NHS ester-PEG7-COOH, Of NHS ester PEG Is For Targeted Drug Delivery

NHS ester-PEG7-COOH​ Of NHS ester PEG Is Applied In Bioconjugation

Description:

• NHS ester-PEG7-COOH is an amino (-NH₂) reactive PEG derivative that can be used to modify protein, peptide or any other surfaces with their available amino groups. NHS esters react with primary amine groups at pH 7~8.5 to form stable amide bonds.Compared to other PEG NHS ester derivatives, our succinimidyl carbonate (SC) functionalized mPEG-NHS offers superior reactivity and higher stability in aqueous solution. NHS esters react with deprotonated primary amines, therefore, the reaction requires neutral to basic pH values to proceed. Primary amines react with NHS esters by nucleophilic attack and NHS is released as a byproduct. Hydrolysis of the NHS-ester competes with the reaction in aqueous solution and increases with increasing pH.
• Succinimidyl esters are proven to be the best reagents for amine modifications because the amide bonds that are formed are essentially identical to, and as stable as peptide bonds. These reagents are generally stable if they are properly stored, and show good reactivity and selectivity with aliphatic amines. They have very low reactivity with aromatic amines, alcohols, phenols (including tyrosine) and histidine. Some succinimidyl esters have poor water solubility, and may not be readily used with a specific application. To overcome this limitation, sulfosuccinimidyl esters (SSE) can generally be prepared in situ from the corresponding carboxylic acids simply by dissolving the carboxylic acid dyes in a buffer that contains N-hydroxysulfosuccinimide (NHSS) and 1- ethyl-3-(3 dimethylaminopropyl)carbo-diimide (EDC). Addition of NHSS to the buffer has been shown to enhance the yield of carbodiimide-mediated conjugations.7 It was found that some N-hydroxysuccinimide (NHS) uronium salts can also be used to convert carboxylic acids to the corresponding succinimidyl esters in situ for conjugation reactions. The carboxylic acid derivatives may also be useful for preparing acid chlorides and anhydrides, which, unlike succinimidyl esters, can be used to modify aromatic amines and alcohols​

Physical Properties:

• Transparent and oil free liquid 
• Soluble in regular aqeous solution as well as most organic solvents;

Storage Conditions:

• Store at -20 ⁰C, desiccate. NHS PEG tends to hydrolyze from moisture. Avoid frequent thaw and frozen.