(576h) Fractal Binding and Dissociation Kinetics of Prion Proteins on Biosensor Surfaces

A fractal analysis is presented for the binding and the dissociation of prion proteins to biosensor surfaces. Both single-and dual-fractal analysis may be used to model the binding and the dissociation kinetics. The fractal dimension provides a quantitative measure of the degree of heterogeneity on the biosensor surface. The binding and dissociation of human Clq in solution to PrP immobilized on a sensor chip surface is analyzed [11]. Quantitative relations are presented for (a) the binding rate coefficient, k as a function of the Clq in solution, (b) the dissociation rate coefficient, kd as a function of the Clq in solution, (c) the affinity, K(=k/ kd ) as a function of the ratio of the fractal dimensions present in the binding and in the dissociation phase Df/Dfd, and (d) the affinity K as a function of the Clq concentration in solution. These relationships developed provide fresh physical insights into the interactions of prion proteins on biosensor surfaces and into these types of reactions in general.