Hierarchical cage-frame type nanostructure of CeO2 for bio sensing applications: From glucose to protein detection.

Self-assembled hierarchical nanostructures are slowly superseding their conventional counterparts for use in biosensors. These morphologies show high surface area with tunable porosity and packing density. Modulating the interfacial interactions and subsequent particle assembly occurring at the water-and-oil interface in inverse miniemulsions, are amongst the best strategies to stabilize various type of hollow nanostructures. The paper presents a successful protocol to obtain CeO2hollow structures based biosensors that are useful for glucose sensing. The fabricated glucose sensor is able to deliver high sensitivity (0.495 μA cm-2nM-1), low detection limit (6.46 nM) and wide linear range (0 nM to 600 nM). CeO2based bioelectrode can also be considered as a suitable candidate for protein sensors. It can detect protein concentrations varying from 0 to 30 µM, which is similar or higher than most reports in the literature. The limit of detection (LOD) for protein was ~ 0.04 µM. Therefore, the hollow CeO2electrodes, with excellent reproducibility, stability and repeatability, opens a new area of application for cage-frame type nanoparticles.