Modelling a Peroxidase-based Fluorescent Biosensor

The paper presents a one-dimensional-in-space mathematical model of a peroxidase-based fluorescent biosensor. The mathematical model is based on a system of nonlinear reaction diffusion equations. The problem was solved numerically using finite difference technique. The model was used to study the effect of biosensor parameters, namely the thickness of the enzyme layer and the outer substrate concentration, on the response of the biosensor and it’s sensitivity. The performed calculations showed a complex influence of the substrate and hydrogen peroxide concentrations. INTRODUCTION Biosensors are analytical devices converting a biochemical recognition reaction into a measurable effect (Scheller and Schubert, 1992; Turner et al., 1987). They are applied widely to monitor chemical substances in the medicine, food technology and the environmental industry (Wollenberger et al., 1997). Optical biosensors based on the fluorescence detection generate a photoluminescent signal indicative of target analyte binding (Ligler and Taitt, 2002). Fluorescence emission is then detected and converted into an analytical signal (Knopf and Bassi, 2007). They have been used for the analysis of many chemical and biological substances, especially in cases limited by low analyte concentrations (Atwood and Steed, 2004). The mathematical model of optical biosensors has been very recently developed (Baronas et al., 2007a). However, the model was based upon absorbance measurements. In this report, a mathematical model for fluorescent biosensors is described. The model is used to predict the response of biosensor with varying physical and chemical characteristics.