Wired Enzyme Electrodes for Amperometric Determination of Glucose or Lactate inthe Presence of Interfering Substances. (Reannouncement with New Availability Information)

摘要

Glucose oxidase (GOX) or lactate oxidase (LOX) were immobilized in an osmium-based three-dimensional redox hydrogel that electrically connected the enzyme's redox centers to electrodes. The enzyme 'wiring' hydrogel was formed by cross-linking poly(1-vinylimidazole) (PVI) complexed with Os(4,4'-dimethylbpy)2C1 (termed PVI 15-dmeOs) with poly(ethylene glycol) diglycidyl ether (peg). Glucose and lactate sensors exhibited typical limiting current densities of 250 and 500 micro A/sq cm respectively. When the electrodes were poised at 200 mV (SCE), the currents resulting from electrooxidation of ascorbate, urate, acetaminophen, and L-cysteine were negligible. When a Nafion film was employed, the linear range was extended from 6 to 30 mM glucose and from 4 to 7 mM lactate. The redox potential of the gel-forming polymer was 95 mV (SCE). Glucose and lactate measurements performed in bovine calf serum correlated well with a substrate calibration in phosphate buffer. Enzyme, Electrodes, Glucose, Lactate.