Theoretical study of inclusion complex formation of cyclodextrin and single polymer chain

Abstract

We study the inclusion complex formation of cyclodextrins and a single polymer chain by a grand canonical Monte Carlo simulation and by a statistical-mechanical theory. The filling ratio of the polymer chain by threaded cyclodextrins is calculated and shows good agreement with reported experimental results. The adsorption isotherm of the filling ratio is also derived by the statistical-mechanical theory. We confirm the significance of hydrogen bonds between cyclodextrins for the inclusion complex formation. When hydrogen bonds can be formed between cyclodextrins, the filling ratio drastically increases at a certain concentration of the cyclodextrins, and inclusion complexes are formed. However, inclusion complexes are rarely formed without hydrogen bonds. We also find the expansion of size of the polymer chain with the development of one-dimensional aggregates constructed by threaded cyclodextrins along the polymer chain.