Date of Award
Union College Only
Bachelor of Science
Cyclodextrins (CDs) are cyclical carbohydrates composed of repeating glucopyranose units. The three most common CDs, α-, β-, or y-, contain 6, 7 and 8 glucopyranose units, respectively, and have hydrophilic exteriors, which makes them water soluble. CD polymers (CDPs) have been synthesized, containing glyceryl link, between CD units. These polymers are more water soluble than their monomer counterparts. CDs and CDPs, because of their hydrophobic interior cavities, form inclusion complexes with various molecules, including aromatics. This latter property is one we have investigated using fluorophores, including naphthalenes and pyrene. We have shown, through absorption spectral and fluorescence lifetime data, that naphthalene forms a different type of complex with α-CDP than α-CD. We suggest this complex is 1:1, as the α-CD/naphthalene complex has been reported to be 2:1. We have also studied the binding of pyrene with β-CD derivatives. These derivatives have different substitution patterns, with substitution on the smaller rim of the β-CD cavity, the larger rim of the cavity, and on both rims of the cavity. We have shown, through steady-state fluorescence and fluorescence lifetime measurements, that the derivative with substitution on the smaller rim behaves similarly to β-CD. This suggests that a 2:1 complex is still forming, as reported in the literature. On the other hand, derivatives with at least some substitution on the larger rim behave more like the β-CDP. We suggest that larger rim substitution has two effects: A) the groups extend the hydrophobic cavity and B) a 1:1 complex is likely, as the groups seem to sterically hinder a 2:1 complex from forming.
McIntosh, Sara L., "A binding investigation of fluorescence\probes and cyclodextrin derivatives" (1997). Honors Theses. 2063.