m-PEG37-hydrazide is a PEG linker containing a hydrazide end group. Hydrazine moieties react with an aldehyde to form semi-permanent hydrazone bonds. The hydrophilic PEG chain increases the water solubility of the compound. Longer PEG chains have better solubility properties relative to shorter PEG chains. Reagent grade, for research purpose. Please contact us for GMP-grade inquiries.