β-Cyclodextrin Derivatives as Fluorescence Enhancers of the Drug, Hesperidin

Abstract

The fluorescence behavior of the drug hesperidin in several cyclodextrins(CDS):β-cyclodextrin(β-CD), hydroxypropyl-β-CD (HP-β-CD) and methyl-β-CD(M-β-CD) was studied. The stoichiometry of the complexes and their apparent formation constants were estimated. The excitation wavelengths were at 335nm for hesperidin in β-CD, HP-β-CD and M-β-CD media. The emission wavelengths were at 444, 436 and 434 nm, respectively; The fluorescence enhancement of hesperidin was observed in different cyclodextrin media. The linear calibration plots between fluorescence intensity and hesperidin concentration were determined in the 10⁻⁷ ∼10⁻⁵ M range. The mechanism for the enhanced fluorescence was attributed to protection of the excited state within the cyclodextrin cavity.

Key Words:

• Cyclodextrin
• Inclusion complexes
• Hesperidin