Thermo Scientific™ SM(PEG)2 (PEGylated SMCC crosslinker)

The SM(PEG)_n reagents are six crosslinkers that have identical amine- and sulfhydryl-reactive groups but differ in length as a result of spacer arms composed of different numbers of ethylene glycol units. Their structures (shown below) have the form NHS-(PEG)_n-Maleimide, where n represents 2, 4, 6, 8, 12 or 24 polyethylene glycol (PEG) units. Each SM(PEG)_n reagent is produced at the specified length without contamination from analogs of other lengths.The availability of this set of reagents makes it possible to optimize crosslinking experiments to obtain the best conjugate efficiency and function for the intended application or analysis method. Considered together with AMAS (Part No. 22295) and the popular SMCC (Part No. 22360), these reagents allow for amine-to-sulfhydryl crosslinking across spaces ranging from 4.4 to 95.2Å. In addition, the hydrophilic PEG content of SM(PEG)_n reagents adds to the aqueous solubility of these crosslinkers and their conjugates. PEG is also less immunogenic than other types of crosslinker spacers, making these reagents ideal for immunogen preparation.

Highlights:

• Homologous series of increasing spacer arm length, ideal for optimizing conjugation of protein interactions
• Water-soluble polyethylene glycol (PEG) spacer arms help to maintain or increase solubility of crosslinked proteins
• Reagents readily dissolve in DMSO for subsequent dilution in aqueous reaction buffers
• Reactive groups: NHS ester and maleimide
• Reactive toward: amino and sulfhydryl groups

NHS-PEG₂-Maleimide

• Two ethylene oxide subunits
• Alternate names: Mal-dPEG₂-NHS, NHS-PEG₂-Maleimide
• Molecular formula C₁₈H₂₃N₃O₉
• Spacer arm length 17.6Å
• Mass added to target per crosslink 310.12
• MW 425.39

NHS-PEG₄-Maleimide

• Four ethylene oxide subunits
• Alternate names Mal-dPEG₄-NHS, NHS-PEG₄-Maleimide
• Molecular formula C₂₂H₃₁N₃O₁₁
• Spacer arm length 24.6Å
• Mass added to target per crosslink 398.17
• MW 513.50&

NHS-PEG₆-Maleimide

• Six ethylene oxide subunits
• Alternate names Mal-dPEG₆-NHS, NHS-PEG₆-Maleimide
• Molecular formula C₂₆H₃₉N₃O₁₃
• Spacer arm length 32.25Å
• Mass added to target per crosslink 486.20
• MW 601.60

NHS-PEG₈-Maleimide

• Eight ethylene oxide subunits
• Alternate names Mal-dPEG₈-NHS, NHS-PEG₈-Maleimide
• Molecular formula C₃₀H₄₇N₃O₁₅
• Spacer arm length 39.2Å
• Mass added to target per crosslink 574.27
• MW 689.71

NHS-PEG₁₂-Maleimide

• 12 ethylene oxide subunits Mal-dPEG₁₂-NHS, NHS-PEG₁₂-Maleimide
• Molecular Formula C₃₈H₆₃N₃O₁₉
• Spacer arm length 53.4Å
• Mass added to target per crosslink 750.38
• MW 865.92