Pseudo painting/air bubble technique for planar lipid bilayers

Background: A functional reconstitution of channel proteins in planar lipid bilayers is still very versatile to study structure/function correlates under well-defined conditions at the single protein level. New method: In this study we present an improved planar lipid bilayer technique in which an air bubble is used for stabilizing unstable/leaky bilayers or for removing excess lipids. The bubble can also be used as a tool for reducing the number of channels in the bilayer with the goal of having only one active channel in the membrane. Results: Stable planar lipid bilayers are formed within seconds to minutes. In the case of multiple channel insertion the air bubble can be used to reduce the number of channels within minutes. Comparison with existing method(s): The simple improvement of the classical folding technique guarantees a very fast creation of stable bilayers even with difficult phospholipids in a conventional vertical bilayer set-up; it requires no modifications of the existing set-up. Conclusions: This technique is very easy to handle and guarantees successful single channel recordings for any kind of planar lipid bilayer experiment.