Spectral and Photoprototropic Characteristics of 4-Aminobiphenyl in β-Cyclodextrin

2004 ◽  
Vol 69 (4) ◽  
pp. 748-758 ◽  
Author(s):  
Israel V. Muthu Vijayan Enoch ◽  
Meenakshisundaram Swaminathan

The photophysical and photoprototropic behaviour of 4-aminobiphenyl (4ABP) in aqueous β-cyclodextrin (β-CDx) solution has been investigated using steady-state and time-resolved fluorescence spectroscopy. Fluorescence of the neutral form of 4ABP is enhanced due to the formation of a 1:1 complex with β-CDx. The formation of this complex has been confirmed by time-resolved spectroscopy. In the presence of β-CDx, no change was observed in the ground state pKa value but the excited state pKa value changed. Based on its photophysical and photoprototropic characteristics in β-CDx, the structure of the 1:1 inclusion complex is proposed.

2010 ◽  
Vol 8 (3) ◽  
pp. 674-686 ◽  
Author(s):  
Magda Milewska ◽  
Katarzyna Guzow ◽  
Wiesław Wiczk

AbstractThe ability of new chelate ligands, benzoxazol-5-yl-alanine derivatives substituted in position 2 by heteroaromatic substituent, to form complexes with selected metal ions in acetonitrile are studied by means of absorption and steady-state and time-resolved fluorescence spectroscopy. Among the ligands studied, only azaaromatic derivatives form stable complexes with transition metal ions in the ground state. Their absorption bands are bathochromically shifted enabling to use those ligands as ratiometric sensors. The fluorescence of each ligand is quenched by metal ions, however, in the presence of Cd(II) and Zn(II) ions a new red shifted emission band is observed.


2016 ◽  
Vol 18 (41) ◽  
pp. 28564-28575 ◽  
Author(s):  
Kazuki Furukawa ◽  
Norifumi Yamamoto ◽  
Kazuyuki Hino ◽  
Hiroshi Sekiya

Excited-state dynamics of 4′-N,N-dimethylamino-3-hydroxyflavone doped in acetonitrile crystals has been investigated by using steady-state and time-resolved fluorescence spectroscopy.


1985 ◽  
Vol 240 (2) ◽  
pp. 781-791 ◽  
Author(s):  
E.A. Permyakov ◽  
A.V. Ostrovsky ◽  
E.A. Burstein ◽  
P.G. Pleshanov ◽  
Ch. Gerday

1994 ◽  
Vol 48 (5) ◽  
pp. 630-637 ◽  
Author(s):  
Ming Li ◽  
Michaeleen L. Pacholski ◽  
Frank V. Bright

Poly(hexafluoropropylene-co-tetrafluoroethylene) (FEP) has been widely used in biotechnology because of its unique surface properties and biocompatibility. Recent work from our group has shown that plasma discharge-modified FEP can be used as the substratum for development of a very stable immunosensor. This result has prompted us to study further this new surface under ambient conditions. In this paper, we report on the covalent immobilization of a pyrene residue (-Py) onto FEP-APS (FEP-aminopropyl silane) surfaces and the characterization of FEP-APS-Py using steady-state and time-resolved fluorescence spectroscopy. Among the immobilization schemes tested, we found that the covalent coupling of pyrene-sulfonyl chloride to FEP-APS is the easiest and yields the most photostable FEP-APS-Py derivative. Steady-state emission spectra of FEP-APS-Py in contact with H2O, β-cyclodextrin (β-CD), and sodium dodecylsulfate (SDS) aqueous solutions differ considerably from those of Py-SO3 in solution. Time-resolved fluorescence spectroscopy of FEP-APS-Py demonstrates that the decay kinetics are strongly affected by the presence of ionic quenchers and molecular oxygen, as well as β-CD and SDS. The results are consistent with the suggestion that the APS-Py moiety undergoes a slow time-dependent reconfiguration at the FEP/APS interface.


2008 ◽  
Vol 12 (12) ◽  
pp. 1232-1241 ◽  
Author(s):  
Farid Aziat ◽  
Régis Rein ◽  
Jorge Peón ◽  
Ernesto Rivera ◽  
Nathalie Solladié

In this paper we now report our ongoing progress in the preparation of artificial photosynthetic systems through the preparation of light harvesting multi-porphyrins. A tetramer, constituted of a central dipeptide functionalized by two free-base porphyrins and surrounded by one amino-acid bearing a pendant Zn ( II ) porphyrin on each side, has been chosen. The optical and photophysical properties of this tetramer have been studied by absorption and fluorescence spectroscopy. In addition, the energy transfer phenomenon has been studied and monitored by femtosecond time-resolved fluorescence. Our results indicate that the excited state dynamics redounding in the excitation being localized in the inner free-base porphyrins takes place in the time scale of approximately 1 ps.


Sign in / Sign up

Export Citation Format

Share Document