t-Boc-Aminooxy-PEG4-CH2CO2H is a crosslinking reagent with a Boc-protected aminooxy group and a terminal carboxylic acid. The terminal carboxylic acid can react with primary amine groups in the presence of activators (e.g. EDC, or HATU). The Boc-protected amine can be deprotected under mild acidic conditions. PEG4 spacer increases solubility in aqueous media.
