What is self-quenching 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].
Why does self-quenching occur?
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 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 aggregation caused quenching?
Aggregation-caused quenching (ACQ) is a known phenomenon responsible for low emission of dyes when in the form of solid state (e.g. in nanostructures, nano-precipitates), although in solution (in appropriate solvent) these are characterized with bright emission [27,28].
How is self quenching eliminated?
We found that most of the self-quenching can be partially eliminated by proximity of the labeled protein to metallic silver particles. These results suggest the use of heavily labeled proteins and metallic colloids to obtain ultrabright reagents for use in immunoassays, imaging, and other applications.
What is static fluorescence quenching?
Static quenching (or contact quenching) of fluorescence is, when a Fluorphor (F) and a Quencher (Q) are creating a NON-FLUORESCENT complex (FQ) BEFORE EXCITATION OF F. The chemical equation therefore is: F + Q ⇌ FQ.
What are the types of quenching?
There are ten quenching methods in the heat treatment process, which are:
- single-medium (water, oil, air) quenching;
- interrupted quenching;
- martempering;
- martempering below MS point;
- isothermal quenching of bainite;
- compound quenching;
- precooled isothermal quenching;
- delayed cooling quenching;
How is GM quenching obtained?
To counter this, the noble gas is in general mixed with halogen or alcohol. Now the excited halogen or alcohol molecules dissociate at cathode being neutralized by capture of electrons. This process is known as Quenching or Self Quenching or Internal Quenching.
What is concentration quenching?
If the concentration of an activator is higher than an appropriate value (typically several mol%), the emission intensity of the phosphor mostly will be decreased. This is called concentration quenching. The origin of this phenomenon is due to energy transfer between activator ions [7].
