Bromoacetamido-dPEG®12-Tris(-dPEG®11-amido-bromoacetamide)3, product number 11433, is a branched, single molecular weight, thiol-reactive, discrete polyethylene glycol (dPEG®) product consisting of four (4) branched dPEG® arms built around a tris core. Each arm terminates with a thiol-reactive bromoacetyl group. Furthermore, each arm is 42 atoms long (53.5 – 54.5 Å) from the tris core to the methylene group adjacent to the bromine atom.
Traditional polyethylene glycol (PEG) is a disperse polymer (Đ > 1). A traditional PEG of a stated molecular mass is actually an average mass drawn from a rather large number of different chain lengths of PEG, each chain having its own molecular mass. This dispersity makes analysis of bioconjugate products challenging.
In sharp contrast to traditional PEG, Quanta BioDesign’s dPEG® products have no dispersity (Đ = 1). Each dPEG® product is a single molecular weight compound. Moreover, we do not purify a single molecular weight of PEG out of a complex polymeric mixture. Rather, we build up our products from ultrapure starting materials and maintain uniform product purity throughout the synthetic, workup, and purification steps leading to the final product. For more information about our dPEG® technology, please click here. For answers to frequently asked questions, please click here.
The four arms of Bromoacetamido-dPEG®12-Tris(-dPEG®11-amido-bromoacetamide)3 are built from a tris(hydroxymethyl)aminomethane (“tris”) core. Although one arm is differently structured than the other three arms (one dPEG®12 arm vs three dPEG®11 arms), each arm contains 42 atoms and has the same length when measured from the methylene unit adjacent to the bromine atom to the tris core from which each arm branches. The discrete chain lengths of each dPEG® spacer enable such precise construction. Such precision is not possible with traditional, dispersed polymer PEG.
The bromoacetyl group reacts chemoselectively with thiols at pH ≥ 8.0 to form a stable thioether linkage. To learn more about the reaction of the bromoacetyl group with thiols, go to Bromoacetyl Reaction Chemistry.
If you need bulk product in a larger package size than our standard sizes, please contact us for a quote. Our commercial capabilities permit us to manufacture this product at any scale that you need.
Hermanson, G. T. Chapter 2, Functional Targets for Bioconjugation. Bioconjugate Techniques, 3rd edition. Academic Press: New York, 2013, 127-228, specifically pages 191-192 discussing bromoacetyl and iodoacetyl reactions with thiols. Click here now for a review of Greg’s book and a link to purchase it.
Hermanson, G. T. Chapter 3, The Reactions of Bioconjugation. Bioconjugate Techniques, 3rd edition. Academic Press: New York, 2013, 229-258, specifically page 241, discussing maleimide reactions.
Hermanson, G. T. Chapter 8, Dendrimers and Dendrons. Bioconjugate Techniques, 3rd edition. Academic Press: New York, 2013, 351-386.
Hermanson, G. T. Chapter 18, PEGylation and Synthetic Polymer Modification. Bioconjugate Techniques, 3rd edition. Academic Press: New York, 2013, 787-838.