Lucifer dyes

Stewart, W.W. (1981a) Lucifer dyes—Highly fluorescent dyes for biological tracing. Nature (London) 292, 17. 

Nontoxic but highly fluorescent dyes are used to study diffusion within and between cells. The so called Lucifer dyes have been employed to trace shapes and brandling patterns in neurons.175... 

Structural formula for Lucifer dyes For Lucifer yellow R = —NH—CO—NH—NH2... 

Lucifer Yellow probes are water-soluble to at least 1.5%. The absorbance maximum of the derivatives occurs at about 426—428 nm with an emission peak at about 530—535 nm, in the yellow region of the spectrum. The quantum yield of Lucifer dyes is about 0.25. The good intensity of luminosity from these dyes makes possible detection of small quantities of labeled molecules intracellularly. The fluorescent conjugates are readily visible in living cells at concentrations that are nontoxic to cell viability. The low molecular weight and water solubility of these dyes allow passage of labeled compounds from one cell to another, potentially revealing molecular relationships... 

In xanthenes, even if all one-photon allowed transitions are also two-photon allowed, the shape of the bands and their relative intensities are very different in the IPA and 2PA spectra [76,78]. This is not the case for other laser dyes and chromophores, for which the two spectra are almost identical (if represented as a function of the total transition energy), showing peaks in the same position and with very similar band shapes. Some example of chromophores in this category are coumarin 307 [78], coumarin 102 [80], 7-hydroxycoumarin [81], lucifer yellow [78], and cascade blue [78]. 

Fig. 4.4. Lucifer yellow carbohydrazide dye indicating water flow applied to a deep-root chamber, and detected in mycorrhizal hyphae in a hyphal chamber after crossing airgaps that restrict diffusion. Panel A is an AM hypha that transported the dye during the night (hydraulic lift). Panel B shows a mycorrhizal fungus hydrophilic tip, with hydraulically lifted water exuding out the tip onto a piece of organic detritus. Photographs by Louise Egerton-Warburton and details of the experiment can be found in Querejeta et al. (2003).

Usually, a 4-10% solution of Lucifer Yellow CH in lithium chloride is iontophoreticaUy injected through glass capillaries by passing current (1-3 nA) pulses (50-500 nsec) at 10 or 1 Hz, respectively (Miller and Goodenough, 1985 Schuetze and Good-enough, 1982). Transfer of the dye into the surrounding cells can be observed under a fluorescence microscope about 10 min after the injection. If required, cells can be fixed after dye injection by incubation for at least 20 min in 4% paraformaldehyde in PBS (Ren et al., 1990). 

Lil) of 0.05% of Lucifer Yellow CH and Rhodamine dextran (mw 10,000) in PBS at room temperature. The dish is swirled to distribute the solution evenly, and then cells in the culture are scraped off the dish with a cell scraper. Cells are immediately resuspended in complete culture medium, rinsed at least twice by centrifugation to remove unincorporated macromolecules, and replated on a new dish containing a culture of cells which are the potential recipients of the dye via gap junction formation. After 1 h of incubation at 37°C, the dish can be examined under an epifluorescence phase microscope at the appropriate wavelengths. 

A general synthesis of 3,6-disulphonated 4-aminonaphtl limides (108), the Lucifer Yellow dyes, is... 

Paternostro MA, Reyher CKH, Brunjes PC. 1995. Intracellular injections of Lucifer Yellow into lightly fixed mitral cells reveal neuronal dye-coupling in the developing rat olfactory bulb. Dev Brain Res 84 1-10. 

The affinity-purified connexin-32 was incorporated into unilamellar liposomes as before. The connexin-32 induced a sucrose permeability in liposomes, as assayed by the density-shift technique, and gave results essentially identical to those in Figure 2. Liposomes that were sucrose-permeable did not retain the dye Lucifer Yellow (retained by the sucrose-impermeable liposomes), which is near the upper size-permeability limit for gap junction channels (19, 108, 109). The fraction of the liposomes that were permeable to sucrose decreased by a factor of 4 when the pH in the gradients was changed from 7.5 to 6.0. This effect was partially reversible. 

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