Abstract
The molecular recognition interaction of beta-cyclodextrin (beta-CDx) was investigated using 2-amino-9-fluorenone (2AFN) by UV, steady-state fluorescence and time-resolved fluorescence measurements in aqueous solution at various pH. The effect of acidity on the ground and excited state equilibria between the neutral and the monocationic forms of 2AFN in water and in beta-CDx environments are studied. Based on the change in the fluorescence spectrum and lifetimes of 2AFN by the addition of beta-CDx, it is found that the unsubstituted part of the 2AFN is encapsulated in the hydrophobic cavity of beta-CDx. The unusual red shift obtained for the protonation of amino group in water and beta-CDx solution is due to large solvent relaxation of the monocation. The structure of the 1:1 inclusion complex between 2AFN and beta-CDx has been proposed on the basis of ground and excited state pKa values and the bond distances obtained by MOPAC/AM 1 data.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.