Non-enzymatic electrochemical glucose sensor based on monodispersed stone-like PtNi alloy nanoparticles

Monodisperse stone-like PtNi alloy nanoparticles (NPs) were synthesized at room temperature using an inverse microemulsion method. The results of XRD, HRTEM, and EDS demonstrate that these NPs consist of a disordered alloy that has (a) a face-centered cubic structure, (b) Pt/Ni atomic ratios of similar to 5:1, and (c) a large number of atoms exposed on the NP surface and enclosed by low index facets. The material was placed on a glassy electrode which then displayed superior response to glucose. Best operated at a potential of 0.43 V (vs. SCE), the electrode has the following features: (a) a wide linear range (from 0.5 mM to 40 mM), (b) rapid response (<1 s), (c) a low detection limit (0.35 mu M) and (d) a sensitivity of 40.17 mu A mM(-1)cm(-2)). The NP sensor also is fairly selective over ascorbic acid, uric acid and fructose. The sensor has repeatability and durability for up to 30 days after manufacture.