Cholesterol templated polymers : are they really specific binding materials?

The technique of molecular imprinting creates template specific and selective polymer products with a large assortment of applications. For example, molecularly imprinted polymers (MIPs) may pose as a means to separate undesirable components, such as endocrine disruptors, from the environment. Taking advantage of β-cyclodextrin's abililty to form inclusion complexes with a number of guests has led scientists to use them as scaffolds in the synthesis of MIPs. Komiyana's approach of molecularly imprinting cholesterol with β-cyclodextrin was used as a starting point to apply MIPs as potential tools for trapping endocrine disruptors. This study presents results on the re-binding of cholesterol to a cholesterol-templated MIP and to a non-MIP (NMIP), as well as the binding of a series of structurally unrelated compounds to the cholesterol-templated MIP and NMIP. The results consistently show that cholesterol-templated MIPs synthesized using Komiyama's method lack specificity and selectivity for their template. This calls into question their efficacy as a tool for trapping endocrine disruptors.