Diffusion-controlled Mediated Electron Transfer-type Bioelectrocatalysis Using Microband Electrodes as Ultimate Amperometric Glucose Sensors.

We performed numerical simulations on an extremely fast, mediated, electron transfer-type bioelectrocatalytic reaction using a microband electrode. The simulations under fast-enzyme-kinetics conditions predicted that the decrement of the current density by increaseing the microband thickness would effectively improve the upper limit of detection. These predictions were accurate for an ultrathin-ring with thickness of 100 nm and gold leaf with thickness of 10 μm electrodes, acting as novel amperometric glucose sensors with FAD-dependent glucose dehydrogenase. The gold leaf electrode provided pseudo-steady-state currents which were proportional to the glucose concentration up to a concentration of 20 times higher than the mediator concentration.