Improvement Of Transient Artifact Cancellation In Automatic Patch-Clamp Amplifier

The Patch-Clamp Technique is a milestone in the field of electrophysiology. It has been widely used in the research of life science since it was invented. By the need of electrophysiological research and the development of electronic technology, the patch-clamp technique improves quickly.The patch-clamp amplifier is essentially a sensitive current-to-voltage converter, converting small pipette currents into voltage signals that can be sampled easily. To recording the electrophysiological signals accurately, the resistance-feedback patch-clamp amplifier must cancel the transient currents caused by fast-capacitance, slow-capacitance and series-resistance in some recording mode.Compared to the conventional patch-clamp amplifier, the computer-controlled style, as a virtual instrument, allows a number of operations to be automated such as capacitive-transient cancellation and series-resistance compensation. This thesis describes the principle of the capacitive-transient and the series-resistance in the patch-clamp amplifier, designs the transient cancellation circuitry and algorithms according to the electrical model, and realizes the automatic adjustment of the circuitry through the computer. The experimental result of the design demonstrates that the compensation technology could speed up the transient cancellation effectively and improve the efficiency. Furthermore, the precision of experiments can be improved by the automatic calibration and the faults of the hardware can be diagnosed by the automatic test.