Au decorated core-shell structured Au@Pt for the glucose oxidation reaction

Abstract

Core-shell structured Au@Pt nanoparticles (NPs) with Au cores and dendritic Pt shells have been synthesized using the sonochemical method. Then, the Au is electrochemically incorporated into nano-channels between the Pt shells on the Au@Pt NPs (Au@Pt/Au NPs) to form a non-enzymatic glucose sensor. The electrochemically active surface area (ECSA) of the obtained Au@Pt/Au NPs is enlarged compared with that of Au@Pt NPs, which leads to enhanced glucose sensing performance. The particle sizes of Au@Pt/Au NPs are in the range from 35 nm to 60 nm. The ECSA of Au@Pt/Au NPs is calculated to be 6.19 m2 g(Pt)−1 and 0.8 m2 g(Au)−1 by cyclic voltammetry. The Au incorporation into the Pt shell region can boost the glucose oxidation process even at neutral pH. The sensor performance under the optimized experimental conditions has been confirmed in phosphate buffered saline (PBSsal) solution, showing two wide dynamic ranges for glucose (0.5–10.0 μM and 0.01–10.0 mM) with the correlation coefficient of 0.99. The detection limit of glucose in PBS saline solution has been determined to be 445.7 (±10.3) nM.