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m-dPEG®₂₅-amido-dPEG®₂₄-TFP ester (QBD-11096)



m-dPEG®25-amido-dPEG®24-TFP ester, product number QBD-11096, is a long (153 atoms, 178.9 Å), methyl-terminated, discrete-chain-length polyethylene glycol (dPEG®) spacer functionalized with a 2,3,5,6-tetrafluorophenyl (TFP) ester for reaction with free amines. It is effectively a single molecular weight mPEG49 linker with an amide linkage in the middle of the discrete PEG chain. m-dPEG®25-amido-dPEG®24-TFP ester is just one member of an comprehensive line of methyl-terminated PEGylation reagents that includes dPEG® spacers containing 2 to 49 ethylene glycol units.

TFP esters react optimally with free amines at pH 7.5 – 8.0 and are generally more hydrolytically stable in water and aqueous buffers than NHS esters. In aqueous media, the hydrolytic rate of the ester to the carboxylic acid increases with increasing pH. Reacting surface amines on biomolecules (e.g., proteins and peptides) with this uncharged, methyl-capped dPEG® spacer may alter the overall charge of the resulting conjugates.

Many applications could employ m-dPEG®25-amido-dPEG®24-TFP ester, including the following:
dendrimer construction;
PK and immunogenicity improvements for dendrimers, peptides, and proteins;
cell surface engineering;
peptide synthesis and modification to improve water solubility or decrease immunogenicity;
coating of nanoparticles, quantum dots, and carbon nanotubes; and
prevention of protein aggregation.


Unit Size100mg, 1000mg
Molecular Weight2437.76; single compound
Chemical formulaC₁₀₉H₂₀₅F₄NO₅₂
Purity> 98%
SpacersdPEG® Spacer is 153 atoms and 178.9 Å
Typical solubility properties (for additional information contact Customer Support)Water, Dimethylacetamide, Acetonitrile, or Methylene Chloride
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.

Applicable patents and legal notices are available at legal notices.

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