How does FITC labeling work?
Fluorescein isothiocyanate (FITC) is widely used to attach a fluorescent label to proteins vi a the amine group. The isothiocyanate group reacts with amino terminal and primary amines in proteins. It has been used for the labeling of proteins including antibodies and lectins.
What are NHS esters?
NHS esters are reactive groups formed by carbodiimide-activation of carboxylate molecules (see Carbodiimide Crosslinker Chemistry). NHS ester-activated crosslinkers and labeling compounds react with primary amines in physiologic to slightly alkaline conditions (pH 7.2 to 9) to yield stable amide bonds.
What is a primary amine?
Primary amine (1o amine): An amine in which the amino group is directly bonded to one carbon of any hybridization which cannot be a carbonyl group carbon. General primary amine molecular structure. X = any atom but carbon; usually hydrogen.
How do you make isothiocyanate?
Isothiocyanates are generally prepared by the reaction of a primary amine (e.g. aniline) and carbon disulfide in aqueous ammonia. This combination results in precipitation of the solid ammonium dithiocarbamate salt, which is then treated with lead nitrate to yield the corresponding isothiocyanate.
What is primary and secondary amine?
Amines are classified according to the number of carbon atoms bonded directly to the nitrogen atom. A primary (1°) amine has one alkyl (or aryl) group on the nitrogen atom, a secondary (2°) amine has two, and a tertiary (3°) amine has three (Figure 15.10. 1).
What is a secondary amine?
Secondary amine (2o amine): An amine in which the amino group is directly bonded to two carbons of any hybridization; these carbons cannot be carbonyl group carbons. General secondary amine structure. X = any atom but carbon; usually hydrogen.
What is the medical definition of isothiocyanate?
Medical Definition of isothiocyanate. : a compound containing the monovalent group −NCS : a salt or ester of isothiocyanic acid — see allyl isothiocyanate.
How do you make isothiocyanates from amines?
The general method for the formation of isothiocyanates proceeds through the reaction between a primary amine (e.g. aniline) and carbon disulfide in aqueous ammonia. This results in precipitation of the ammonium dithiocarbamate salt, which is then treated with lead nitrate to yield the corresponding isothiocyanate.
What is phenyl isothiocyanate?
An artificial isothiocyanate, phenyl isothiocyanate, is used for amino acid sequencing in the Edman degradation. Cruciferous vegetables, such as bok choy, broccoli, cabbage, cauliflower, kale, and others, are rich sources of glucosinolate precursors of isothiocyanates.
What is the reaction of isothiocyanate with thiols?
The reaction of isothiocyanate with thiols is a reversible reaction and the equilibrium shown in Fig. 6.2 is maintained. They also react with amino acids and amine groups to form other products (see Scheme 6.1 ). Scheme 6.1. Reactions of isothiocyanates.
