Kinetic Analysis for Analyte-Receptor Binding and Dissociation in Biosensor Applications: a Fractal Analysis

To acquire an understanding of biological processes at the molecular level requires two basic approaches: structural and functional analysis. Under ideal conditions these should complement each other and provide a complete picture of the molecular processes. Electron microscopy, sequence analysis, mass spectroscopy, X-ray and electron diffraction studies are routinely employed as structural techniques. These provide information about the atomic organization of individual as well as interacting biomolecules, but these have the disadvantage of being static and ’frozen’ in time. Functional investigation techniques like affinity chromatography, immunological techniques, and spectrophotometric techniques give valuable information on the conditions and the specificity of the interaction, but are (a) unable to follow a process in time, or (b) are too slow to be rendered suitable for most biospecific interactions. Moreover, these techniques demand some kind of labelling of interactants which is undesirable as it may interfere with the interaction and this will necessitate purification of the interactants in large quantities. A promising area in the investigation of biomolecular interactions is the development of biosensors. These biosensors are finding application in the areas of biotechnology, physics, chemistry, medicine, aviation, oceanography, and environmental control. These sensors or biosensors may be utilized to monitor the analyte—receptor reactions in real time (Myszka et al., 1997), besides some techniques like the surface plasmon resonance (SPR) biosensor do not require radiolabelling or biochemical tagging (Jonsson et al., 1991), are reusable, have a flexible experimental