Au@Pt core/shell nanorods with peroxidase- and ascorbate oxidase-like activities for improved detection of glucose

Au nanorods @ Pt nanodots core/shell nanostructures, prepared by the Au nanorods (NRs)-mediated growth, exhibit dual functional enzyme-like (peroxidase and oxidase-like) activities. From the viewpoint of enzyme mimics, the relationship between apparent enzyme kinetic parameters and nanomaterials structure is investigated in order to rationally design the catalytic activity. Using peroxidase-like properties of the Au@Pt NRs, the determination of hydrogen peroxide (H2O2) was demonstrated with a limit of detection (LOD) 01 4.5 x 10(-5) M and a linear range of 4.5 x 10(-5)-1 X 10(-3) M using o-phenylenediamine (OPD) as chromogenic substrate. Furthermore, in combination with highly specific reactions provided by natural enzymes, selective detections of glucose and lipophilic cholesterol were demonstrated with similar LODs and linear ranges. Additionally, owing to the specific oxidase-like activity of the Au@Pt NRs (ascorbate oxidase), interference of ascorbic acid in the detection of glucose could be eliminated. In conclusion, considering the flexibility in the design of nanomatererials, there is a lot of space to improve their activity and explore their potential applications, especially in relatively harsh conditions. (C) 2012 Elsevier B.V. All rights reserved.