Inclusion Compound from a Semifluorinated Alkane and β-Cyclodextrin

Abstract

Inclusion compounds (ICs) were obtained for the first time from a semifluorinated n-alkane (F(CF2)8(CH2)16H, abbreviated F8H16) with β-cyclodextrin (β-CD) in water. Because of the hydrophobic nature of the two constituent blocks, the semifluorinated alkane readily penetrates the hydrophobic CD's cavity, to avoid contact with water, and produces a fine crystalline powder. The crystalline ICs were studied through differential scanning calorimetry, Fourier transform infrared spectroscopy, X-ray diffractometry, and atomic force microscopy, and they were identified as novel systems, with different structure and behavior from the two parent molecules. According to X-ray diffractometry, the host−guest system presents the channel type structure that is typical of polymer−CD inclusion compounds. Atomic force microscopy confirms the presence of tubular structures obtained from dispersion of the F8H16/β-CD inclusion compound. The formation of such supramolecular assemblies may be useful for the encapsulation of fluo...