Pt nanoparticles-functionalized hierarchically porous γ-Al2O3 hollow spheres based electrochemical sensor for ultrasensitive guaiacol detection

This work reports the synthesis of novel hierarchically organized gamma-Al2O3 hollow sphere via a facile chemically induced self-transformation method, which was then used as supports for Pt catalyst. The functional Pt-gamma-Al2O3 composite showed an excellent accumulation ability and high electrochemical activity due to the nanoflower-like porous surface textures. Using guaiacol as an analyte the Pt-gamma-Al2O3 modified electrode showed a sensitive oxidation response. This speciality led to a novel methodology for the design of guaiacol sensor. Under optimal conditions, the proposed sensor showed wide linear range from 0.05 to 30 mu M and a detection limit down to 17.9 nM. Compared to the present assay methods, this method is more simple, rapid, sensitive and flexible. Therefore, the newly designed amplification strategy holds great potential for ultrasensitive electrochemical sensing of other polyphenol. (C) 2015 Elsevier B.V. All rights reserved.