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MAL-dPEG®₂-NHS ester (QBD-10266)



MAL-dPEG®2-NHS ester, product number QBD-10266, is a thiol-reactive and amine-reactive crosslinking reagent that joins a sulfhydryl to a free amine. The sulfhydryl groups react with a maleimide group via a Michael addition reaction. The amines form amide bonds with the crosslinker by nucleophilic substitution of the N-hydroxysuccinimidyl (NHS) ester of a carboxylic acid group. The maleimide and NHS functional groups on the crosslinking compound sit at either end of a short, discrete-length polyethylene glycol chain (dPEG®).

The reaction of the maleimide end of MAL-dPEG®2-NHS ester proceeds optimally at pH 7.0 – 7.5, though it can go as low as pH 6.5. Use the lowest reasonable pH within this range. Above pH 7.5, free amines compete with free thiols at the maleimide reaction site, causing confusing results. Moreover, at higher pH values, the maleimide ring may open to form unreactive maleamic acid.

The use of MAL-dPEG®2-NHS ester has been published in many different scientific papers and patents. The following list highlights some of the more notable uses of this product:
Cell targeting;
Crosslinking peptides to passivated nanoparticle surfaces;
Stem cell membrane engineering;
Biosensor development;
Cell capture using aptamers;
Controlled, targeted delivery of siRNA;
Development of extracellular antibody-drug conjugates; and,
Development of multiplex assays.


Unit Size100 mg, 1000 mg
Molecular Weight425.39; single compound
Chemical formulaC₁₈H₂₃N₃O₉
Purity> 98%
SpacersdPEG® Spacer is 16 atoms and 17.7 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); See pp. 276-335 for general description and use of heterobifunctional crosslinkers, as well as his specific discussion with protocols of our MAL-dPEG®x-NHS esters on pp. 718-722.

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.

Cell selective targeting of a simian virus 40 virus-like particle conjugated to epidermal growth factor. Yuichi Kitai, Hajime Fukuda, Teruya Enomoto, Yuki Asakawa, Takahiro Suzuki, Satoshi Inouye, Hiroshi Handa. Journal of Biotechnology. 2011, 155 (2) pp 251-256. Sept 10, 2011. DOI: 10.1016/j.jbiotec.2011.06.030.

Conjugation of Peptides to the Passivation Shell of Gold Nanoparticles for Targeting of Cell-Surface Receptors. Lisa Maus, Oliver Dick, Hilmar Bading, Joachim P. Spatz, and Roberto Fiammengo. ACS Nano. 2010, 4 (11), pp 6617–6628. October 12, 2010. DOI: 10.1021/nn101867w.

Stem cell membrane engineering for cell rolling using peptide conjugation and tuning of celleselectin interaction kinetics. Hao Cheng, Marta Byrska-Bishop, Cathy T. Zhang, Christian J. Kastrup, Nathaniel S. Hwang, Albert K. Tai, Won Woo Lee, Xiaoyang Xu, Matthias Nahrendorf , Robert Langer, Daniel G. Anderson. Biomaterials. 2012, 33 (20), pp 5004-5012. July 2012. DOI: 10.1016/j.biomaterials.2012.03.065.

Sensitive detection of small molecule–protein interactions on a metal-insulator-metal label-free biosensing platform. Amir Syahir, Kotaro Kajikawa and Hisakazu Mihara. Europe PubMed Central. 2012, 7 (8) pp 1867-1874. May 25, 2012. DOI: 10.1002/asia.201200138.

Aptamer-Containing Surfaces for Selective Capture of CD4 Expressing Cells. Qing Zhou, Ying Liu, Dong-Sik Shin, Jaime Silangcruz, Nazgul Tuleuova, and Alexander Revzin. Langmuir. 2012, 28 (34) pp 12544−12549. August 1, 2012. DOI: 10.1021/la2050338.

NIR light controlled photorelease of siRNA and its targeted intracellular delivery based on upconversion Nanoparticles. Yanmei Yang, Fang Liu, Xiaogang Liu and Bengang Xing. Nanoscale. 2013, 5 (1) pp 231-238. Oct 30, 2012. DOI: 10.1039/C2NR32835F.

Attachment of hydrogel microstructures and proteins to glass via thiol-terminated silanes. Jeong Hyun Seo, Dong-Sik Shin, Priam Mukundan, Alexander Revzin. Colloids and Surfaces B: Biointerfaces. 2012, 98 pp 1–6. October 1, 2012. DOI: org/10.1016/j.colsurfb.2012.03.025.

A sandwich-type DNA array platform for detection of GM targets in multiplex assay. Sena Cansız, Can Ozen, Ceren Bayrac, A. Tahir Bayrac, Fatma Gul, Murat Kavruk, Remziye Yılmaz, Fusun Eyidogan, Huseyin, Avni Oktem. European Food Research and Technology. 2012, 235 (3) pp 429-437. July 6, 2012. DOI: 10.1007/s00217-012-1767-y.

Extracellular Antibody Drug Conjugates Exploiting the Proximity of Two Proteins. David J Marshall, Scott S Harried, John L Murphy, Chad A Hall, Mohammed S Shekhani, Christophe Pain, Conner A Lyons, Antonella Chillemi, Fabio Malavsi, Homer L Pearce, Jon S Thorson, and James R Prudent. MT Open. 2016. July 19, 2016. DOI: 10.1038/mt.2016.119.

A simple DNA handle attachment method for single molecule mechanical manipulation experiments. Duyoung Min, Mark A. Arbing, Robert E. Jefferson, and James U. Bowie. Protein Science, 2016, 25 pp 1535-1544. May 24, 2016. DOI: 10.1002/pro.2952.

A virus-like particle vaccine platform elicits heightened and hastened local lung mucosal antibody production after a single dose. Laura E. Richert, Amy E. Servidb, Ann L. Harmsen, Agnieszka Rynda-Apple, Soo Han, James A. Wiley, Trevor Douglas, Allen G. Harmsen. Vaccine. 2012, 30 (24) pp 3653-3665. May 21, 2012. DOI: 10.1016/j.vaccine.2012.03.035.

The use of glass substrates with bi-functional silanes for designing micropatterned cell-secreted cytokine immunoassays. Seo JH, Chen Li, Verkhoturov SV, Schweikert EA, Revzin A. Biomaterials. 2011, 32 (23) pp 5478-5488. August 2011. DOI: 10.1016/j.biomaterials.2011.04.026.

Comparison between polyethylene glycol and zwitterionic polymers as antifouling coatings on wearable devices for selective antigen capture from biological tissue. Kye J. Robinson, Jacob W. Coffey, David A. Muller, Paul R. Young, Mark A. F. Kendall, Kristofer J. Thurecht, Lisbeth Grondahl, and Simon R. Corrie. Biointerphases. 2015, 10 (4) pp 04A305. December 2015. DOI: 10.1116/1.4932055.

A neutralized non-charged polyethylenimine-based system for efficient delivery of siRNA into heart without toxicity. Fang Wang, Lu Gao, Liu-Yi Meng, Jing-Ming Xie, Jing-Wei Xiong, and Ying Luo. ACS Applied Materials and Interfaces. 2016, pp 1-43. November 17, 2016. DOI: 10.1021/acsami.6b13295.

Drug-free albumin-triggered sensitization of cancer cells to anticancer drugs. LianLi, Jiyuan Yang, Sirima Soodvilaia, Jiawei Wang, Praneet Opanasopit, Jindřich Kopeček. Journal of Controlled Release. 2018, 293 (2019) pp 84-93. November 19, 2018.

The surface stress of biomedical silicones is a stimulant of cellular response. Zhu Cheng, Carolyn R. Shurer, Samuel Schmidt, Vivek K. Gupta, Grace Chuang, Jin Su, Amanda R. Watkins, Abhishek Shetty, Jason A. Spector, Chung-Yuen Hui, Heidi L. Reesink and Matthew J. Paszek. Science Advances. 2020. Vol. 6, no. 15, eaay0076. 10 Apr 2020. DOI: 10.1126/sciadv.aay0076.

Preclinical Development of a Fusion Peptide Conjugate as an HIV Vaccine Immunogen
Li Ou, Wing-Pui Kong, Gwo-Yu Chuang, Mridul Ghosh, Krishana Gulla, Sijy O’Dell, Joseph Varriale, Nathan Barefoot, Anita Changela, Cara W. Chao, Cheng Cheng, Aliaksandr Druz, Rui Kong, Krisha McKee, Reda Rawi, Edward K. Sarfo, Arne Schön, Andrew Shaddeau, Yaroslav Tsybovsky, Raffaello Verardi, Shuishu Wang, Timothy G. Wanninger, Kai Xu, Gengcheng J. Yang, Baoshan Zhang, Yaqiu Zhang, Tongqing Zhou, The VRC Production Program, Frank J. Arnold, Nicole A. Doria-Rose, Q. Paula Lei, Edward T. Ryan, Willie F. Vann, John R. Mascola & Peter D. Kwong. Scientific Reports . 2020. Article number: 3032 (2020). DOI: 10.1038/s41598-020-59711-y

DNA‐Mediated Assembly of Multispecific Antibodies for T Cell Engaging and Tumor Killing. Liqiang Pan, Chan Cao, Changqing Run, Liujuan Zhou, James J. Cho. Advanced Science. 2020. Volume7, Issue2 January 22, 2020, 1900973. November 23, 2019. DOI: 10.1002/advs.201900973

Rapid Gel Card Agglutination Assays for Serological Analysis Following SARS-CoV-2 Infection in Humans. Diana Alves, Rodrigo Curvello, Edward Henderson, Vidhishri Kesarwani, Julia A. Walker, Samuel C. Leguizamon, Heather McLiesh, Vikram Singh Raghuwanshi, Hajar Samadian, Erica M. Wood, Zoe K. McQuilten, Maryza Graham, Megan Wieringa, Tony M. Korman, Timothy F. Scott, Mark M. Banaszak Holl, Gil Garnier, and Simon R. Corrie. ACS Sens. 2020, 5, 8, 2596–2603. Publication Date:July 16, 2020

Visualizing multi-protein patterns at the synapse of neuronal tissue with DNA-assisted single-molecule localization microscopy. Kaarjel K. Narayanasamy, Aleksandar Stojic, Yunqing Li, Steffen Sass, Marina Hesse, Nina S. Deussner-Helfmann, Marina S. Dietz, Maja Klevanski, Thomas Kuner, Mike Heilemann. bioRxiv. 2021. DOI: 10.1101/2021.02.23.432306

Investigations into the Ice Crystallization and Freezing Properties of the Antifreeze Protein ApAFP752. Asenath-Smith, Emily Jeng, Emily C. Ambrogi, Emma K. Hoch, Garrett R. Olivier, Jason L., Engineer Research and Development Center (U.S.), ERDC/CRREL TR-22-17, 09/01/2022, 10.21079/11681/45620

Applicable patents and legal notices are available at legal notices.

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