Embodiments provide sensors, such as implantable sensors, and methods of producing such sensors. An implantable sensor may include a base, one or more chambers, and one or more sensor reagents. A membrane may be coupled to the chambers over the sensor reagents. The implantable sensor may be at least partially implanted into the dermis of an animal. One or more of the sensor reagents may emit light or exhibit a color change in response to the presence of a target analyte or reaction product thereof. The response may be detected and analyzed by the user or by a reader device to determine the target analyte concentration.
