[A conductometric enzymatic glucose sensor. A search for ways to improve analytical characteristics]. / Konduktometrychnyi fermentnyi gliukosensor. Poshuk shliakhiv polipshennia analitychnykh kharakterystyk.

Characteristics of conductometric enzyme glucosensor based on thin-film interdigitated electrodes have been studied. The obtained biosensor exhibits a linear dynamic range of 0.01-2 mM for glucose and sensitivity 5 microS/min*mM for kinetic mode of measurements and 8 microS/mM for steady-state mode of measurements. Additional 2% PVB- and NAFION-membranes are suggested for the extension of the dynamic range. This permits extending the dynamic range of the sensor up to glicose concentration of 10 mM. Dependence of activity of immobilized enzyme on ionic strength and buffer capacity of the solution has been studied. It was shown that formation of additional membranes results in the substantial reduction of the buffer concentration effect on the sensor response. The obtained results are interpreted in terms of permselective properties of the additional membrane formed.