Modelling of Amperometric Biosensors in the Case of Substrate Inhibition

Sensors

Juozas Kulys¹ 

[1] Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Sauletekio al. 11, 10223 Vilnius, Lithuania

关键词: biosensor;    enzyme inhibition;    diffusion;    modelling;   

DOI  :  10.3390/s6111513

来源: mdpi

【 摘 要 】

The response of an amperometric biosensor at mixed enzyme kinetics and diffusion limitations was modelled digitally in the case of substrate inhibition. Digital simulations were carried out using a finite difference technique. Calculations showed complex kinetics of biosensor response. At low enzyme activity and substrate concentration (S₀), the response of the sensor looks like it is limited by a simple substrate diffusion. At substrate concentration comparable to the Michaelis-Menten constant (K_M), the response change shows a maximal value. A sharp response change was indicated at high enzyme activity and high (4.9 > S₀/K_M > 4.5) substrate concentration. This was explained by multi-concentration of substrate generation inside the enzyme layer. This conclusion was confirmed by the analytical solution of the simplified biosensor model with external diffusion limitation at steady-state conditions. The complex kinetics of response change produces different calibration graphs for biosensor response at transition and steady state.

【 授权许可】

Unknown   
© 2006 by MDPI (http://www.mdpi.org).