Electrodeposited Cu-Au Alloy Nanoparticles for Uric Acid Electrochemical Biosensor with Quick Response

A uric acid (UA) electrochemical biosensor based on the Cu-Au alloy nanoparticles (NPs) and unease was developed. The electrodeposition technique of Cu-Au alloy NPs was selected to be a convenient potentiostatic method at -0.8 V in a single solution containing both Au(III) and Cu2+. Cyclic voltammetry and scanning electron microscopy proved the successful deposition of Cu-Au alloy NPs. EIS demonstrated the good conductivity of Cu-Au alloy NPs. The enzyme was immobilized on the surface of Cu-Au alloy NPs modified electrode by casting with chitosan solution. The ultimate biosensor showed linear amperometric response towards UA in the concentration range of 3.0 to 26.0 mu M with a detection limit of 0.8 mu M. The main feature of the biosensor was its short response time, which was attributed to the good conductivity of Cu-Au alloy NPs. Furthermore, the biosensor could avoid the interference of ascorbic acid and oxygen.