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4-formyl-benzamido-dPEG®₁₂-EDA-MAL (QBD-10075)



4-formyl-benzamido-dPEG®12-EDA-MAL, product number QBD-10075, is a medium-length (57 atoms, 59.6 Å) single molecular weight, discrete PEG (dPEG®) spacer functionalized with an aryl aldehyde on one end and a malemide reactive group on the other. It is designed for the stable crosslinking of biomolecules. The benzaldehyde group forms hydrazone bonds with hydrazine and hydrazide groups and oxime bonds with aldehydes and ketones, while the maleimide reactive group forms thioether bonds with free sulfhydryl groups.

Hydrazone bonds are acid-labile, allowing for constructs that self-disassemble in lysosomes, while oxime bonds are much more stable. The maleimide group allows for conjugation to free thiols on proteins and peptides. The single molecular weight dPEG® linker has no dispersity, which simplifies analytical considerations compared to polymer PEGs where the broad range of PEG chain lengths and molecular weights complicate the analysis of the conjugates.

The potential uses for this molecule include supramolecular construction of drug delivery systems and imaging applications.


Unit Size 100 mg, 1000 mg
Molecular Weight 943.04; single compound
Chemical formula C₄₄H₇₀N₄O₁₈
Purity > 98%
Spacers dPEG® Spacer is 57 atoms and 59.6 Å
Shipping Ambient
Typical solubility properties (for additional information contact Customer Support) Methylene Chloride, Acetonitrile, DMSO or Methanol.
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.

Applicable patents and legal notices are available at legal notices.

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