where A is the sensitivity parameter of the chemical sensor-actuator system and is
determined by the are of the generating electrode (and thus the current density) and
the diffusion speeds in the membrane.
The generating current is used to compensate the pH changes produced by the enzyme
and hence ∂Vout,current= -∂Vout,enzyme. Combination of Eqns. 38 and 39 shows that the
sensitivity of the pH-static enzyme sensor is given by