Thermo Scientific™

TMS(PEG)12 Branched Methyl-PEG-NHS-Ester Reagent

Catalog number:  22424

 Related applications:

Protein Labeling & Crosslinking

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Thermo Scientific Pierce TMS(PEG)12 is a three-branched, polyethylene glycol compound (3 times 12 PEG units) activated as an NHS ester for covalent pegylation of primary amines (e.g., lysines) on proteins or assay surfaces.

Features of TMS(PEG)12:

• NHS-activated for efficient PEGylation of primary amines at pH 7-9; reaction of NHS-ester group results in formation of stable, irreversible amide 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

TMS(PEG)12 is the abbreviation for a branched trimethyl (TM) and succinimide ester (S) derivative of polyethylene glycol (PEG) for efficient and specific modification of primary amines. Each methyl-terminated PEG (mPEG) branch contains 12 ethylene glycol units. The three branches are attached to a 4-unit PEG stem that contains an amine-reactive N-hydroxysuccinimide (NHS) ester at the distal end. The NHS ester is spontaneously reactive with primary amines (—NH2), providing for efficient PEGylation of proteins, peptides and other amine-containing molecules or surfaces.

PEGylation Applications:
• 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.

TMS(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.

Related Products
MS(PEG)24 Methyl-PEG-NHS-Ester Reagent
For Research Use Only. Not for use in diagnostic procedures.


Chemical Reactivity: Amine
Product Size: 1 g

Contents & storage

Store desiccated at -20°C.


Manuals & protocols