The aldehyde group readily reacts with primary amines, aminooxy and hydrazide. After a hydrazine deprotection, the free oxyamine group that can react with an aldehyde to form a reversible oxime bond. If reduced, the oxime can be converted to a stable carbon-N bond. The PEG spacer increase the solubility of the resulting complex in aqueous media.
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.