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Hydroxy-dPEG®₈-t-butyl ester (QBD-10185)



Hydroxy-dPEG®8-t-butyl ester, product number QBD-10185, is a versatile discrete PEG building block based upon a monodispersed polyethylene glycol (PEG) chain. A primary alcohol group terminates one end of the molecule. The opposite end is a propionic acid group protected as the tert-butyl ester. The terminal hydroxy group can be functionalized with various reactive groups to permit direct modification of surfaces, small molecules, or biomolecules.

Alternatively, the hydroxy group can react with isothiocyanates or active esters of carboxylic acids to form new conjugates. The tert-butyl ester deprotects with trifluoroacetic acid (TFA) or formic acid, exposing the terminal propionic acid, which can then be activated as the NHS or TFP ester or directly coupled to an amine using a suitable carbodiimide.


Unit Size100 mg, 1000 mg
Molecular Weight498.60; single compound
Chemical formulaC₂₃H₄₆O₁₁
Purity> 98%
SpacersdPEG® Spacer is 28 atoms and 32.1 Å
Typical solubility properties (for additional information contact Customer Support)Methylene chloride, Acetontrile, 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.


  1. 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.
  2. How a grafting anchor tailors cellular uptake and in vivo fate of dendronized iron oxide nanoparticles. C. Bordeianu, A. Parat, C. Affolter-Zbaraszczuk, R. N. Muller, S. Boutry, S. Begin-Colin, F. Meyer, S. Laurent, and D. Felder-Flesch. Journal of Materials Chemistry B. 2017, 2013 (00) pp 1-3. May 26, 2017. DOI: 10.1039/C7TB00781G.

Applicable patents and legal notices are available at legal notices.

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