Nonenzymatic glucose sensor based on gold–copper alloy nanoparticles on defect sites of carbon nanotubes by spontaneous reduction

Gold (Au) and copper (Cu) alloy catalysts were deposited on the defect sites of carbon nanotubes by spontaneous reduction among AuCl₄^?, Cu²⁺ and oxygen-containing functional groups. Compared with AuCu alloy catalysts prepared by adsorption methods and electrochemical deposition methods, AuCu alloy catalysts show excellent catalytic ability to glucose by spontaneous reduction. The linear range of nonenzymatic sensors that were prepared by spontaneous reduction for glucose detection is 0.08–9.26 mM, and detection limit is 4 μM. In addition, there are high sensitivity (22 μA mM^?1), reproducibility (96%) and stability (95% after 60 days). Selectivity of this nonenzymatic sensor for ascorbic, uric acid and acetaminophen was also obtained.