Ion channels and lipid bilayer membranes under high potentials using microfabricated apertures

Membrane-bound proteins are important from both a scientific and a technological point of view. However, their study and application require a stable lipid bilayer to maintain protein function. Here we provide a method for producing lipid bilayers across apertures on a silicon substrate using a Langmuir-Blodgett technique commonly used with Teflon films. These bilayers display the same properties as those across apertures in Teflon in terms of capacitance, conductance, noise, and protein insertion and function. In addition, the bilayers remain stable at higher transmembrane potentials than those in Teflon, typically remaining unbroken over +/- 400 mV. These properties are demonstrated by the insertion of the staphylococcal protein pore a-hemolysin into pre-formed bilayers, and subsequent current recording at high potentials (+/- 400 mV).