N-terminal PEG Derivatives and PEGylation Reagents:
PEG NHS ester – N-hydroxyl succinimidyl ester (SCM, glutarate, succinate, glutaramide)
PEG aldehyde – PEG propionaldehyde
PEG ketone – PEG carbonyl
PEG carboxylic acid – carboxyl methyl, acetic acid, glutaric and succinic acid
PEG cyanur