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Azido-dPEG®₈-NHS ester (QBD-10503)



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.


Unit Size100 mg, 1000 mg
Molecular Weight564.58; single compound
Chemical formulaC₂₃H₄₀N₄O₁₂
Purity> 98%
SpacersdPEG® Spacer is 28 atoms and 32.2 Å
Typical solubility properties (for additional information contact Customer Support)Methylene chloride, Acetonitrile, DMAC, or DMSO.
Storage and handling-20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.


Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.

A Modular Platform for the Rapid Site-Specific Radiolabeling of Proteins with F Exemplified by Quantitative Positron Emission Tomography of Human Epidermal Growth Factor Receptor 2. Herman S. Gill, Jeff N. Tinianow, Annie Pgasawara, Judith E. Flores, Alexander N. Vanderbilt, Helga Raab, Justin M. Scheer, Richard Vandlen, Simon-P. Williams, and Jan Marik, J. Med. Chem., 2009, 52 (19), pp 5816–5825 September 9, 2009. DOI: 10.1021/jm900420c.

An Effective Targeted Nanoglobular Manganese(II) Chelate Conjugate for Magnetic Resonance Molecular Imaging of Tumor Extracellular Matrix. Mingqian Tan, Xueming Wu, Eun-Kee Jeong, Qianjin Chen, Dennis L. Parker, and Zheng-Rong Lu,Mol. Pharmaceutics, 2010, 7 (4), pp 936–943 May 19, 2010. DOI: 10.1021/mp100054m.

Constant-speed vibrational signaling along polyethylene glycol chain up to 60-Å distance. Zhiwei Lin and Igor V. Rubtsov. PNAS, 2012, 5 (109), pp 1413-1418, January 31, 2012. DOI:10.1073/pnas.1116289109.

Ballistic energy transport along PEG chains: distance dependence of the transport efficiency. Zhiwei Lin , Nan Zhang , Janarthanan Jayawickramarajah and Igor V. Rubtsov. Physical Chemistry Chemical Physics. 2012, 30 (14), pp 10445-10454. April 12, 2012. DOI: 10.1039/C2CP40187H.

Enzymatic Ligation of Large Biomolecules to DNA. Rasmus Schøler Sørensen, Anders Hauge Okholm, David Schaffert, Anne Louise Bank Kodal, Kurt V. Gothelf, and Jørgen Kjems. ACS Nano. 2013, 7 (9) pp 8098–8104. August 8, 2013. DOI: 10.1021/nn403386f.

Click Chemistry Immobilization of Antibodies on Polymer Coated Gold Nanoparticles. Chiara Finetti, Laura Sola, Margherita Pezzullo, Davide Prosperi, Miriam Colombo, Benedetta Riva, Svetlana Avvakumova, Carlo Morasso, Silvia Picciolini, and Marcella Chiari. Langmuir. 2016, 32, pp 7435-7441. July 1, 2016. DOI: 10.1021/acs.langmuir.6b01142.

Modular Assembly of Cell-targeting Devices Based on an Uncommon G-quadruplex Aptamer. Felipe Opazo, Laura Eiden, Line Hansen, Falk Rohrbach, Jesper Wengel, Jørgen Kjems, and Günter Mayer. Molecular Therapy Nucleic Acids. 2015, 4 pp e251. 9/1/2015. DOI: 10.1038/mtna.2015.25.

Applicable patents and legal notices are available at legal notices.

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