Engineered Pt-Doped Nanoceria for Oxidase-Based Bioelectrodes Operating in Oxygen-Deficient Environments

The use of Pt-doped nanoceria as a new catalytic amplification system for first-generation electrochemical oxidase-based biosensors is described. The catalytic activity and oxygen-rich surface of nanoceria, combined with the high conductivity of noble-metal Pt electrocatalysts, provide enhanced performance characteristics of mediatorless glucose oxidase biosensors for the detection of glucose in oxygen-deficient environments. The Pt-doped nanoceria particles act as both an internal oxygen reservoir to satisfy the oxygen requirement for the enzymatic reaction and a catalytic amplification system for the detection of enzymatically generated H2O2. The biosensor allows detection of glucose in anaerobic conditions with a detection limit of 37.4 mu m. The proposed strategy can be widely applicable to other oxidase-based biosensors that require measurements of their substrates in oxygen-deficient conditions.