Bis-Mal-Lysine-PEG4-TFP ester contains two maleimide groups which can be reacted with thiols from pH ranges of 6.5 to 7.5 to from a thiolether bond. The terminal carboxylic acid can react with primary amines in the presence of activators such as EDC and DCC to form stable amide bonds. The hydrophilic PEG linker can increase the water solubility of a compound in aqueous media.
Axispharm offers 3000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.