Inclusion Complexes of Folic Acid with Polyamine-Modified β-Cyclodextrins: Characterization, Solubilization and Inclusion Mode

摘要

The formation of inclusion complexes between folic acid with three types of polyamine-modified β-cyclodextrins (1-3) was studied in solution and steady state by means of fluorescence spectroscopy, NMR, XRD and DSC. The stoichiometric ratio and stability constant was determined by Job's plot and fluorescence titrations method, respectively. The results showed that 1:2 complexes are formed for folic acid with hosts β-cyclodextrins (1-3). From the ROES Y data, benzene ring and pteridine ring of folic acid was found to be inserted to the cavity of β-cyclodextrin. Due to excellent enhancement of water solubility and thermal stability of folic acid with addition of hosts (1-3), this study will provide useful information for its application as herbal medicine.