β-Cyclodextrin inclusion complex: preparation, characterization, and its aspirin release in vitro

Abstract

In this work, the optimal clathration condition was investigated for the preparation of aspirin–β-cyclodextrin (Asp--β-CD) inclusion complex using design of experiment (DOE) methodology. A 3-level, 3-factor Box--Behnken design with a total of 17 experimental runs was used. The Asp--β-CD inclusion complex was prepared by saturated solution method. The influence on the embedding rate was investigated, including molar ratio of β-CD to Asp, clathration temperature and clathration time, and the optimum values of such three test variables were found to be 0.82, 49°C and 2.0 h, respectively. The embedding rate could be up to 61.19%. The formation of the bonding between--COOH group of Asp and O--H group of β-CD might play an important role in the process of clathration according to FT-IR spectra. Release kinetics of Asp from inclusion complex was studied for the evaluation of drug release mechanism and diffusion coefficients. The results showed that the drug release from matrix occurred through Fickian diffusion mechanism. The cumulative release of Asp reached only 40% over 24 h, so the inclusion complex could potentially be applied as a long-acting delivery system.

Keywords

β-cyclodextrin (β-CD) / aspirin (Asp) / saturated solution method / Box--Behnken design / release kinetics