Cyclodextrins as Supramolecular Hosts for Dye Molecules

Cyclodextrins possess a hydrophobic cavity due to which they are suitable for inclusion of various organic dyes. The complex formation between CDs and dyes has been employed to affect the photophysical and photochemical characteristics of organic dyes such as fluorescence enhancement, charge and proton transfer, energy transfer, photochromic transformations and intramolecular excimer/exciplex formation. This fundamental approach has also potential nanotechnological application in creation of optoelectronic devices. Thus, the fluorescent hybrid nanomaterials consisting of supramolecular assemblies of cyclodextrins with fluorescent dyes can be considered as multivalent scaffolds for the construction of various devices applicable in science and technology, in fluorescence spectroscopic and microscopic techniques providing high sensitivity and imaging of cells with high resolutions. In some cases, fluorescent hybrid materials composed of CD-dye complexes have been successfully used instead of the fluorescent organic molecules in sensing and bioimaging studies.