Cyclodextrin based microcapsules and gels

Abstract

Microcapsules and hydrogels are two classes of functional materials that have recently arouse great interest. The former can be utilized as containers as an alternative to micelles and vesicles whereas the latter have been used for many biomedical applications such as drug delivery devices and tissue engineering. In this study, based on the host-guest complexation ability of cyclodextrins, fabrication of new microcapsules and functionalizable hydrogels was examined. In the first part, adamantane and cyclodextrin functionalized gold nanoparticles were synthesized for making microcapsules by supramolecular interactions. As a result of specific non-covalent interactions between the adamantyl and cyclodextrin ligands on the nanoparticle surfaces, crosslinking occurs at the interface of water/toluene emulsion. Resulting microcapsules were characterized using a variety of techniques such as optical, fluorescence and transmission electron microscopy. Furthermore, it was shown that the microcapsules were transferrable into aqueous phase. In the second part, by using click chemistry a new cyclodextrin based hydrogel was synthesized. The hydrogel can be functionalized both non-covalently by specific hydrophobic interactions and covalently by click chemistry. Besides, the hydrogel was successfully patterned on silicon and glass substrates by micromolding in capillaries technique.