Thermo Scientific Pierce MM(PEG)12 is a methyl-terminated, 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.
MM(PEG)n is the abbreviation for a set of compounds having polyethylene glycol (PEG) spacers with methyl (–CH3) and sulfhydryl-reactive maleimide groups at opposite ends. The unbranched, hydrophilic, discrete-length molecules have the form Methyl-PEGn-Maleimide, where the subscript "n" denotes 12 or 24 ethylene glycol units. 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
- Fully characterized PEGylation reagents with defined PEG chain lengths; molecules of discrete molecular weight for consistency of performance in protein-modification applications
- Provided with either 12 or 24 ethylene glycol units, enabling modification procedures to be optimized for a specific application while retaining all the benefits associated with protein PEGylation
- 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
|Chemical structures of Methyl-PEG-Maleimide reagents, MM(PEG)n. Alternative names include Mal-m-dPEG, Methyl-PEG-malemide, m-PEO-Mal, Maleimide PEG 600, PEG 1200 Maleimide, Maleimide-activated mPEG.
- PEGylate amine surfaces
- Add inert mass to proteins, immunogens, drug compounds and probes
- Improve solubility (decrease aggregation) of proteins or peptides without affecting function
- Protect proteins from proteolysis
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.
Advantages of Discrete-length mPEG-NHS Ester Compounds:
These reagents are specially synthesized as homogeneous compounds of discrete chain length and defined molecular weight. As such, they enable precise control and optimization of surface protein modification experiments. 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.
Protein PEGylation technical guide (and PEG reagent selection guide)