Studies of Cyclodextrin Inclusion Complexes. II.1) Application of the Partition Coefficient Method

Abstract

The behavior of 1:1 inclusion complexes between cyclodextrins (CyD) and bencyclane (Ben) in a two-liquid-phase system of octanol and water was quantitatively investigated by measurement of partition coefficients (PC method). It was found that octanol partially prevents the formation of CyD-Ben complex and the apparent formation constant (K′) was calculated from the apparent partition coefficient (P*). This phenomenon was also observed in general with CyD 1:1 inclusion complexes of various drugs. The corrected formation constants (K) of these complexes in the aqueous phase were determined from the K′ values by applying the equilibrium equations. © 1984, The Pharmaceutical Society of Japan. All rights reserved.