Channel model for the theoretical study of aspirin adsorption on clinoptilolite. Water influence.

摘要

A new zeolite model, that represent the a and c channels of clinoptilolite have been used tostudy the possible interactions of aspirin-water-zeolite, in order to know the behavior of thedrug in a more complex system and the influence of water present in the zeolite channel. Thecalculations have been performed using the AM1 semiempirical method and acid and sodicclinoptilolite models. The results showed that the adsorption entalphy of aspirin in the acidstructure are in the same order that the obtained for the sodic structure, although the nature ofthe interaction is different in each structure. The ester and aromatic groups werepreferentially oriented to the model. In any case the chemical stability of aspirin is affectedby the presence of water molecules in the system.