How low does the oxygen concentration go within a sandwich-type amperometric biosensor?

MARCELO ROMERO; ANA BARUZZI; FERNANDO GARAY

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2012 vol. 174 p. 279 - 279

oftware for the automatic non-linear least squares fit of chronoamperometric responses correspondingto sandwich-type amperometric biosensors has been developed. The so-called Simplex algorithm computesa minimum value for the difference between experimental and theoretical data. The latter considera numerical model based on a ping-pong reaction mechanism corresponding to an oxidase enzyme thathas been immobilized between diffusion membranes.The results obtained from the simulation of a first-generation lactate biosensor in presence of 0.1 mMsubstrate indicate that the concentration of O2 would decrease only 0.1% with regards to its bulk value.Besides, the concentration of this natural mediator would remain practically unchanged during a typicalcalibration curve. This is because the rather high diffusion coefficient of O2 and its regeneration at theelectrode surface minimize the concentration changes of this species. In addition, it