title: Fluorescence Dynamics of Monocyclodextrin- and Bis(thiol-cyclodextrin)-Coumarin C153 Complexes.
abstract: The solvation and confinement of coumarin C153 within supramolecular host/guest complexes based on β-cyclodextrin (β-CD) and 6-deoxy-6-thio-β-cyclodextrin (β-CD-SH) in water are studied by fluorescence spectroscopy. For β-CD/C153, the 1:1 complex is proposed, and for β-CD-SH/C153 both the 1:1 and 2:1 complexes are believed to be formed. The 2:1 β-CD-SH/C153 complex has an association constant of 4.2×10(5)  M(-1) and a C153 population of 82 %, which are interestingly high values, indicating that the proposed β-CD-SH dimers structure are connected by covalent disulfide bonds; this is supported by mass spectrometry. Solvation related to fast hydrogen-bond rearrangement as a part of fluorescence relaxation is determined by the ultrafast components of time-resolved spectroscopy to be 3 and 7 ps for the 1:1 β-CD/C153 and 2:1 β-CD-SH/C153 complexes, respectively.
authors.affiliation: Department of Physical and Theoretical Chemistry, Comenius University, Mlynska dolina, Bratislava (Slovakia). trencanova@fns.uniba.sk.
authors.forename: Marianna Gregova
authors.initials: MG
authors.lastname: Trencanova
authors.affiliation: International Laser Center, Ilkovicova 3, Bratislava (Slovakia).
authors.forename: Eduard
authors.initials: E
authors.lastname: Jane
authors.affiliation: Institue of Chemistry, Comenius University, Mlynska dolina, Bratislava (Slovakia).
authors.forename: Vojtech
authors.initials: V
authors.lastname: Szocs
authors.affiliation: Department of Physical and Theoretical Chemistry, Comenius University, Mlynska dolina, Bratislava (Slovakia).
authors.forename: Sona
authors.initials: S
authors.lastname: Halaszova
authors.affiliation: Department of Physical and Theoretical Chemistry, Comenius University, Mlynska dolina, Bratislava (Slovakia).|International Laser Center, Ilkovicova 3, Bratislava (Slovakia).
authors.forename: Monika
authors.initials: M
authors.lastname: Jerigova
authors.affiliation: International Laser Center, Ilkovicova 3, Bratislava (Slovakia).
authors.forename: Ludovit
authors.initials: L
authors.lastname: Haizer
authors.affiliation: Department of Physical and Theoretical Chemistry, Comenius University, Mlynska dolina, Bratislava (Slovakia).|International Laser Center, Ilkovicova 3, Bratislava (Slovakia).
authors.forename: Dusan
authors.initials: D
authors.lastname: Velic
keywords: coumarin C153; cyclodextrins; fluorescence; supramolecular chemistry; thiols