Enhancement effect of Ag-Au nanoparticles on glucose biosensor sensitivity

Hydrophobic Ag-Au nanoparticles are produced in AOT [Aeroslo OT, sodium bis (2-ethyhexyl) sulfosuccinate]-cyclohexane reverse micellar system. Glucose biosensors have been formed with glucose oxidase (GOD) immobilized in composite immobilization membrane matrix, which is composed of hydrophobic Ag-Au particles and polyvinyl butyral (PVB) by a sol-gel method. The experiments show that nanoparticles can significantly enhance the catalytic activity of the immobilized enzyme. The current response is increased from tens of nanoamperometer (nA) to ten thousands of nanoamperometer to the same glucose concentration. The experiment and theory proved the function of nanoparticles in immobilization of enzyme. The catalysis of enzyme improved by nanoparticles was discussed. This research provides experimental and theoretical basis for preparation of useful glucose biosensor.