TY - JOUR
T1 - TIME‐RESOLVED FLUORESCENCE OF NITROBENZOXADIAZOLE‐AMINOHEXANOIC ACID
T2 - EFFECT OF INTERMOLECULAR HYDROGEN‐BONDING ON NON‐RADIATIVE DECAY
AU - Lin, Su
AU - Struve, Walter S.
N1 - Copyright:
Copyright 2016 Elsevier B.V., All rights reserved.
PY - 1991/9
Y1 - 1991/9
N2 - The fluorescence kinetics of the nitrobenzoxadiazole (NBD) chromophore were studied at low concentrations in solvents with varying polarity and hydrogen‐bonding donor strength. The emission decay was essentially single exponential in all solvents studied. While the absorption and fluorescence solvatochromism is determined largely by the solvent polarity, the S, state decay kinetics are strongly modulated by the solvent H‐bonding capacity. The NBD emission lifetime, generally –7–10ns in the aprotic solvents, is reduced to 0.933 ns in water. The solvent deuterium isotope effect on the fluorescence decay is substantial in D20 and in methanol‐d4, but is insignificant in DMSO‐d6. These results are consistent with acceleration of S1S11 internal conversion through an accepting vibrational mode created by intermolecular hydrogen‐bonding of the NBD chromophore to an H atom‐donating solvent. This work bears on the practicality of using NBD as a fluorophore in assays for estrogen and progesterone receptors.
AB - The fluorescence kinetics of the nitrobenzoxadiazole (NBD) chromophore were studied at low concentrations in solvents with varying polarity and hydrogen‐bonding donor strength. The emission decay was essentially single exponential in all solvents studied. While the absorption and fluorescence solvatochromism is determined largely by the solvent polarity, the S, state decay kinetics are strongly modulated by the solvent H‐bonding capacity. The NBD emission lifetime, generally –7–10ns in the aprotic solvents, is reduced to 0.933 ns in water. The solvent deuterium isotope effect on the fluorescence decay is substantial in D20 and in methanol‐d4, but is insignificant in DMSO‐d6. These results are consistent with acceleration of S1S11 internal conversion through an accepting vibrational mode created by intermolecular hydrogen‐bonding of the NBD chromophore to an H atom‐donating solvent. This work bears on the practicality of using NBD as a fluorophore in assays for estrogen and progesterone receptors.
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U2 - 10.1111/j.1751-1097.1991.tb02028.x
DO - 10.1111/j.1751-1097.1991.tb02028.x
M3 - Article
C2 - 1784635
AN - SCOPUS:0026212510
SN - 0031-8655
VL - 54
SP - 361
EP - 365
JO - Photochemistry and photobiology
JF - Photochemistry and photobiology
IS - 3
ER -