Voltage-sensitive fluorescence of amphiphilic hemicyanine dyes in a black lipid membrane of glycerol monooleate.
Amphiphilic fluorescent hemicyanine dyes were adsorbed to a hemispherical bimolecular membrane of glycerol monooleate. Their excitation spectra of fluorescence were as in water, their emission spectra were as in hydrocarbon. An AC-voltage was applied across the membrane and the relative changes of the spectra of excitation and of emission were recorded. For all dyes we observed a blue-shift of excitation with positive voltage on the opposite side of staining. The effect is compared with the blue-shift expected for electrochromism. For most dyes we observed a red-shift of emission and a drop of the fluorescence intensity. These effects are compared with the red-shift and the drop of quantum yield expected for a voltage-induced solvatochromism caused by a minute displacement of the dyes in the anisotropic environment at the membrane/water interface.
Fromherz
P
P
Abteilung Biophysik Universität Ulm, Germany.
Schenk
O
O
D005456:Fluorescent Dyes; D005989:Glycerides / Q000737:chemistry*; D008051:Lipid Bilayers / Q000737:chemistry*; D008564:Membrane Potentials; D011726:Pyridinium Compounds
D005456:Fluorescent Dyes; D005989:Glycerides; D008051:Lipid Bilayers; D011726:Pyridinium Compounds; C005953:monoolein