Thermo Scientific Pierce SM(PEG)n is a series of polyethylene glycol units containing n equal to 2 to 24. The alcohol spacer arm resulted in amine-thiol cross-linkers with lengths ranging from 17.6 to 95.2 Å.

Feature 4 of SM(PEG):

•Reactive group: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 pH 7-9 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.

Related products
SM(PEG)2 (polyethylene Glycolated SMCC cross-linker)
SM(PEG)6 (PEGylated long chain SMCC cross-linking agent)
SM(PEG)8 (PEGylated long-chain SMCC cross-linking agent) combination agent)