Testing the validity of the effective rate constant approximation for surface reaction with transport

AbstractWhen one incorporates transport effects into a surface-volume reaction, an integrodifferential equation for the bound state concentration occurs. Such a form is inconvenient for data analysis. An effective rate constant approximation for the solution is correct to O(Da2) as the Damköhler number Da → 0. A numerical simulation of the integrodifferential equation is performed which shows that the effective rate constant approximation is useful even outside this regime

The effect of receptor site nonuniformity on the measurement of rate constants

AbstractThe BIAcore is an instrument for measuring rate constants in real time by using a surface–volume geometry. Though current models for the resulting reaction include transport effects for the reactant in solution, they do not account for spatial nonuniformities in the reactant attached to the wall. This work accounts for such nonuniformities and establishes that in the limit of small Damköhler number, such effects are negligible due to the averaging characteristics of the instrumentation