen interactions at immunosensor interfaces is discussed. Some examples of antibody–antigen interactions at quartz crystal microbalance and polymer-modified antibody electrodes are presented. The binding and release of analytes to the modified sensor surfaces are monitored in real time. An overview of the analytical performance of some recently developed sensors utilizing pulsed amperometric detection techniques is also presented. The sensors obtained are reversible and reproducible (with a relative standard deviation of 0.30%), and their response times are in the millisecond range.