Thermo Scientific Pierce SM(PEG)12 is a polypropylene glycol with N-hydroxysuccinimide (NHS) ester and maleimide Heterobifunctional cross-linking agent with amine group, capable of covalent coupling of molecules containing amine and sulfhydryl groups. Cross-linkers with polyethylene glycol (PEG) spacers are convenient alternatives to reagents with pure hydrocarbon spacers. The PEG spacer improves the aqueous solubility of the reagent and conjugate, reduces the potential for conjugate aggregation, and increases cross-linking flexibility, thereby reducing immunogenic responses to the spacer itself. In contrast to typical PEG reagents, which contain heterogeneous mixtures of different PEG chain lengths, Pierce PEGylation reagents are homogeneous compounds with defined molecular weights and spacer arm lengths, providing greater precision in the optimization and characterization of cross-linking applications. .

Thermo Scientific No-Weigh products are professional reagents provided in pre-packaged formats. Pre-weighed packaging eliminates repeated opening and closing of vials, preventing loss of reagent reactivity and contamination over time. With this format, a fresh vial of reagent can be used at a time, eliminating the hassle of weighing small amounts of reagent and reducing concerns about reagent stability.

Features of SM(PEG)12:

•Reactive groups:NHS Ester and Maleimide
•Reacts with:Amino and thiol groups
• Irreversibly cross-link proteins or peptides with flexible PEG spacers
• Polyethylene glycol spacers help maintain conjugate solubility
• Pure compounds with well-defined structure and molecular weight to ensure reproducibility Protein modification effects
• PEG spacers offer unique advantages, including increased stability, reduced tendency to aggregate, and reduced immunogenicity
• Ideal for performing controlled two-step protein coupling (see Sulfo-SMCC)

SM(PEG)n NHS- and maleimide-activated PEG compounds, Used to cross-link between primary amine (NH2) and sulfhydryl (SH) groups in proteins and other molecules. A comprehensive set of compounds is available, each with the same heterobifunctional structure (NHS-PEGn-maleimide) but with a different number of discrete ethylene glycol units (n = 2, 4, 6, 8, 12, or 24). The N-hydroxysuccinimide ester (NHS) group reacts specifically and efficiently with lysine and the N-terminal amino group at a pH value between 7 and 9 to form a stable amide bond. The maleimide group reacts with the reducing sulfhydryl group at pH 6.5-7.5 to form a stable thioether bond.

Synonyms for SM(PEG)n:
• NHS-dPEG-Mal
• Mal-PEG NHS Ester
• NHS-PEO-Maleyl Imines
• Succinimide-dPEG-Maleimide
• Succinimide-Maleimide PEG

Why use spacers containing polyethylene glycol (PEG) Arm cross-linker?
Proteins have been modified using PEG-containing reagents to provide specificity advantages. Protein PEGylation can improve the stability of the modified protein, making it immune to proteolytic enzyme cleavage, increasing its half-life in biological applications, masking the immunogenic response it causes, and reducing its antigenicity or potential toxicity. Improves its solubility, reduces the potential for aggregation, and minimizes interference in in vitro and in vivo applications. Polyethylene glycol has this effect because it is non-toxic, non-immunogenic, hydrophilic, water-soluble and highly flexible.

Advantages of Discrete Length Polyethylene Glycol Compounds:
These reagents are specially synthesized to produce homogeneous compounds with well-defined molecular weights characterized by discrete chain lengths, providing more Excellent ability to optimize and characterize surface protein modifications. Typical formulations of PEG compounds are heterogeneous mixtures containing a defined average molecular weight or approximate number of PEG subunits distributed in chain lengths.