Quantised transistor response to ion channels revealed by nonstationary noise analysis

We report on the quantised response of a field-effect transistor to molecular ion channels in a biomembrane. HEK293-type cells overexpressing the Shaker B potassium channel were cultured on a silicon chip. An enhanced noise of the transistor is observed when the ion channels are activated. The analysis of the fluctuations in terms of binomial statistics identifies voltage quanta of about 1 mu V on the gate. They are attributed to the channel currents that affect the gate voltage according to the Green's function of the cell-chip junction. Copyright (C) EPLA, 2011