Excited-State Proton Transfer Dynamics of Firefly’s Chromophore D-Luciferin in DMSO–Water Binary Mixture
In this article we have investigated intermolecular excited-state proton transfer (ESPT) of firefly’s chromophore D-luciferin in DMSO–water binary mixtures using steady-state and time-resolved fluorescence spectroscopy. The unusual behavior of DMSO–water binary mixture as reported by Bagchi et al. (J. Phys. Chem. B 2010, 114, 12875–12882) was also found using D-luciferin as intermolecular ESPT probe. The binary mixture has given evidence of its anomalous nature at low mole fractions of DMSO (below XD = 0.4) in our systematic investigation. Upon excitation of neutral D-luciferin molecule, dual fluorescence emissions (protonated and deprotonated form) are observed in DMSO–water binary mixture. A clear isoemissive point in the time-resolved area normalized emission spectra further indicates two emissive species in the excited state of D-luciferin in DMSO–water binary mixture. DMSO–water binary mixtures of different compositions are fascinating hydrogen bonding systems. Therefore, we have observed unusual cha...
We recently generalized the formerly alignment-dependent multivariate image analysis applied to quantitative structure–activity relationships (MIA-QSAR) method through the application of the discrete Fourier transform (DFT), allowing for its application to noncongruent and structurally dive ... more
Poly-ADP-ribosylation (PARylation) is a protein posttranslational modification (PTM) that is critically involved in many biological processes that are linked to cell stress responses. It is catalyzed by a class of enzymes known as poly-ADP-ribose polymerases (PARPs). In particular, PARP1 is ... more
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Rohm and Haas Powder Coatings is delighted to announce that its Reading, Pennsylvania, facility is the first site in the world to receive the RCMS® Site Certification awarded by the American Chemical Council (ACC).
When Raj Gupta, Chairman and CEO of Rohm and Haas Company, became Chairman ... more