m-dPEG®₁₂-NHS ester

m-dPEG®12-NHS ester, product number 10262, is a medium length, methyl-terminated, discrete length polyethylene glycol (dPEG®) spacer. With a reactive end as the N-hydroxysuccinimidyl (NHS) ester, m-dPEG®12-NHS ester is designed to modify surfaces containing accessible free amines. Except for the reactive ester, this product is essentially identical to m-dPEG®12-TFP ester, product number 10306.

NHS reacts optimally with free amines at pH 7.2 – 7.5. In aqueous media, the hydrolytic rate of the ester to the carboxylic acid increases with increasing pH. Reacting surface amines on biomolecules (e.g., proteins and peptides) with this uncharged, methyl-capped dPEG® spacer may alter the overall charge of the resulting conjugates.

Many applications employ this m-dPEG®12-NHS ester. Published papers using this product include uses in:

vaccine development;
cell surface engineering;
multimodal imaging;
stable antimicrobial, cytotoxic dendrimers;
nanoparticles for siRNA delivery;
coating of nanoparticles, quantum dots, and carbon nanotubes;
PK and immunogenicity improvements for organophosphorus hydrolase;
PK and immunogenicity improvements for poly-L-lysine dendrimers used as drug delivery vehicles to tumors; and,
preventing enzyme aggregation.

m-dPEG®12-NHS ester, product number 10262, is just one member of an comprehensive line of methyl-terminated dPEG® products. This line includes dPEG® spacers containing 2 to 49 ethylene glycol units. These products are functionalized with NHS or with 2,3,5,6-tetrafluorophenol (TFP). TFP has proven to be superior to NHS for amine-reactive products.

Quanta BioDesign, Ltd., makes and sells single molecular weight PEG linkers and spacers with discrete chain lengths under the trade name dPEG®. Our products are distinctly different from traditional PEG products in that they are not disperse polymers. However, they confer all of the benefits of traditional PEG products.

Please contact us at for specific academic pricing.