Nanostructured glucose-oxidase immobilized SnO_2 thin films for glucose sensing

摘要

Polycrystalline rutile films of SnO_2 (~1500 Å) were deposited on Al_2O_3. Film imaging showed regular ellipsoidal nanostructured growth. Different concentrations (1000-3000 U) of glucose oxidase (GOx) were immobilized on SnO_2 surface. Upon interaction with various glucose concentrations (65-300 mg/dl), films showed pronounced change in their sheet resistance with recovery and repeatability. Nanostructured SnO_2 surfaces probably enhance adsorption of oxygen moieties. These convert to their ions by extracting electron/s from the conduction band of SnO_2, which further interacts with H~+, formed during the GOx-glucose interaction. This releases the trapped electron to the conduction band of SnO_2, justifying its role as a catalyst.