MICRO & NANO LETTERS, vol.13, no.10, pp.1431-1436, 2018 (SCI-Expanded)
In this work, a new nanocomposite as silver nanoparticles (AgNPs)@ porous silicon (PSi) was synthesised through a simple galvanic displacement reaction between silver ions and silicon in the presence of hydrofluoric acid. The as-prepared nanocomposites were characterised via field emission scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy and electrochemical methods. Since the nanocomposite showed a greatly enhanced electrocatalytic activity towards the glucose oxidation in alkaline solution, Ag nanoparticles supported on PSi flour were used as a performance modifier in the construction of a new amperometric glucose screen-printed carbon electrode. The enzymatic free glucose sensor based on AgNPs@PSi exhibited a wide linear dynamic range of 1 x 10(-6)-45.7 x 10(-3) M, with a detection limit of 6 x 10(-7) M at a signal-to-noise ratio of 3, and fast response (<3 s). Also, the response of the proposed sensor was selective towards glucose in the presence of common species such as ascorbic acid, dopamine, uric acid and Cl- ions. Finally, the sensor was successfully applied to determine glucose in human serum samples.