Preparation of nano- and microstructures through molecular assembly of cyclic oligosaccharides

Abstract

The shape, size, and size distribution of nano- and microstructures formed by the self-assembly of small molecules are crucial factors that govern their chemical and physical properties. Understanding these factors can reveal the correlations between the supramolecular structure and the emergent properties and may realize innovative new materials. Hence, the formation processes and syntheses of nano- and microstructures consisting of various functional molecules have been actively studied. Herein, we report the bottom-up preparation and functions of nano- and microstructures formed by the self-assembly of cyclodextrins (CDs), which are cyclic oligosaccharides. Reprecipitation and electrospinning methods produce various supramolecular structures based on CDs. The assembly modes of CD molecules and their morphologies remarkably affect the properties and functions of the supramolecular structures. In particular, γ-CD-based supramolecular structures achieve the inclusion of guest molecules dissolved in oils, which is difficult to achieve with a single-CD molecule. Furthermore, cubic γ-CD structures show excellent dispersibility in oils, forming organogels in various oils, and organic solvents at ambient temperature. These studies indicate that the construction and morphological control of self-assembled CD structures can effectively realize the potential function of CD molecules and open new fields in oligosaccharide chemistry and supramolecular chemistry.