What is ANS fluorescence?
8-anilino-1-naphthalenesulfonic acid (ANS) is an extensively utilized fluorescent probe for the characterization of protein binding sites. ANS is often considered a non-fluorescence probe when bound to the exposed binding sites of proteins.
What is ANS dye?
The extrinsic fluorescence dye 8-anilino-1-naphthalene sulfonate (ANS) is widely used for probing conformational changes in pro- teins, yet no detailed structure of ANS bound to any protein has been reported so far.
What is intrinsic and extrinsic fluorescence?
An intrinsic fluorophore is a ion, molecule or macromolecule that fluoresces strongly in it native form while an extrinsic fluorophore is a species that has been made to fluoresce strongly through reaction with a fluorometric reagent. Among organic molecules only a small fraction are intrinsic fluorophores.
What is ANS chemistry?
8-Anilinonaphthalene-1-sulfonic acid (ANS), also called 1-anilino-8-naphthalenesulfonate, is an organic compound containing both a sulfonic acid and an amine group. This compound is used as a fluorescent molecular probe.
What do you mean by extrinsic fluorescence?
Extrinsic fluorophores are synthetic dyes or modified biochemicals that are added to a specimen to produce fluorescence with specific spectral properties. Absorption, Excitation, and Emission.
What is extrinsic fluorophore?
Extrinsic fluorophores are molecules labelled with a fluorescent dye (as opposed to intrinsic fluorescence or autofluorescence of molecules which does not require such labelling).
Why primary standard substances are used to make standard solutions?
Primary standards are typically used in titration to determine an unknown concentration and in other analytical chemistry techniques. The reaction confirms that the solution is at a specific concentration. Primary standards are often used to make standard solutions, solutions with a precisely known concentration.
What is the difference between extrinsic and intrinsic fluorescence?
Intrinsic fluorophores are those that occur naturally. Extrinsic fluorophores are added to the sample to provide fluorescence when none exists, or to change the spectral properties of the sample. Extrinsic fluorophores include dansyl, fluorescein, rho-damine, and numerous other substances.
Is tryptophan a fluorophore?
Tryptophan, which is the dominant intrinsic fluorophore, is generally present at about 1 mole% in proteins. The small number of tryptophan residues is probably the result of the metabolic expense of its synthesis.
What is naphthalene soluble?
A white, waxy solid, naphthalene is soluble in ether and hot alcohol and is highly volatile. It is used in mothballs, dyes and synthetic resins, and in the high-temperature cracking process of petroleum.
What is an1-anilino-8-naphthalene sulfonate anion?
1-Anilino-8-naphthalene sulfonate (ANS) anion is conventionally considered to bind to preexisting hydrophobic (nonpolar) surfaces of proteins, primarily through its nonpolar anilino-naphthalene group. Such binding is followed by an increase in ANS fluorescence intensity, similar to that occurring wh …
Is 1-anilinonaphthalene-8-sulfonic acid solvatochromic?
One of the first solvatochromic dyes, which still remains an essential tool for protein and membrane studies, is 1-Anilinonaphthalene-8-Sulfonic Acid (1,8-ANS). 13,27 In addition to the strong solvent-dependent shift in its emission spectrum, it shows a dramatic increase in fluorescence intensity on binding to biomolecules.
What is the fluorescence peak of 8-anilino-1-naphthalenesulfonic acid ammonium?
Upon binding to transport proteins, e.g. TTR, the fluorescence peak of 8-anilino-1-naphthalenesulfonic acid ammonium (ANSA) shifts from 515 to 465 nm and the fluorescence intensity is substantially increased.