TY - JOUR
T1 - Unique photophysical behavior of 2,2′-Bipyridine-3,3′-diol in DMSO-water binary mixtures
T2 - Potential application for fluorescence sensing of Zn2+ based on the inhibition of excited-state intramolecular double proton transfer
AU - Mandal, Sarthak
AU - Ghosh, Surajit
AU - Banerjee, Chiranjib
AU - Kuchlyan, Jagannath
AU - Sarkar, Nilmoni
PY - 2013/10/10
Y1 - 2013/10/10
N2 - In this work we have investigated the anomalous behavior of DMSO-water binary mixtures using 2,2′-bipyridine-3,3′-diol (BP(OH)2) as a microenvironment-sensitive excited-state-intramolecular-double-proton- transfer (ESIDPT) probe. Here we present results on the UV-vis absorption and fluorescence properties of BP(OH)2 in the binary solutions. DMSO-water binary mixtures at various compositions are an intriguing hydrogen bonded system, where DMSO acts to diminish the hydrogen bonding ability of water with the dissolved solutes. As a result, we observe unusual changes in the photophysical properties of BP(OH)2 with increasing DMSO content in complete correlation with the prior simulation and experimental results on the solvent structures and dynamics. The fluorescence quantum yield and fluorescence lifetime of BP(OH)2 depend strongly on the DMSO content and become maximum at very low mole fraction (∼0.12) of DMSO. The anomalous behavior at this particular region likely arises from the enhanced pair hydrophobicity of the medium as demonstrated by Bagchi and co-workers (Banerjee, S.; Roy, S.; Bagchi, B. J. Phys. Chem. B 2010, 114, 12875-12882). In addition we have also shown the utilization of BP(OH)2 as a potential Zn 2+-selective fluorescent sensor in a 1:1 DMSO-water binary mixture useful for biological applications. We observed highly enhanced fluorescence emission of BP(OH)2 selectively for binding with the Zn2+ metal ion. Moreover, the fluorescence emission maximum of BP(OH) 2-Zn2+ is significantly blue-shifted with a reduced Stokes shift due to the inhibition of the ESIDPT process of BP(OH)2 through strong coordination.
AB - In this work we have investigated the anomalous behavior of DMSO-water binary mixtures using 2,2′-bipyridine-3,3′-diol (BP(OH)2) as a microenvironment-sensitive excited-state-intramolecular-double-proton- transfer (ESIDPT) probe. Here we present results on the UV-vis absorption and fluorescence properties of BP(OH)2 in the binary solutions. DMSO-water binary mixtures at various compositions are an intriguing hydrogen bonded system, where DMSO acts to diminish the hydrogen bonding ability of water with the dissolved solutes. As a result, we observe unusual changes in the photophysical properties of BP(OH)2 with increasing DMSO content in complete correlation with the prior simulation and experimental results on the solvent structures and dynamics. The fluorescence quantum yield and fluorescence lifetime of BP(OH)2 depend strongly on the DMSO content and become maximum at very low mole fraction (∼0.12) of DMSO. The anomalous behavior at this particular region likely arises from the enhanced pair hydrophobicity of the medium as demonstrated by Bagchi and co-workers (Banerjee, S.; Roy, S.; Bagchi, B. J. Phys. Chem. B 2010, 114, 12875-12882). In addition we have also shown the utilization of BP(OH)2 as a potential Zn 2+-selective fluorescent sensor in a 1:1 DMSO-water binary mixture useful for biological applications. We observed highly enhanced fluorescence emission of BP(OH)2 selectively for binding with the Zn2+ metal ion. Moreover, the fluorescence emission maximum of BP(OH) 2-Zn2+ is significantly blue-shifted with a reduced Stokes shift due to the inhibition of the ESIDPT process of BP(OH)2 through strong coordination.
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U2 - 10.1021/jp406853r
DO - 10.1021/jp406853r
M3 - Article
C2 - 24041157
AN - SCOPUS:84885643493
VL - 117
SP - 12212
EP - 12223
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
SN - 1520-6106
IS - 40
ER -