Amperometric Determination of Glucose with FeO and Glucose Oxidase Bulk-Modified Screen-Printed Carbon Ink Biosensor

Biosensor for amperometric determination of glucose was constructed by bulk-modification of carbon ink with iron (II) oxide FeO as a mediator and glucose oxidase as a biocomponent. The sensor could be operated in FIA (Flow Injection Analysis) mode at a working potential of - 200 mV versus the Ag/AgCl, flow rate of 0.5 mL min(-1) and carrier medium (0.1 mol L(-1) phosphate buffer, pH 7.5) exhibiting good reproducibility and stability. Glucose biosensor shows linear range within 10-200 mg L(-1) of glucose (i[mu A] = 5.17.10(-4)c[mg L(-1)] + 6.7.10(-4), r(2)=0.997), and detection limit (3 sigma) was found to be 2.8 mg L(-1). Biosensor was investigated for its ability for use as an amperometric detector for glucose in flow injection analysis (FIA) mode and as a detector for glucose in human blood. Results are in good matches with reference method results, obtained by commercial standard glucometer "Accu-Check Active".