Hydroxy-PEG5-methyl ester linker contains a hydroxyl group and a methyl ester. The PEG spacer increases the aqueous solubility of the resulting compound. The hydroxyl group can be derivatized to other reactive functional groups for conjugation. Methyl ester can be hydrolyzed under strong basic condition to form a free acid, which can under amide coupling with amine bearing biomolecules.
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.