Coimmobilization of pyranose dehydrogenase as an enzyme catalyst, osmium redox polymers [Os(4,​4'-​dimethoxy-​2,​2'-​bipyridine)​2(poly(vinylimidazole)​)​10Cl]​+ or [Os(4,​4'-​dimethyl-​2,​2'-​bipyridine)​2(poly(vinylimidazole)​)​10Cl]​+ as mediators, and carbon nanotube conductive scaffolds in films on graphite electrodes provides enzyme electrodes for glucose oxidn. The recombinant enzyme and a deglycosylated form, both expressed in Pichia pastoris, are investigated and compared as biocatalysts for glucose oxidn. using flow injection amperometry and voltammetry. In the presence of 5 mM glucose in phosphate-​buffered saline (PBS) (50 mM phosphate buffer soln., pH 7.4, with 150 mM NaCl)​, higher glucose oxidn. current densities, 0.41 mA​/cm2, are obtained from enzyme electrodes contg. the deglycosylated form of the enzyme. The optimized glucose-​oxidizing anode, prepd. using deglycosylated enzyme coimmobilized with [Os(4,​4'-​dimethyl-​2,​2'-​bipyridine)​2(poly(vinylimidazole)​)​10Cl]​+ and carbon nanotubes, was coupled with an oxygen-​reducing bilirubin oxidase on gold nanoparticle dispersed on gold electrode as a biocathode to provide a membraneless fully enzymic fuel cell. A max. power d. of 275 μW​/cm2 is obtained in 5 mM glucose in PBS, the highest to date under these conditions, providing sufficient power to enable wireless transmission of a signal to a data logger. When tested in whole human blood and unstimulated human saliva max. power densities of 73 and 6 μW​/cm2 are obtained for the same fuel cell configuration, resp.