Fluorescence
| Also Known As | Photoluminescence, luminescence, fluorescent emission, Stokes shift phenomenon |
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What is Fluorescence?
Fluorescence is a type of photoluminescence in which a molecule absorbs light at one wavelength and re-emits light at a longer wavelength (lower energy) almost instantaneously (within nanoseconds). The difference between excitation and emission wavelengths is called the Stokes shift. Fluorescence ceases immediately when the excitation source is removed, distinguishing it from phosphorescence.
Properties & Characteristics
Uses & Applications
Safety Information
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
Key Facts
Frequently Asked Questions
Fluorescence is a type of photoluminescence in which a molecule absorbs light at one wavelength and re-emits light at a longer wavelength (lower energy) almost instantaneously (within nanoseconds). The difference between excitation and emission wavelengths is called the Stokes shift. Fluorescence ceases immediately when the excitation source is removed, distinguishing it from phosphorescence.
Fluorescent lighting and LEDs. Biological imaging and microscopy (fluorescent dyes, GFP). Medical diagnostics (immunofluorescence, flow cytometry). Chemical analysis (fluorimetry). Fluorescent whitening agents in detergents. Security features in currency and documents. Gemstone identification.
UV radiation used to excite fluorescence is hazardous to eyes and skin. Some fluorescent dyes are toxic or carcinogenic. Fluorescent compounds in laboratory settings should be handled with appropriate PPE. X-ray fluorescence involves ionizing radiation.