Facile preparation of a highly sensitive non-enzymatic glucose sensor based on the composite of Cu(OH)2 nanotubes arrays and conductive polypyrrole

Abstract

A novel amperometric non-enzymatic glucose sensor is designed by the facile preparation method. It is made by electrodeposition of Cu clusters and converting them to Cu(OH)2 nanotubes (Cu(OH)2NTs) arrays along with thin-film electro-polymerized of spindle-shaped polypyrrole (PPy@Cu(OH)2NTs), which have been doped by using sodium Benzene-1,3-disulfonate as an anion dopant. Various electrochemical methods investigate the electrochemical performance of the modified electrode toward glucose detection. Under the optimized conditions, a significant electrochemical response improvement is observed toward the electro-oxidation of glucose on the PPy@Cu(OH)2NTs electrode's surface relative to the Cu(OH)2NTs and the bare glassy carbon electrode. The designed electrode demonstrated an acceptable linear dynamic range in two wide ranges of 0.001 mM–1.78 mM and 1.78 mM–6.53 mM with high sensitivity of 910 µA mM−1 cm−2 and 675 µA mM−1 cm−2, respectively. The results are shown a low detection limit of 0.35 µM. Besides high sensitivity, this sensor represented good reproducibility and repeatability for glucose analysis and also provided relevant results for the non-enzymatic glucose determination in clinical preparations. This system also exhibits high selectivity for glucose oxidation that almost no signal was detected from interferences such as ascorbic acid, dopamine, uric acid, and chloride ions, demonstrating its great potential as a non-enzymatic glucose sensor. The superb sensing performance is ascribed to the sufficient catalytic sites of scroll-like Cu(OH)2NTs arrays morphology and synergistic effect of the doped-polypyrrole, which improve the surface area and act as a conductive binder on the electrode surface.