Youdan Wang1, Pratixa P. Joshi, and David W. Schmidtke2. (1) School of Chemical, Biological, and Materials Engineering, University of Oklahoma, 100 East Boyd, SEC T-217, Norman, OK 73019, (2) School of Chemical, Biological and Materials Engineering, University of Oklahoma, 100 E. Boyd, Room T335, Norman, OK 73019
Glucose biosensors were fabricated by alternate immersion of gold electrodes in solutions of a positively charged redox polymer, poly[(vinylpyridine)Os(bipyridyl)2Cl2+/3+] and a negatively charged enzyme, glucose oxidase (GOX) or a GOX solution containing single-walled carbon nanotubes (SWNTs). The layer-by-layer assembly of the multilayer films were characterized by UV-vis spectroscopy and cyclic voltammetry, while characterization of the single-walled nanotubes was performed with transmission electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy. When the glucose oxidase solution contained single-walled carbon nanotubes (SWNTs) the oxidation peak currents during cyclic voltammetry increased 1.4 - 4.0 times as compared to films without SWNTs. Similarly the glucose electro-oxidation current also increased (6-17 times) when SWNTs were present. By varying the number of multilayers, the sensitivity of the sensors could be controlled.