It follows that in practice the MM and PP mechanisms cannot be distinguished on the basis of their calibration curves alone, although the significance of the parameters extracted from their quantitative processing differs profoundly at the level of enzymatic kinetics. Similarly, PI mechanisms would be very hard to distinguish since they exhibit very similar functional dependence on experimental parameters except for the kinetic influence of the additional parameters 𝜂 and 𝜂 whose values are difficultly predictable. This extends previous conclusions drawn for fully homogeneous situations and further illustrates the added complexity for electrochemical enzyme micro-and nanosensors due to convolution of diffusional transport terms with experimental currents. Indeed, upon increasing the mechanism complexity (viz., from MM to PP and to PI) the operational parameters which govern the calibration curves quickly become complicated functions of primary parameters (see Table ). Except for MM mechanism, these operational parameters depend on more than two primary parameters. It ensues that an infinite number of primary parameter combinations can lead to a same calibration curve. This is not a problem in itself whenever the only purpose of the calibration curves is to establish a correspondence between the currents and the concentrations of substrate under identical experimental conditions.