83683-58-3Relevant academic research and scientific papers
Fluorescence and Photoisomerisation of an Amphiphilic Aminostilbazolium Dye As Contolled by the Sensitivity of Radiationless Deactivation to Polarity and Viscosity
Ephardt, Heinz,Fromherz, Peter
, p. 7717 - 7725 (2007/10/02)
The dynamics of the first excited singlet state of (dibutylamino)stilbazolium butylsulfonate is investigated in various solvents.The lifetime and quantum yield of trans -> cis photoisomerization change by 2 orders of magnitude whereas the yield of cis -> trans photoisomerization is invariant.The environment affects an activated radiationless deactivation which competes with radiative decay and photoisomerization.The effect is assigned to the stabilization of a polar transition state in media of high dielectric constant (Born energy) and to friction along the reaction path in media of high viscosity (Kramers equation).Within such a model the isothermal data are compatible with the Arrhenius energies.The radiationless process is assigned tentatively to the formation of a twisted internal charge transfer state with fast internal convertion.Probing of fast changes of the electrical potential in biological membranes is discussed in the light of the photophysical properties of the dye.
Charge-Shift Probes of Membrane Potential. Synthesis
Hassner, A.,Birnbaum, D.,Loew, L. M.
, p. 2546 - 2551 (2007/10/02)
We are reporting two general synthetic approaches to a number of (aminostyryl)pyridinium dyes and their heterocyclic analogues which are of interest as electrochromic probes for membrane potential.The two routes which involve palladium-catalyzed coupling or aldol condensation permit considerable structure variations to be introduced in the dyes.Some spectral properties of the dyes are discussed.
