Dissolution Characteristics of Nifedipine Complexes with β-Cyclodextrins

Abstract

Formation of nifedipine complexes with β-cyclodextrin, hydroxypropyl-β-cyclodextrin, and DIMEB in solution was studied by the phase solubility method. Solid complexes of nifedipine were prepared by partial and complete solubilization of nifedipine using the freeze- and spray-drying techniques. The complexation led to an improvement in the dissolution rate of the drug. The relative potency of β-cyclodextrins to enhance the dissolution rate of nifedipine was in order: p-cyclodextrin < hydroxypropyl-β-cyclodextrin < DIMEB, which clearly fits the magnitude of stability constant data of the complexes. The dissolution rates of the free drug, complexes, and physical mixture of drug and cyclodextrins from constant surface area disks were also investigated.