β-Cyclodextrin hydrogels as potential drug delivery systems

Abstract

► Insoluble cyclodextrin polymers as discs with a controlled geometry have been synthesized. ► Interaction between the polymers and model drugs in the solid state canbe evidenced. ► Kinetic, diffusion constants and diffusion coefficients have been calculated. ► In vitro drug release studies followed a simple Fickian diffusion mechanism. ► The synthesized matrices are potentially suitable as sustained release systems. β-cyclodextrins (βCD) are cyclic oligosaccharides which have been widely employed for pharmaceutical applications. Discs of insoluble polymers were synthesized by crosslinking β-cyclodextrins with the reagent epichlorohydrin. In this work, the possibility of employing a polymer containing 60 ± 3% βCD for drug delivery of two antiinflammatory (naproxen and nabumetone) and two antifungal drugs (naftifine and terbinafine) has been investigated. The interaction of Naproxen with the polymers was evidenced by X-ray diffractometry, FTIR spectroscopy and differential thermal analysis. Drug release kinetics were carried out at physiological conditions of pH and temperature, and kinetic and diffusion constants were calculated by fitting 60% of the release profile according to the Korsmeyer–Peppas equation. Also, diffusion coefficients were calculated according to the simplified Higuchi model. The drug release followed a simple Fickian diffusion mechanism for all the model drugs. This study suggests that these hydrogel matrices are potentially suitable as sustained release systems.