China maleic anhydride manufacturers


Talking About N-Hydroxy Succinimide

N-Hydroxy succinimide functions by stabilizing the protein-EDC intermediate, thus allowing for a more efficient crosslinking reaction.N-Hydroxy Succinimide is a white powder or colorless crystal, easily soluble in many kinds of solvents, resolved in succinic acid and ammonia with water.N-Hydroxysuccinimide (NHS) is used as a catalyst in the zero-length crosslinking of proteins with EDC.
N-hydroxysuccinimide (NHS) esters have been used for gas-phase conjugation reactions with peptides at nucleophilic sites, such as primary aminesor guanidines, by forming amide bonds through a nucleophilic attack on the carbonyl carbon. The carboxylate has recently been found to also be a reactive nucleophile capable of initiating a similar nucleophilic attack to form a labile anhydride bond. The fragile bond is easily cleaved, resulting in an oxygen transfer from the carboxylate-containing species to the reagent, nominally observed as a water transfer. This reactivity is shown for both peptides and non-peptidic species.
Reagents isotopically labeled with O18 were used to confirm reactivity. This constitutes an example of distinct differences in reactivity of carboxylates between the gas phase, where they are shown to be reactive, and the solution phase, where they are not regarded as reactive with NHS esters.