[Physical and chemical characterization of allantoin-beta-cyclodextrin inclusion complex].

Solubility and bioavailability of poorly water-soluble drugs have been improved by the preparation as cyclodextrin inclusion complexes. The aim of this study is to obtain and characterize the inclusion compound allantoin-beta-cyclodextrin. Allantoin is a vegetable drug, poorly water-soluble (1:300), isolated from roots of Symphytum off. The solid inclusion complex was prepared by mixing with a adequate quantity of water and drying at 50 degrees C to the constant weight. It was used a different proportions between allantoin and beta-cyclodextrin (1:4, 3:7). The inclusion complex was characterized with RMN and IR spectrum and compared with results obtained from beta-cyclodextrin and allantoin alone. The experimental results were demonstrated the inclusion of allantoin in the lipophilic cavity of beta-cyclodextrin without physico-chemical changes.