“…Calculating the electroactive surface area permitted the study of the electrocatalytic activity of the sensors, which was performed by applying the Randles–Sevick equation [ 20 , 21 ] to quasi-reversible redox processes controlled by diffusion. As demonstrated below, the peak current intensity on both the anodic and cathodic peaks is directly proportional to the square root of the scan rate: where Ip is the peak current (µA), n is the number of transferred electrons ( n = 1, in this example), A is the electrode active surface area (cm 2 ), C 0 is the concentration of K 3 [Fe(CN) 6 ] (mol cm −3 ), D R is the diffusion coefficient (7.60 × 10 −6 cm 2 s −1 ), and υ is the scan rate (V s −1 ).…”