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Fmoc-N-amido-dPEG®₁₂-acid (QBD-10283)



Fmoc-N-amido-dPEG®12-acid, product number QBD-10283, is one of a broad line of products designed for use in peptide synthesis. The medium-length (40 atoms), discrete PEG (dPEG®) spacer is functionalized with a propionic acid group on one end and Fmoc-protected amine on the other. The compound can be added to the N-terminus of a growing peptide chain or to a primary-amine-functionalized side chain of an amino acid such as lysine. The dPEG®12 spacer imparts water solubility to the peptide to which it is conjugated.

QBD-10283 permits our customers to insert a medium-length (40 atoms) dPEG® into a peptide chain using familiar Fmoc chemistry. The product works equally well in solid phase and solution phase synthetic processes. The dPEG® can be inserted at either end of the peptide chain or in the middle of two amino acid sequences to provide a flexible spacer between distinct functional peptides. Additionally, the dPEG® spacer can be used to provide spacing in a synthetic construct where steric hindrance is a problem. The amphiphilic nature of dPEG® means that the construct will gain water solubility while remaining soluble in organic solvent. The Fmoc protecting group removes easily with a solution of piperidine in N,N-dimethylformamide (DMF).


Unit Size100 mg, 1000 mg
Molecular Weight839.96; single compound
Chemical formulaC₄₂H₆₅NO₁₆
Purity> 98%
SpacersdPEG® Spacer is 40 atoms and 46.5 Å
Typical solubility properties (for additional information contact Customer Support)Methylene chloride, Acetontrile, 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, 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.

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Neutrophil Targeting Heterobivalent SPECT Imaging Probe: cFLFLF-PEG-TKPPR-99mTc. Yi Zhang, Li Xiao, Mahendra D. Chordia, Landon W. Locke, Mark B. Williams, Stuart S. Berr, and Dongfeng Pan. Bioconjugate Chemistry. 2010, 21 (10), pp 1788–1793 September 15, 2010. DOI: 10.1021/bc100063a.

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Enhanced Cellular Uptake of Peptide-Targeted Nanoparticles through Increased Peptide Hydrophilicity and Optimized Ethylene Glycol Peptide-Linker Length. Jared F. Stefanick, Jonathan D. Ashley, and Basar Bilgicer. ACS Nano. 2013, 7 (9) pp 8115–8127. August 29, 2013. DOI: 10.1021/nn4033954.

Oriented Surface Immobilization of Antibodies at the Conserved Nucleotide Binding Site for Enhanced Antigen Detection. Nathan J Alves, Tanyel Kiziltepe, and Basar Bilgicer. Langmuir. 2012, 28 (25) pp 9640–9648. May 21, 2012. DOI: 10.1021/la301887s.

Hepatocyte Targeting of Nucleic Acid Complexes and Liposomes by a T7 Phage p17 Peptide. So C. Wong, Darren Wakefield, Jason Klein, Sean D. Monahan, David B. Rozema, David L. Lewis, Lori Higgs, James Ludtke, Alex V. Sokoloff, and Jon A. Wolff. Molecular Pharmaceutics. 2006, 3 (4) pp 386-397. March 28, 2006. DOI: 10.1021/mp050108r.

Evaluation of Nonpeptidic Ligand Conjugates for SPECT Imaging of Hypoxic and Carbonic Anhydrase IX-Expressing Cancers. Peng-Cheng Lv, Karson S. Putt, and Philip S. Low. Bioconjugate Chemistry. 2016, 27, pp 1762-1769. June 30, 2016. DOI: 10.1021/acs.bioconjchem.6b00271.

Synthesis of the Cyanine 7 labeled neutrophil-specific agents for noninvasive near infrared fluorescence imaging. Xiao L, Zhang Y, Liu Z, Yang M, Pu L, Pan D. Bioorganic & Medicinal Chemistry Letters. 2010, 20 (12) pp 3515-3517. June 15, 2010. DOI: 10.1016/j.bmcl.2010.04.136.

PEG-Peptide Conjugates. Ian W Hamley. Biomacromolecules. 2014, 15 (5) pp 1543-1559. April 1, 2014. DOI: 10.1021/bm500246w.

Controlled liposome fusion mediated by SNARE protein mimics. Hana Robson Marsden, Alexander V. Korobko,Tingting Zheng, Jens Voskuhla and Alexander Kros. Biomaterials Science. 2013, 1 (10) pp 1046-1054. June 4, 2013. DOI: 10.1039/C3BM60040H.

SNARE protein analog-mediated membrane fusion. Pawan Kumar, Samit Guha and Ulf Diederichsen. Journal of Peptide Science. 2015, April 7, 2015. DOI: 10.1002/psc.2773.

In Situ Modification of Plain Liposomes with Lipidated Coiled Coil Forming Peptides Induces Membrane Fusion. Frank Versluis , Jens Voskuhl , Bartjan van Kolck , Harshal Zope , Marien Bremmer , Tjerk Albregtse and Alexander Kros. Journal of the American Chemical Society. 2013, 135 (21), pp 8057–8062. May 9, 2013. DOI: 10.1021/ja4031227.

A Reduced SNARE Model for Membrane Fusion. Hana Robson Marsden, Nina A. Elbers, Paul H., H. Bomans, Nico A.J.M.Sommerdijk and Alexander Kros. Communications. 2009, 48 pp 2330-2333. February 16, 2009. DOI: 10.1002/anie.200804493.

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Bioresponsive nanocarries for targeted intracellular delivery of proteins and peptides. Ruth Elisabeth and Johanna Roder. Dissertation zur Erlangung des Doktorgrades der Fakultat fur Chemie und Pharmazie der Ludwig-Maximilians-Universitat Munchen. 2016, pp 1-128.

Bioresponsive nanocarries for targeted intracellular delivery of proteins and peptides. Ruth Elisabeth and Johanna Roder. Dissertation zur Erlangung des Doktorgrades der Fakultat fur Chemie und Pharmazie der Ludwig-Maximilians-Universitat Munchen. 2016, pp 1-128.

Influence of Defined Hydrophilic Blocks within Oligoaminoamide Copolymers: Compaction versus Sheilding of pDNA Nanoparticles. Stephan Morys, Ana Krhac Levacic, Sarah Urnauer, Susanne Kempter, Sarah Kern, Joachim O Radler, Christine Spitzweg, Ulrich Lachelt, and Ernst Wagner. Polymers. 2017, 9 (4) pp 1-20. April 19, 2017. DOI: 10.3390/polym9040142.

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Morphological Transformation of Peptide Nanoassemblies through Conformational Transition of Core-forming Peptides. Tomonori Waku, Naoyuki Hirata, Masamichi Nozaki, Kanta Nogami, Shigeru Kunugi and Naoki Tanaka. Polymers. 2018, 11 (1), 39. December 28, 2018.

Membrane-Fusogen Distance Is Critical for Efficient Coiled-Coil-Peptide-Mediated Liposome Fusion. Geert A. Daudey, Harshal R. Zope, Jens Voskuhl, Alexander Kros , and Aimee L. Boyle. Langmuir. 2017, 33 (43) pp 12443-12452. 10/5/2017. DOI: 10.1021/acs.langmuir.7b02931.

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Coiled-coil formation of the membrane-fusion K/E peptides viewed by electron paramagnetic resonance. Pravin Kumar, Martin van Son, Tingting Zheng, Dayenne Valdink, Jan Raap, Alexander Kros, and Martina Huber. PLOS ONE. 2018, 13 (1) pp 1-13. January 19, 2018. DOI: 10.1371/journal.pone.0191197.

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Polymer Cancerostatics Containing Cell-Penetrating Peptides: Internalization Efficacy Depends on Peptide Type and Spacer Length. Eliška Böhmová ,Robert Pola, Michal Pechar, Jozef Parnica, Daniela Machová, Olga Janoušková and Tomáš Etrych. Pharmaceutics 2020, 12(1), 59; January 10, 2020.

A Novel Bivalent Mannosylated Targeting Ligand Displayed on Nanoparticles Selectively Targets Anti-Inflammatory M2 Macrophages. Peiming Chen, Xiaoping Zhang, Alessandro Venosa, In Heon Lee, Daniel Myers, Jennifer A. Holloway, Robert K. Prud’homme, Dayuan Gao, Zoltan Szekely, Jeffery D. Laskin, Debra L. Laskin, and Patrick J. Sinko. Pharmaceutics 2020, 12(3), 243. March 8, 2020. DOI: 10.3390/pharmaceutics12030243

A New NT4 Peptide-Based Drug Delivery System for Cancer Treatment. Jlenia Brunetti, Sara Piantini, Marco Fragai, Silvia Scali, Giulia Cipriani, Lorenzo Depau, Alessandro Pini, Chiara Falciani, Stefano Menichetti and Luisa Bracci. Molecules 2020, 25(5), 1088; February 28, 2020. DOI: 10.3390/molecules25051088

Efficient capture of circulating tumor cells with low molecular weight folate receptor-specific ligands. Yingwen Hu, Danyang Chen, John V Napoleon, Madduri Srinivasarao, Sunil Singhal, Cagri A Savran, Philip S Low. Scientific Reports. 2022. May 20, 2022.

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