Tos-PEG22-Tos linker contains two tosyl groups. The tosyl group can be easily replaced by thiol and amino group through a nucleophilic substitution.The PEG spacer increases the aqueous solubility of the resulting compound.
Axispharm offers 3000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.