Mal-amido-PEG4-TFP ester linker contains a maleimide and TFP ester end group. Maleimide groups readily reacts with thiols between pH 6.5 and 7.5 to form S-C bond. The TFP ester can be reacted with primary amine groups and is also less susceptible to undergo hydrolysis compared to NHS ester. The PEG spacer increase the solubility of the compound in aqueous media.
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.