Laser-Induced Mesoporous Nickel Oxide as a Highly\nSensitive Nonenzymatic Glucose Sensor

Abstract

In\nthis paper, we present a novel laser-induced oxidation procedure\nfor in situ formation of nickel oxide nanoporous structures directly\nonto the nickel surface as a highly sensitive nonenzymatic glucose\nsensor. The formation of mesoporous nickel oxide is confirmed by field-emission\nscanning electron microscopy, energy-dispersive X-ray spectroscopy,\nand X-ray diffraction. Electrochemical properties of the pristine\nand laser-induced oxidized nickel (LIO-Ni) films were studied using\ncyclic voltammetry and electrochemical impedance spectroscopy. The\nunique three-dimensional mesoporous architecture of the oxide film\non the LIO-Ni electrode resulted in a dramatic enhancement in electrochemical\nreduction/oxidation performance with a 10-fold increase in electrocatalytic\nactivity for nonenzymatic glucose oxidation as compared to the pristine-Ni\nelectrode. The LIO-Ni biosensor performance was successfully examined\nfor the amperometric detection of glucose over a wide concentration\nrange from 5 μM to 1.1 mM with a high linear sensitivity of\n5222 μA mM^–1 cm^–2. The limit\nof detection was obtained as low as 3.31 μM with a signal-to-noise\nratio of 3. Furthermore, the LIO-Ni electrode showed outstanding long-term\nstability, reproducibility, and high selectivity in the presence of\nvarious interfering agents including uric acid, l-ascorbic\nacid, acetaminophen, glutamic acid, and citric acid. The demonstrated\nlaser-induced oxidation process can be potentially adapted to the\nscalable manufacturing of a wide range of other easy-to-use and robust\nmetal oxide-based sensors for nonenzymatic biosensing applications.