Rotating bioreactor based on an electron transfer mediated by osmium complexes incorporating continuous-flow/stopped -flow system. Application to the determination of glucose in serum samples

A. LAPIERRE; F. BATTAGLINI; J. RABA

ANALYTICA CHIMICA ACTA

Elsevier

Lugar: Amsterdam; Año: 2001 vol. 443 p. 17 - 24

0003-2670

A recently introduced redox osmium complex of the type [Os(bpy)2Cl(pyX]+, where pyX corresponds to a pyridine derivative bearing an aldehyde group, and glucose oxidase [EC 1.1.3.4] were covalently immobilized on the glassy carbon electrode surface (upper cell body). This approach has been designed in a sealed cell to be used under continuous-flow/stopped-flow/continuous-flow processing. The operating characteristic of the integrated bioreactor/detector unit has been utilized in the determination of glucose in serum samples using the electroactive polymer as mediator in the re-oxidation of GOx and amperometric monitoring. The determinations are based on the rate of response under stopped-flow conditions. The trend in values of the apparent Michaelis–Menten constant confirms the validity of the approach to sensitive determination utilizing very small amounts of biocatalysts. The determination of glucose was possible with a limit of detection of 0.020 mM in the processing of as many as 30 samples per hour.