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Biotin-dPEG®₁₁-MAL (QBD-10195)


Biotin-dPEG®11-MAL, product number QBD-10195, is a medium-length, discrete PEG (dPEG®) biotinylation reagent that reacts with free thiols through the maleimido group in the pH range of 6.5 – 7.5, forming a stable thioether linkage.


Biotin-dPEG®11-MAL, product number QBD-10195, is one of three products containing a biotin on one end of a dPEG® linker and a maleimidopropyl moiety on the other end. The maleimide group is a useful, highly popular reactive group for conjugating to free thiol groups in biomolecules. This product provides a short-chain, single molecular weight, discrete PEG (dPEG®) spacer between the biotin and the maleimide. Maleimide groups can be conjugated to free thiol groups in the pH range from 6.5 – 7.5, forming a stable thioether linkage. The dPEG® spacer in this product increases the hydrophilicity of the conjugate.

This product has proven useful in a variety of applications that take advantage of the high streptavidin-biotin binding affinity. Such applications include magnetic bead-based assays, assays to quantitate reducible thiols in proteins, atomic force microscopy, and nanoparticle applications, among others.

To use Biotin-dPEG®11-MAL, the product should be dissolved in dry solvent and then added to an aqueous solution of the compound containing the free thiol. The water-miscible solvent N,N’-dimethylacetamide (DMAC) dried over 3Å molecular sieves is an excellent solvent to use for this purpose. For biomolecules (e.g., antibodies), care should be taken to keep the amount of organic solvent to a minimum so as not to denature the biomolecule or cause salt precipitation.


Unit Size25 mg, 100 mg
Molecular Weight922.09; single compound
Chemical formulaC₄₁H₇₁N₅O₁₆S
Purity> 98%
SpacersdPEG® Spacer is 43 atoms and 50.5 Å
Typical solubility properties (for additional information contact Customer Support)Methylene chloride, 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.


  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.
  2. A magnetic bead-based protein kinase assay with dual detection techniques. Guangchang Zhou, Juliesta E. Sylvester, Ding Wua, Darren R. Veach , Stephen J. Kron. Analytical Biochemistry. 2011, 1 (408), pp 5-11, January 2011. DOI: 10.1016/j.ab.2010.08.034.
  3. An Assay to Quantitate Reducible Cysteines from Nanograms of GST-Fusion Proteins. Dixon J. Woodbury, Chris A. Rees, Ammon Thompson, Paul Meiners, April Adams. Analytical Biochemistry. 2011, 417 (2) pp 165-173. October 15, 2011. DOI: 10.1016/j.ab.2011.06.017.
  4. The rotation-coupled sliding of EcoRV. Jasmina Dikic, Carolin Menges, Samuel Clarke, Michael Kokkinidis, Alfred Pingoud, Wolfgang Wende and Pierre Desbiolles. Nucleic Acids Research. 2012, 40 (9), pp 4064-4070. January 12, 2012. DOI:10.1093/nar/gkr1309.
  5. Fluorescent Silica Nanoparticles with Well-Separated Intensity Distributions from Batch Reactions. Teresa Kao , Ferdinand Kohle, Kai Ma, Tangi Aubert , Alexander Andrievsky, and Ulrich Wiesner. Nano Letters. 2018, 18, pp 1305-1310. January 2, 2018. DOI: 10.1021/acs.nanolett.7b04978.
  6. TCR Triggering by pMHC Ligands Tethered on Surfaces via Poly(Ethylene Glycol) Depends on Polymer Length. Zhengyu Ma, David N. Lebard, Sharon M. Loverde, Kim A. Sharp, Michael L. Klein, Dennis E. Discher, Terri H. Finkel. PLoS ONE. 2014. November 10, 2014. DOI: 10.137/journal.pone.0112292.
  7. Supramolecular Assembly of Three-Dimensional Protein Networks. Fatima Omar Merza. UWSPACE. 2020. 9/2/2020.
  8. Cohesin mediates DNA loop extrusion by a “swing and clamp” mechanism. Benedikt W Bauer, Iain F Davidson, Daniel Canena, Gordana Wutz, Wen Tang, Gabriele Litos, Sabrina Horn, Peter Hinterdorfer, Jan-Michael Peters. Cell. 2021. Volume 184, Issue 21. October 07, 2021. DOI:
  9. Structural determinants of the integrin transmembrane domain required for bidirectional signal transmission across the cell membrane. Zhengli Wang, Jieqing Zhu. Journal of Biological Chemistry. 2021. Volume 297, Issue 5. October 20, 2021. DOI:

Applicable patents and legal notices are available at legal notices.

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