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m-dPEG®₄-MAL (QBD-10745)



m-dPEG®4-MAL, product number QBD-10745, is a thiol-reactive, single molecular weight, monodisperse PEG reagent that forms thioethers with sulfhydryls. The terminal maleimido group reacts rapidly and specifically at pH 6.5 – 7.5 with free thiols in a click chemistry type of reaction. The non-immunogenic dPEG® product increases the water solubility and hydrodynamic volume of conjugates made with it. Moreover, this product reduces or eliminates immunogenicity and non-specific interactions caused by hydrophobicity. This product is designed to modify small molecules, biomolecules, hydrogels, and surfaces (metal, glass, silica) containing free sulfhydryl groups.


Unit Size100mg, 1000mg
Molecular Weight358.39; single compound
Chemical formulaC₁₆H₂₆N₂O₇
Purity> 98%
SpacersdPEG® Spacer is 20 atoms and 22.1 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, 2nd Edition, Elsevier Inc., Burlington, MA 01803, April, 2008 (ISBN-13: 978-0-12-370501-3; ISBN-10: 0-12-370501-0). See all of the extensive references to the reactions of maleimides with a variety of compounds and applications, Hermanson, p. 1174 (index for maleimides) and references therein.

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.

Applicable patents and legal notices are available at legal notices.

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