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A series of non‐enzymatic electrochemical glucose sensors were prepared by template‐assisted electrodeposition of nickel to produce nickel nanowire arrays (NiNWAs) of varying lengths. These electrodes were analyzed for their performance as non‐enzymatic glucose sensors, in order to explore the relationship between nanowire structure and electrochemical sensor performance. All of the NiNWAs, regardless of length, had linear responses to glucose in the 0.05–10 mM range. However, an inverse relationship between wire length and sensitivity was observed: the shortest of the NiNWAs had a sensitivity of 160 μA mM−1 cm−2, while the longest NiNWA had a sensitivity of only 100 μA mM−1 cm−2. This indicates that, with no other change to material parameters, choosing an optimum length of nanowire provides significant improvement in performance. No change in electrochemical mechanism was observed by cyclic voltammetry, and no significant loss of selectivity was observed with varying nanowire length. This study demonstrates that the structural optimization of an electrode can provide significant performance enhancement for nickel‐based electrochemical sensors. [ABSTRACT FROM AUTHOR]

The detection of glucose at low concentrations using electrochemical sensors is of great importance due to the possibility of using different human body fluids than blood, such as e. g. urine, saliva, sweat or tears. The interest behind those biofluids is related to their utility in non‐invasive sugar determination. In this work, we present flexible, fully biocompatible electrode material based on Au nanoparticles immobilized onto titanium dimples. Au−Ti heterostructures were obtained via electrochemical anodization of titanium foil in presence of fluoride anions followed by chemical etching, magnetron sputtering of gold and subsequent thermal dewetting in continuous regime. In the last step of fabrication, electrodes were modified by permselective Nafion membrane. The selection of the best electrode material among different configurations was carried out basing on the electrochemical activity in the contact with 5 mM glucose dissolved in neutral air‐saturated 0.1 M PBS. For the 10 nm Au dewetted gold film, limit of detection of 30 μM and high sensitivity of 93 mA cm−2 mM−1 were achieved. Application of Nafion membrane caused complete inhibition of the impact of various interference species onto the glucose detection. Good selectivity and repeatability combined with the resistance to prolonged mechanical stress suggest that prepared material can be used in non‐invasive glucose sensing. [ABSTRACT FROM AUTHOR]

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 µM-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 µM, a very high sensitivity of 201 µA mM−1 ⋅ cm−2 compared to 16.19 µA 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. [ABSTRACT FROM AUTHOR]