Three types of carbon-film electrodes, made from electrical resistors with 1.5-, 15-, and 140-Omega nominal resistances, were used to develop redox-mediated sol-gel biosensors, and the results were compared with those from previously investigated 2-Omega carbon-film electrodes. Two different redox mediators, copper hexa-cyanoferrate and poly(neutral red), were deposited onto the carbon-film electrodes, with the latter showing good electrochemical properties for electroanalytical applications, which were best on electrodes made from 15-Omega carbon-film resistors. It was not possible to deposit mediator film on the carbon-film resistor electrodes of 140-Omega nominal resistance. Glucose oxidase was immobilized on Poly(neutral red) modified electrodes with sol-gel encapsulation from a mixture of 3-glycidoxypropyltrimethoxysilane and methyltrimethoxysilane precursors at a volume ratio of 2 : 1. The best sensor electrochemical properties and response to glucose in model solution were found with electrodes constructed from 15-Omega resistors, although the stability under the same conditions was better ill the biosensors constructed with 2-Omega nominal resistance electrodes. (c) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112; 505-512, 2009