Failure mode and effect analysis of patch-clamp laboratory instrumentation for electrophysiology measurements

The patch-clamp technique is an electrophysiological method that allows the recording of the macroscopic whole-cell current as well as of the microscopic single-channel current, flowing across biological membranes through ion channels. Though different experimental preparations exist, and various types of experiments can be carried out with this technique, some basic instrumentation is common to all patch-clamp workstations: the vibration isolation table, the Faraday cage, the microscope, the micromanipulator, the amplifier, the pc, the pipette puller, and the microforge. Failures in the electronic instrumentation can markedly affect current recordings, as their amplitudes usually range between a few pA and a few nA, thus influencing the accurate assessment of the effect of drugs on ion channels. In this paper different types of failure that may occur in the electronic instrumentation for the patch-clamp are discussed. Moreover, an analysis of their effect on the acquired measurements during electrophysiology experiments is carried out.