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MAL-dPEG®₄-(m-dPEG®₁₂)₃ (QBD-10406)



MAL-dPEG®4-(m-dPEG®12)3, QBD-10406, is a thiol-reactive, branched, monodisperse PEG product that can modify the performance and distribution of biologic drugs. This single molecular weight, discrete-length PEG (dPEG®) product consists of a tris core from which branch three methyl-terminated dPEG®12 arms and one maleimide-functionalized dPEG®4 arm. From the reactive site on the maleimido group to the terminal methyl moiety on each of the dPEG®12 branches, the dPEG® spacer is 67 atoms (75.8 Å). This unique branched dPEG® construct increases the water solubility and hydrodynamic volume of conjugates that incorporate it. Also, MAL-dPEG®4-(m-dPEG®12)3 can reduce or eliminate immunogenicity and non-specific, hydrophobic interactions.

MAL-dPEG®4-(m-dPEG®12)3 is best used to modify proteins, peptides, and other large biomolecules. Maleimide reacts with free thiols that occur in such molecules. The thiol-maleimide reaction is rapid and specific within the optimal pH range (6.5 – 7.5).
Scientific publications report using MAL-dPEG®4-(m-dPEG®12)3 several times. These uses include probing protein structure and function, PEGylating cell surfaces, and dissecting protein-protein interactions. The reference work Bioconjugate Techniques, 3rd edition, by Greg T. Hermanson, contains specific protocols for the maleimide-thiol reaction.


Unit Size100 mg, 1000 mg
Molecular Weight2360.75
Chemical formulaC₁₀₆H₂₀₂N₆O₅₀
Purity> 96%
SpacersdPEG® Spacer is 67 atoms and 75.8 Å, Avg.
Typical solubility properties (for additional information contact Customer Support)Methylene chloride, DMAC, DMSO, water or Acetonitrile.
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). Chapter 1, p. 30.

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.

Enzymatic Deglutathionylation to Generate Interleukin-4 Cysteine Muteins with Free Thiol. Viswanadham Duppatla, Maja Gjorgjevikj, Werner Schmitz, Mathias Kottmair, Thomas D. Mueller, and Walter Sebald. Bioconjugate Chem., 2012, 23 (7), pp 1396–1405 June 9, 2012. DOI: 10.1021/bc2004389.

Inactivation by oxidation and recruitment into stress granules of hOGG1 but not APE1 in human cells exposed to sub-lethal concentrations of cadmium. Anne Bravard, Anna Campalans, Monique Vacher, Barbara Gouget, Céline Levalois, Sylvie Chevillard, J. Pablo Radicella. Mutation Research. 2010, 685 (1-2) pp 61-69. October 2, 2009. DOI: 10.1016/j.mrfmmm.2009.09.013.

Surface Location of Individual Residues of SlpA Provides Insight into the Lactobacillus brevis S-Layer. Heikki Vilen, Ulla Hynönen, Helga Badelt-Lichtblau, Nicola Ilk, Pentti Jääskeläinen, Mika Torkkeli and Airi Palva. J. Bacteriol. 2009, 191 (10) pp 3339-3351. March 20, 2009. DOI: 10.1128/JB.01782-08.

Dissecting Molecular Interactions Involved in Recognition of Target Disulfides by the Barley Thioredoxin System. Olof Bjornberg, Kenji Maeda, Birte Svensson, and Per Hagglund. Biochemistry. 2012, 51 (49) pp 9930-9939. November 19, 2012. DOI: 10.1021/bi301051b.

The Chloroplast Twin Arginine Transport (Tat) Component, Tha4, Undergoes Conformational Changes Leading to Tat Protein Transport. Cassie Aldridge, Amanda Storm, Kenneth Cline and Carole Dabney-Smith. J. Biol. Chem. 2012, 287 (1) pp 34752-34763. August 15, 2012. DOI: 10.1074/jbc.M112.385666.

Inhibition of fatty acid oxidation enhances oxidative protein folding and protects hepatocytes from endoplasmic reticulum stress. Heather M. Tyra, Douglas R. Spitz, and D. Thomas Rutkowski. Molecular Biology of the Cell. 2012, 23 (5) pp 811-819. March 1, 2012. DOI: 10.1091/mbc.E11-12-1011.

Oxidation Status of Human OGG1-S326C Polymorphic Variant Determines Cellular DNA Repair Capacity. Anne Bravard, Monique Vacher, Eva Moritz,Laurence Vaslin, Janet Hall,Bernd Epe,and J. Pablo Radicella. Cancer Research.2009, 69 (8) pp 3642-3649.April 7, 2009. DOI: 10.1158/0008-5472.CAN-08-3943.

Tau protein assembles into isoform- and disulfide-dependent polymorphic fibrils with distinct structural properties. Furukawa Y, Kaneko K, Nukina N. . The Journal of Biological Chemistry. 2011, 286 (31) pp 27236-46. June 9, 2011. DOI: 10.1074/jbc.M111.248963.

Type IV Pilus Secretins Have Extracellular C Termini. Joshua A. Lieberman, Courtney D. Petro, Stefani Thomas, Austin Yang and Michael S. Donnenberga. mBio. 2015, 6(2) pp 1-13. March 24, 2015. DOI: 10.1128/mBio.00322-15.

The Regulatory Domain of Squalene Monooxygenase Contains a Re-entrant Loop and Senses Cholesterol via a Conformational Change. Vicky Howe, Ngee Kiat Chua, Julian Stevenson, and Andrew J. Brown. The Journal of Biological Chemistry. 2015, 290 (42). October 3, 2015. DOI: 10.1074/jbc.M115.675181.

Development of Raman Spectroscopy as a clinical Diagnostic Tool. Santa Borel. Tspace. 2016, pp 1-99. November 2016.

Applicable patents and legal notices are available at legal notices.

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