Patent ID: 8535499

Claim:
A micromachined free-diffusion liquid-junction reference electrode comprising: an internal electrode reservoir configured to contain an electrolyte; an internal electrode in the internal electrode reservoir configured to contact with the electrolyte when present; a pinhole configured to provide a fluidic contact to a sample solution; and at least one high-aspect-ratio channel connecting the internal electrode reservoir and the pinhole, wherein the electrolyte is configured to freely diffuse from the internal electrode reservoir to the pinhole through the high-aspect-ratio channel, wherein the at least one high-aspect-ratio channel has one or more of an inlet part connected to the internal electrode reservoir, an outlet part connected to the pinhole, and a folded geometry in between the inlet part and the outlet part, wherein the reference electrode further comprises at least one electrically conductive strip configured to form a low impedance bypass for the high-aspect-ratio channel, wherein the electrically conductive strip is configured to connect the inlet part of the high-aspect-ratio channel closest to the electrolyte reservoir comprising the internal electrode and the outlet part of the high-aspect ratio channel.