Rapid coating of glass-capillary microelectrodes for single-electrode voltage-clamp

The single-electrode voltage-clamp technique requires sharp glass-capillary microelectrodes, whose electrical properties often limit the capabilities of the recording system. Here, we describe a rapid and simple way of coating fine microelectrodes with Dricote and Vaseline that improves their performance during voltage-clamp. The coating prevented clogging of the tips, improved the capacitance compensation of the electrodes, helped to seal the electrode tips into cell membranes and allowed visualization of the tips under saline solution. This new coating method led to greatly improved recordings and better characterization of the transduction and voltage-activated currents in an isolated preparation of spider mechanosensory neurons.