HO-PEG4-Benzyl Ester contains a hydroxy group and a benzyl protected carboxylic acid. The benzyl is easily removed under mild deprotection condition to afford a free acid that can be used to conjugate with an amine-bearing biopolymer, such as protein, oligonucleotide, etc. The hydroxy group can be derivatized to more reactive functional groups. The PEG spacer adds aqueous solubility to the newly formed complex.
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.