The present invention disposes a membrane between two electrical conductive walls having a height at least as great as the thickness of the membrane. The conductive walls are fabricated on an electrically insolative chip base. The chip base has one or more through hole between the electrically conducting walls. The chip is placed inside a container having a well below the through hole of the electrically insolative base. At least one passageway extends from the well to the periphery of the container. This invention probes changes of the membrane as an in-plane electric field is applied between the conductive walls. The well may include various compounds while-other compounds can be placed in contact with the top of the membrane. The passageways are used to introduce substances into and out of the well.