Microfabricated patch-clamp array for neural MEMS applications

Microfabricated patch clamping devices comprising planar arrays of individually addressable nozzles, fluidic channels and electrodes have been developed. Patch clamp based electrophysiological techniques are among the most widespread methods in neurophysiology and are used to address a broad range of cellular physiology and quantitative biological questions. Among the limitations of the technique are the difficulty of obtaining multiple patches on connected cells or on the same cell, limited stability of patches, and constraints on chemical and optical access to the patched membrane. The parallel array device will enable the formation of multiple seals simultaneously. The structure facilitates visualization of the interior of the patched membrane during electrical recording, as well as delivery of chemicals. The microfabrication technique gives precise control over the capacitive and resistive characteristics of the electrode channels, as well as the flow resistance, which are important factors in patch clamp recording. The device is fabricated using an SOI wafer and Deep Reactive Ion Etching to create an array of cylindrical nozzles, each of which has a core of silicon dioxide and interior walls of silicon nitride. Vertical channel segments and plumbing holes are fabricated by deep reactive ion etching through the wafer. Important electrical properties of the device were characterized, and patch clamping was attempted.