Azido-dPEG®₈-NHS ester

Azido-dPEG®8-NHS ester, product number QBD-10503, is a water-soluble click chemistry crosslinker containing an azide group linked to an N-hydroxysuccinimidyl (NHS) ester through a single molecular weight, discrete polyethylene glycol (dPEG®) spacer. Azido-dPEG®8-NHS ester works with copper(I)-catalyzed, ruthenium-catalyzed and with copper-free (e.g., strain-promoted) click chemistry. The dPEG® spacer imparts water solubility and adds hydrodynamic volume to the conjugated product. The single molecular weight product design, with its discrete chain length, simplifies the analysis of this product.

Our single molecular weight, discrete chain length PEG (dPEG®) products are a superior alternative to traditional polyethylene glycol products. Conventional PEGylation reagents consist of a complex mixture of different chain lengths due to the polymerization processes that form them. In contrast, each dPEG® product contains a discrete chain length of PEG with only one molecular weight. Conjugates made with dPEG® products have less complicated analyses compared to conjugates prepared with traditional PEGylation reagents.

NHS esters are the most popular, most widely used way to conjugate carboxylic acids to primary or secondary amines resulting in stable amide bonds. NHS esters react quickly and efficiently in aqueous media at physiological pH values (7.0 – 7.5). However, they are prone to hydrolysis at a rate that is pH-dependent. Published research shows that 2,3,5,6-tetrafluorophenyl (TFP) esters are more hydrolytically stable and have better reactivity with amines than NHS esters.