Nickel-gold bimetallic nanostructures with the improved electrochemical performance for non-enzymatic glucose determination

Abstract

Bimetallic nanostructured electrodes are promising candidates for non-enzymatic glucose detection due to their excellent selectivity and high sensitivity. In this work, a bimetallic Ni/Au non-enzymatic glucose sensor was developed by the electrodeposition of nickel nanostructures on Au nanoparticles (NP). Physical vapor deposition followed by thermal annealing was used for the growth of seeding Au (NP) on fluorine doped tin oxide (FTO) substrates. The electrochemical growth of Ni nanostructures on the Au-seeded substrates led to enhanced electrochemical responses from the modified electrodes. Cyclic voltammetry results showed considerable improvement of the electrocatalytic activity of the Ni/Au bimetallic structure in comparison to monolithic Ni and Au structures due to the synergistic effect. The sensor showed two linear ranges of 5 μM–3.5 mM and 3.5–7 mM for glucose detection with the sensitivity of 893 (μA mM−1 cm−2). The low detection limit of 0.7 μM and the fast response time of 5 s was achieved. The selectivity, reproducibility and accuracy of the fabricated sensor in determination of human serum glucose suggest its potential for large-scale production as commercial non-enzymatic glucose detection.