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m-dPEG®₂₄-MAL (QBD-10319)



m-dPEG®24-MAL, product number QBD-10319, is a sulfhydryl-reactive, single molecular weight, with a discrete chain length PEG (dPEG®). This product modifies surfaces and biomolecules with free thiol groups through the maleimide reactive group. The non-immunogenic, methyl-terminated dPEG® chain has no charge but adds water solubility and hydrodynamic volume to molecules to which it is conjugated.

The reaction of the maleimide end of m-dPEG®24-MAL, product number QBD-10319, with a sulfhydryl proceeds best at pH 6.5 – 7.5. Conduct the conjugation at the lowest reasonable pH within this range. Above pH 7.5, free amines compete with free thiols at the maleimide reaction site, which creates confusing results. Moreover, at higher pH values, the maleimide ring may open to form unreactive maleamic acid.
Published uses for m-dPEG®24-MAL include the following:
modifying surface-accessible free thiols on enzymes to probe enzymatic function;
developing a virus-based drug delivery system; and,
developing probes of cellular redox reactions.


Unit Size100 mg, 1000 mg
Molecular Weight1239.44; single compound
Chemical formulaC₅₆H₁₀₆N₂O₂₇
Purity> 98%
SpacersdPEG® Spacer is 80 atoms and 50.7 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). Specifically see pp. 726-729 in his Chapter 18 on discrete PEG compounds for pegylation applications.

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.

Modulation of Cell Surface Protein Free Thiols: A Potential Novel Mechanism of Action of the Sesquiterpene Lactone Parthenolide. Jolanta Skalska, Paul S. Brookes, Sergiy M. Nadtochiy, Shannon P. Hilchey, Craig T. Jordan, Monica L. Guzman, Sanjay B. Maggirwar, Margaret M. Briehl, Steven H. Bernstein. PLoS ONE. 4 (12), e8115. December 2, 2009. DOI: 10.1371 /journal.pone.0008115.

Cell-Specific Delivery of Diverse Cargos by BacteriophageMS2 Virus-like Particles. Carlee E. Ashley Eric C. Carnes, Genevieve K. Phillips, Paul N. Durfee, Mekensey D. Buley, Christopher A. Lino, David P. Padilla, Brandy Phillips, Mark B. Carter, Cheryl L. Willman, C. Jeffrey Brinker, Jerri do Carmo Caldeira, Bryce Chackerian, Walker Wharton, and David S. Peabody.ACS Nano, 2011, 5 (7), pp 5729–5745, May 26, 2011. DOI: 10.1021/nn201397z.

Going through the barrier: coupled disulfide exchange reactions promote efficient catalysis in Quiescin sulfhydryl oxidase. Benjamin A. Israel, Vamsi K. Kodali, and Colin Thorpe. The Journal of Biological Chemistry. 2013, December 30, 2013. DOI: 10.1074/jbc.M113.536219.

2-Cys peroxiredoxins participate in the oxidation of chloroplast enzymes in the dark. Valle Ojeda, Juan Manuel, Pérez-Ruiz, and Francisco Javier Cejudo. Molecular Plant. 2018, pp 1-32. October 4, 2018. DOI: 10.1016/j.molp.2018.09.005.

Complement Activation and Cell Uptake Responses Toward Polymer-Functionalized Protein Nanocapsules. Nicholas M. Molino, Kateryna Bilotkach, Deborah A. Fraser, Dongmei Ren, and Szu-Wen Wang. Biomacromolecules, 2012, 13 (4), pp 974–981. March 14, 2012. DOI: 10.1021/bm300083e.

Redox-regulated dynamic interplay between Cox19 and the copper-binding protein Cox11 in the intermembrane space of mitochondria facilitates biogenesis of cytochrome c oxidase. Manuela Bode, Michael W. Woellhaf, Maria Bohnert, Martin van der Laan, Frederik Sommer, Martin Jung, Richard Zimmermann, Michael Schroda, Johannes M. Herrmann. Molecular Biology of the Cell. April 29, 2015. DOI: 10.1091/mbc.E14-11-1526

NTRC-dependent redox balance of 2-Cys peroxiredoxins is needed for optimal function of the photosynthetic apparatus. Juan Manuel Pérez-Ruiz, Belén Naranjo, Valle Ojeda, Manuel Guinea, and Francisco Javier Cejudo. Proceedings of the National Academy of Sciences of the United States of America. 2017, 114 (45) pp 12069-12074. 9/26/2017. DOI: 10.1073/pnas.1706003114.

A chloroplast redox relay adapts plastid metabolism to light and affects cytosolic protein quality control. Valle Ojeda, Julia Jiménez-López, Francisco José Romero-Campero, Francisco Javier Cejudo, Juan Manuel Pérez-Ruiz. Plant Physiology. 2021, kiab246. 05/26/2021. DOI: 10.1093/plphys/kiab246

Protocol for determining protein cysteine thiol redox status using western blot analysis, Bikram Datt Pant, Sunhee Oh, Hee-Kyung Lee, Raja Sekhar Nandety, Kirankumar S. Mysore, Volume 33, Issue 11, 15 December 2020,

Aim32 is a dual-localized 2Fe-2S mitochondrial protein that functions in redox quality control, Danyun Zhang, Owen R. Dailey, Daniel J. Simon, James A. Wohlschlegel, Carla M. Koehler, Deepa V. Dabir, Journal of Biological Chemistry, 2021, Volume 297, Issue 4, 10/2021, DOI: 10.1016/j.jbc.2021.101135

Depletion of m-type thioredoxin impairs photosynthesis, carbon fixation, and oxidative stress in cyanobacteria. Manuel J Mallén-Ponce, María José Huertas, Ana María Sánchez-Riego, Francisco J Florencio. Plant Physiology. 2021. Volume 187, Issue 3. July 15, 2021. DOI: 10.1093/plphys/kiab321

Characterization of the Gluathione-dependent reduction of the perixiredoxin 5 homolog PfAOP from Plasmodium Falciparum. Robin Chumann, Lukas Lang, Marcel Deponte. Wiley Online Library. 2022. Volume 31, Issue 5. April 9, 2022.

Regulation of Derlin-1-mediated degradation of NADPH oxidase partner p22phox by thiol modification. Kei Miyano, Shuichiro Okamoto, Mizuho Kajikawa, Takuya Kiyohara, Chikage Kawai, Akira Yamauchi, Futoshi Kuribayashi. Redox Biology, Volume 56, October 2022, 102479. 08/12/2022.

Applicable patents and legal notices are available at legal notices.

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