A Glucose Sensor Based on a Nano-Structured Metal Composite Oxide Derived from Hydrotalcite

A nano-structured composite oxide (Mg(Ni)FeO) has been prepared through calcining its precursor hydrotalcite by coprecipitation. A simple and cheap glucose biosensor based on Mg(Ni)FeO matrix immobilizing glucose oxidase at glassy carbon electrode was fabricated, and characterized by scanning electron microscopy, transmission electron microscopy, UV-vis spectroscopy, and electrochemical impedance spectroscopy. The experimental parameters such as pH values, applied potentials and amount of the modifier matrix have been explored for the optimum analytical performances of the biosensor. Under the optimum conditions, the biosensor exhibited good electrochemical performances to glucose with a rapid response (<5 s), a linear range of 1.0-10.0 mM, a detection limit of 0.1 mM based on S/N = 3 and a sensitivity of 2.66 mu A mM(-1). The modified electrode was applied to detect glucose concentration in real samples. The biosensor displayed satisfactory results with good repeatability and accuracy.