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The peak of fluorescence occurs best with ultraviolet light, but violet/blue violet also gives great results of fluorescence. Calcofluor-White is an fluorescent dye, meaning it has an excitation and emission wavelength that differs from one another. The excitation wavelength is 380 nm while the emission is 475 nm.
Laundry detergent fluorescing under ultraviolet light. Optical brighteners, optical brightening agents (OBAs), fluorescent brightening agents (FBAs), or fluorescent whitening agents (FWAs), are chemical compounds that absorb light in the ultraviolet and violet region (usually 340-370 nm) of the electromagnetic spectrum, and re-emit light in the blue region (typically 420-470 nm) through the ...
The fluorescence of this molecule is very intense; peak excitation occurs at 495 nm and peak emission at 520 nm. Values for the deprotonated form in basic solution. [citation needed] Fluorescein has a pK a of 6.4, [2] and its ionization equilibrium leads to pH-dependent absorption and emission over the range of 5 to 9. Also, the fluorescence ...
NBD-TMA has an excitation maximum at 458 nm and an emission maximum at 530 nm. It also has a smaller local excitation maximum around 343 nm. The molar extinction coefficient is about 13,000 cm −1 M −1 and its overall effective fluorescence is about 1% that of fluorescein. It is only mildly sensitive to halide ion collision quenching.
Fluorescence in the life sciences is used generally as a non-destructive way of tracking or analysis of biological molecules by means of the fluorescent emission at a specific frequency where there is no background from the excitation light, as relatively few cellular components are naturally fluorescent (called intrinsic or autofluorescence).
When measuring fluorescence spectra, the wavelength of the excitation light is kept constant, preferably at a wavelength of high absorption, and the emission monochromator scans the spectrum. For measuring excitation spectra, the wavelength passing through the emission filter or monochromator is kept constant and the excitation monochromator is ...
Pyranine is a hydrophilic, pH-sensitive fluorescent dye from the group of chemicals known as arylsulfonates. [2] [3] Pyranine is soluble in water and is used as a coloring agent, biological stain, optical detecting reagent, and pH indicator.
The ultraviolet activity of umbelliferone led to its use as a sunscreen agent, and an optical brightener for textiles. It has also been used as a gain medium for dye lasers. Umbelliferone can be used as a fluorescence indicator for metal ions such as copper and calcium. It acts as a pH indicator in the range 6.5-8.9. [citation needed]