What is self-quenching in fluorescence?
Self-quenching is a special type of fluorescence quenching in which fluorophore and quencher molecules are the same. Fluorescence self-quenching is particularly evident in highly concentrated solutions of fluorophores at right-angle geometry [15], [18], [19].
What causes self-quenching fluorescence?
Self-quenching can occur via various mechanisms such as collisions between excited fluorophores, the formation of non-fluorescent dimers, and energy transfer to the nonfluorescent dimers [6–11].
What do you mean by self-quenching?
Self-quenching (also called cross-relaxation) occurs between two identical molecules (ions) when a first molecule (or ion) initially in an excited state exchanges energy with the second molecule (ion) that is initially in the ground state, resulting in both molecules (ions) simultaneously changing to excited states …
What is fluorescence quenching used for?
Fluorescence quenching is an important technique for measuring binding affinity between ligands and proteins. Fluorescence quenching is the decrease in the quantum yield of fluorescence from a fluorophore, induced by a variety of molecular interactions with quencher molecule(s).
What is self quenching in GM counter?
Self-quenching or internal-quenching tubes stop the discharge without external assistance, originally by means of the addition of a small amount of a polyatomic organic vapor originally such as butane or ethanol, but for modern tubes is a halogen such as bromine or chlorine.
What is fluorescence quenching Slideshare?
Quenching of fluorescence Quenching refers to any process that reduces the fluorescence intensity of a given substance. This may occur due to various factors like pH, concentration, temperature, viscosity, presence of oxygen, heavy metals or, specific chemical substances etc.
What is quenching and tempering process?
Quenching and tempering are processes that strengthen materials like steel and other iron-based alloys. These processes strengthen the alloys through heating the material while simultaneously cooling in water, oil, forced air, or gases such as nitrogen.
What does quenching mean in chemistry?
Quenching refers to any process which decreases the fluorescence intensity of a given substance. A variety of processes can result in quenching, such as excited state reactions, energy transfer, complex-formation and collisional quenching. Molecular oxygen, iodide ions and acrylamide are common chemical quenchers.
Why tungsten wire is used in GM counter?
Tungsten has a high atomic number and a high density, both of which give the metal unusually good absorption cross-section. This makes the metal very sensitive to gamma rays.
