Vector Labs is closed to observe Independence Day (US Holiday) on Thursday, July 4th.
We will be back in the office on Friday. We will respond to emails upon our return. Have a wonderful day.

Bromoacetamido-dPEG®₄-TFP ester (QBD-11200)



Bromoacetamido-dPEG®4-TFP ester, product number QBD-11200, is a short (18 atoms, 20.4 Å), single molecular weight, discrete PEG (dPEG®) crosslinker functionalized with a thiol-reactive bromoacetate group on one end and an amine-reactive 2,3,5,6-tetrafluorophenyl (TFP) ester on the other.

The short, flexible, non-immunogenic dPEG® crosslinker increases the hydrodynamic volumes of conjugates in aqueous media, thereby increasing water solubility. The increased hydrodynamic volume can reduce or eliminate conjugate molecules’ renal clearance and shield conjugates from opsonization.

The bromoacetate moiety is an alternative to the maleimide group, reacting chemoselectively with free thiols at pH ≥8.0. It is useful for situations where the conjugate molecule needs to be kept at a high pH (≥8.0), above the range where maleimides can be used effectively, or in constructs where maleimide groups are unstable.

TFP esters are an alternate reactive group to N-hydroxysuccinimidyl (NHS) esters and react with amines at an optimal pH range of 7.5 – 8.0, higher than the optimal range for NHS esters (pH 7.0 – 7.5). TFP esters are more hydrolytically stable than NHS esters, and they are more reactive toward amines in their optimal pH range than NHS esters are within the pH range 7.0 – 7.5.


Unit Size100 mg, 1000 mg
Molecular Weight534.29; single compound;
Chemical formulaC₁₉H₂₄BrF₄NO₇
Purity> 97%
SpacersdPEG® Spacer is 18 atoms and 20.4 Å
Typical solubility properties (for additional information contact Customer Support)Methylene Chloride, Methanol, MTBE, or Water.
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.

Applicable patents and legal notices are available at legal notices.

How do I Request a Quote?

To request a quote for products:

  1.  Sign in to
  2.  Add the items you wish to quote to the cart;
  3.  View your cart;
  4.  Click on the “Request a Quote” button found below the items in your cart;
  5.  Download your quote