Excited-state dynamics of the fluorescent probe Lucifer Yellow in liquid solutions and in heterogeneous media

Abstract

The photophysics of the dye Lucifer Yellow ethylenediamine (LYen) has been investigated in various polar solvents. The main deactivation pathways of its first singlet excited state are the fluorescence and the intersystem crossing. In water, non-radiative decay by intermolecular proton transfer becomes a significant deactivation channel. The early fluorescence dynamics, which was investigated in liquids and in reverse micelles, was found to depend substantially on the environment. An important static quenching of LYen by tryptophan and indole occurring in the subpicosecond timescale was observed. The use of the fluorescence dynamics of LYen as a local probe is illustrated by preliminary results obtained with a biotinylated Lucifer Yellow derivative complexed with avidin.

Ultrafast Excited-State Dynamics of Oxazole Yellow DNA Intercalators

“…17,18 To draw the decay-associated amplitude spectra, the sum of the positive amplitudes was set equal to 1 at 495 nm (maximum intensity in the spectrum). Time-resolved emission spectra were reconstructed from the analytical expressions obtained for the decays from the fitting procedure.…”

Design, Synthesis, Characterization and Toxicity Studies of Poly (N-Iso- Propylacrylamide-co-Lucifer Yellow) Particles for Drug Delivery Applications

“…Accordingly, a blue shift is observed when the fluorophore LY was incorporated into p(NIPAM). This is due to the change in the environment around the LY such as the electronic cloud in the polymer particle p(NIPAM) as well as the polarity of the solvent [18]. The shift of the emission band also provides evidence (together with the DLS and IR) of the incorporation of LY in the new nanoparticle.…”

“…However, the fluorescence intensity of LY is significantly higher than that of p(NIPAM-co-5% LY) which suggests that either not all the LY added during the synthesis reaction is incorporated in the new particle, or the quantum yield of LY was quenched by the p(NIPAM) particles, or other environmental conditions such as solvent polarity [18]. The second suggestion is supported by Furstenberg et al [18] who studied the excited state dynamics of lucifer yellow and concluded that LY is an environment sensitive probe whose fluorescence dynamics change in the presence of proteins and by changing the solvent. They also concluded that the fluorescence of LY is quenched by amino acids.…”

“…It is worth mentioning that the particle size of p(NIPAM)-co-5% LY decrease by 43% when the temperature increases from 25°C to 45°C at pH 3 and 7. The change in temperature can also cause a change in the quantum yield of fluorescence due to change in solvent properties such as solvent polarity [18,35]. For p(NIPAM), the particles deswell when the temperature exceeds the VPTT (35°C), thus at 45°C, they acquire a de-swollen configuration and the dispersion is more turbid.…”

“…It has two excitation wavelengths (430 and 280 nm) and emission wavelength at 540 nm [17]. Lucifer yellow is used for different biomedical applications including marking cells, neurons, albumin, cholesterol, phospholipids, collagenase, polynucleotides, progesterone derivatives, testosterone, estriol [16], and tracers of cell-cell fusion [18]. It is also selectively binds to copper [19] which can be used in industrial and environmental applications.…”