Application of the Freundlich adsorption isotherm in the characterization of molecularly imprinted polymers

The binding isotherm for a polymer molecularly imprinted with ethyl adenine-9-acetate was observed to obey the common Freundlich isotherm. To test the generality of the Freundlich isotherm with respect to molecularly imprinted polymers (MIPs), a survey of systems from the literature was conducted, revealing that the Freundlich isotherm gives a good mathematical approximation of the binding characteristics for non-covalently imprinted polymers. The utility of the Freundlich isotherm in the calculation of binding parameters, as well as its limitations and implication of an exponential distribution of binding sites in imprinted polymers have been discussed.