CuO nanowires based sensitive and selective non-enzymatic glucose detection

Copper oxide nanowires (CuO NWs) were prepared by a facile two-step procedure consisting of wet-chemistry synthesis and subsequent direct calcination. The morphology, surface property, and crystal structure of the as-prepared CuO NWs were characterized by SEM, TEM, and XRD. The CuO NWs were further employed to construct a non-enzymatic glucose sensor with excellent performance toward glucose detection in 50 mM NaOH solution. The as-developed non-enzymatic glucose sensor showed a fast response time (less than 5 s) and a wide dynamic range with excellent sensitivity of 648.2 μA cm−2 mM−1 and 119.9 μA cm−2 mM−1 toward glucose detection at an applied potential of +0.55 V and +0.3 V (vs. Ag/AgCl), respectively. The Langmuir isothermal theory was employed to fit the obtained calibration curves with high correlation coefficient and the mechanisms for the glucose oxidation promoted by CuO NWs were also discussed. The good selectivity of the CuO NWs based non-enzymatic glucose sensor against electroactive compounds such as ascorbic acid, uric acid, and acetaminophen, and other sugars such as fructose and sucrose at their physiological concentrations were also demonstrated. Furthermore, good accuracy and high precision for the quantification of glucose concentration in human serum samples was attested. These good features indicate that CuO NWs have a great potential in the development of sensitive and selective non-enzymatic glucose sensor.