Thermo Scientific Pierce TMM(PEG)12 is a three-branched, polyethylene glycol compound (3 times 12 PEG units) activated with a maleimide group for covalent pegylation of sulfhydryls on proteins (e.g., cysteines) or assay surfaces.
TMM(PEG)12 is the abbreviation for a branched trimethyl (TM) and maleimide (M) derivative of polyethylene glycol (PEG) for efficient and specific modification of sulfhydryl groups. Each methyl-terminated PEG (mPEG) branch contains 12 ethylene glycol units. The three branches are attached to a 4-unit PEG stem that contains a sulfhydryl-reactive maleimide group at the distal end. The maleimide is spontaneously reactive with sulfhydryl (–SH) groups, providing for efficient PEGylation of proteins, peptides and other cysteine- or thiol-containing molecules.
- Maleimide-activated for efficient PEGylation of sulfhydryl groups at pH 6.5-7.5; reaction of maleimide group results in formation of stable, irreversible thioether bonds
- Pure compound with defined structure and molecular weight, ensuring reproducible protein-modification effects
- PEG spacer provides unique advantages, including increased stability, reduced tendency toward aggregation and reduced immunogenicity
- Easy-to-follow instructions increase the likelihood of a successful outcome
- Cap and PEGylate reduced sulfhydryl groups (e.g., cleaved disulfide bonds)
- Add inert mass to proteins, immunogens, drug compounds and probes
- Improve solubility (decrease aggregation) of proteins or peptides without affecting function
- Prevent disulfide bond formation while increasing mass and hydrophilicity
- Protect proteins from proteolysis
Alternative Names for TMM(PEG)12:
- Branched mPEG maleimide
- Maleimide-activated PEG 2000
Why PEGylate a protein or peptide?
PEG-containing reagents have been used to modify proteins to provide specific advantages. Protein PEGylation can improve the stability of the modified protein, protect it from proteolytic digestion, increase its half life in biological applications, mask it from causing an immunogenic response, decrease its antigenicity or potential toxicity, improve its solubility, diminish the potential for aggregation, and minimize interference for both in vitro and in vivo applications. Polyethylene glycol, also called polyethylene oxide (PEO), has these effects because it is nontoxic, nonimmunogenic, hydrophilic, water soluble and highly flexible.
TMM(PEG)12 is specially synthesized as a homogeneous compound of discrete chain length and defined molecular weight. By contrast, typical preparations of PEG compounds are heterogeneous mixtures composed of multiple chain lengths and a range of molecular weights.
- Hermanson, G.T. (2008). Bioconjugate Techniques, Academic Press (Part No. 20036)
- Harris, J. M. and Zalipsky, S. Eds (1997). Poly(ethylene glycol), Chemistry and Biological Applications, ACS Symposium Series, 680.
- Harris, J. M. and Kozlowski, A. (2001). Improvements in protein PEGylation: pegylated interferons for treatment of hepatitis C. J. Control Release 72, 217-224.
- Veronese, F. and Harris, J.M. Eds. (2002). Peptide and protein PEGylation. Advanced Drug Delivery Review 54(4), 453-609.
Linear maliemide-activated PEG Reagents, MM(PEG)n
Amine-reactive, branched PEGylation Reagent, TMM(PEG)n
Other Kinds of PEGylation Reagents