Carbon nanotube transistor controlled by a biological ion pump gate.

We report a hybrid bionanoelectronic transistor that has a local ATP-powered protein gate. ATP-dependent activity of a membrane ion pump, Na(+)/K(+)-ATPase, embedded in a lipid membrane covering the carbon nanotube, modulates the transistor output current by up to 40%. The ion pump gates the device by shifting the pH of the water layer between the lipid bilayer and nanotube surface.