A new osmium-polymer modified screen-printed graphene electrode for fructose detection

This paper describes the development and performance of the first fructose biosensor based on a commercial screen-printed graphene electrode (SPGE). The electrode was modified with an osmium-polymer, which allowed the efficient wiring of the enzyme fructose dehydrogenase (FDH). The immobilization of both osmium-polymer and FDH was realized in an easy way. Aliquots of 10 mu L, Os-polymer and 10 mu L, FDH were thoroughly mixed with poly(ethylene glycol) (400) diglycidyl ether (PEDGE) and deposited on the electrode surface and left there to dry overnight. The biosensor exhibits a detection limit of 0.8 mu M, a linear range between 0.1 and 8 mM, high sensitivity to fructose (2.15 mu A cm(-2)/mM), good reproducibility (RSD = 1.9%), fast response time (3 s) and a stability of 2 months when stored in the freezer. The proposed fructose biosensor was tested in real food samples and validated with a commercial spectrophotometric enzymatic kit. No significant interference was observed with the proposed biosensor. Published by Elsevier B.V.