Freeze-dried complexes of furosemide with beta-cyclodextrin derivatives

A freeze-drying method was used to prepare complexes of furosemide (guest) with three derivatives of beta-cyclodextrin (hosts) in different molecular ratios in order to increase the aqueous solubility and rate of dissolution of the drug, and also to study the influence of this method on different pa rameters of the guest and the host, such as the diffusion rate constant and the partition coefficient, and additionally the surface tension activity o f the host (if any). The hosts were found to have significant, increasing e ffects on the solubility and the rate of dissolution of furosemide. X-ray d iffraction confirmed the host-guest interaction, in support of the earlier results. The freeze-drying method increased the diffusion rate of the drug in complex form, while the partition coefficient varied with the type of be ta-cyclodextrin in the product. It is well known that CD derivatives are hi ghly surface active which gives rise to their hemolytic action. Our observa tions showed that their presence with furosemide in complex form might decr ease (if not diminish) the hemolytic action.