The properties of ionic channels measured by noise analysis in thin lipid membranes

Noise analysis was performed on the membrane currents produced by the ion channel former gramicidin A in black lipid bilayer membranes. The average channel lifetime and the unit channel conductance can be determined from the autocorrelation function. The values agree with the independently obtained data from measurements of single channels. The dependence of this function on the channel density reveals information on the process of channel formation. The kinetic information is the same as that obtained by voltage clamp measurements