Patent ID: 8268144

Claim:
A sensor for determining a concentration of an analyte in a sample, the sensor comprising: a first substrate and a second substrate disposed over the first substrate, wherein the first and second substrates define a sensor comprising a proximal end and a distal end, the distal end being configured and arranged for insertion into a sensor reader, a first side edge and a second side edge extending from the proximal end to the distal end of the sensor, and the proximal end of the sensor comprising first and second extensions; a spacer disposed between the first and second substrates and defining a first aperture along the first side edge of the sensor, a second aperture along the second side edge of the sensor, and a sample chamber extending with a substantially uniform width from the first aperture to the second aperture; a working electrode disposed on the first substrate; an analyte-responsive enzyme disposed on the working electrode; a counter electrode disposed on the second substrate, wherein the working electrode and the counter electrode are positioned relative to the sample chamber to generate an analyte-responsive signal when sample containing analyte is disposed in the sample chamber; an indicator electrode disposed on at least one of the first and second substrates and positioned relative to a sample flow path within the sample chamber to indicate that, when sample contacts the indicator electrode, the sample chamber is filled with sample.