Au Nanospikes as a Non-enzymatic Glucose Sensor: Exploring Morphological Changes with the Elaborated Chronoamperometric Method

There is a continuous increasing demand for more sensitive and selective non-enzymatic glucose sensor applications ranging from medical diagnostics to food quality assurance. Here, we deposited gold nanostructures (referred to as Au nanospikes) on Au thin-film substrates under different electrodeposition conditions in order to determine the optimal growth parameters to obtain an enhanced glucose sensor. A modified chronoamperometric technique was employed to determine the glucose electrooxidation and sensing capabilities of the developed Au nanospikes toward 20 mu M-10 mM glucose concentrations. The sensing method used here allowed for accurate determination of glucose concentrations whilst providing reproducible and stable response profiles. The sensor produced a low detection limit of 20 mu M, a very high sensitivity of 201 mu A mM(-1).cm(-2) compared to 16.19 mu A mM(-1).cm(-2) for the unmodified Au substrate. The sensor also showed good selectivity when analysed against common physiological contaminants that usually interfere with conventional sensors.