NotesFAQContact Us
Search Tips
Peer reviewed Peer reviewed
Direct linkDirect link
ERIC Number: EJ825819
Record Type: Journal
Publication Date: 2008-Mar
Pages: 4
Abstractor: As Provided
Reference Count: 16
ISSN: ISSN-0021-9584
Supramolecular Inclusion in Cyclodextrins: A Pictorial Spectroscopic Demonstration
Haldar, Basudeb; Mallick, Arabinda; Chattopadhyay, Nitin
Journal of Chemical Education, v85 n3 p429-432 Mar 2008
A spectroscopic experiment is presented that reveals that the hydrophobically end-modified water-soluble polymeric fluorophore, pyrene end-capped poly(ethylene oxide) (PYPY), interacts differently with [alpha], [beta], and [gamma]-cyclodextrins (CD) to form supramolecular inclusion complexes. The emission spectrum of PYPY in aqueous solution shows characteristic dual emission; the pyrene monomer emission and the excimer emission. [alpha]-CD does not affect the absorption and emission spectra of the fluorophore. In [beta]-CD solution, the excimer emission yield decreases with a concomitant enhancement of the monomer emission while the fluorescence spectral observation in [gamma]-CD is qualitatively opposite. The differences in the photophysical behavior of the fluorophore in different CD environments establish different modes of encapsulation of PYPY in CDs with different cavity dimensions. The different modes of encapsulation are explained from the relative dimensions of the pyrene units and the various CD cavities. The cavity of [alpha]-CD is too small to form an inclusion complex with the fluorophore. [beta]-CD cavity has the proper dimension to encapsulate one pyrene unit of the polymer and [gamma]-CD cavity is large enough to include both the fluorophore end-groups in stacked orientation. (Contains 3 schemes and 2 figures.)
Division of Chemical Education of the American Chemical Society. Subscription Department, P.O. Box 1267, Bellmawr, NJ 08099-1267. Tel: 800-691-9846; Tel: 856-931-5825; Fax: 856-931-4115; e-mail:; Web site:
Publication Type: Journal Articles; Reports - Descriptive
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A