A unitary ionic probe is provided. The unitary ionic probe includes a substantially elongate body including a central axis (AA), a proximal end, and a distal end. The unitary ionic probe further includes an active ion sensitive region that is located on and bonded into an exterior of the elongate body in a region of the proximal end and an active electrode in ionic communication with the active ion sensitive region. The unitary ionic probe further includes a reference ion sensitive region that is located on and bonded into the exterior of the elongate body and is spaced-apart from the active ion sensitive region and a reference electrode in ionic communication with the reference ion sensitive region.