Peptide Knowledge Center

PEGylation of Protein Drugs

Polyethylene glycol (PEG) has the advantages of non-toxicity, non-immunity, non-antigenicity and good solubility in water, so it is approved by the FDA as a modifier of drugs.

The PEG modification of protein drugs has developed rapidly, and successfully developed polyethylene glycol-modified acyl glucoside deaminase (PEG-ADA), asparaginase (PEG-L-asparaginase), interferon α-2b (peginterferon alfa) -2b), interferon alpha-2a (peginterferon alfa-2a), recombinant human granulocyte colony stimulating factor (pegfilgrastim), camptothecin (PEG-CPT), doxorubicin liposome and other protein drugs. Protein drugs modified by polyethylene glycol (PEG) can significantly prolong the action time, enhance water solubility and stability, and reduce immunogenicity and antigenicity


Bifunctional Grade PEG Derivatives

aaPEG(NH2-PEG - NHCO - CH2CH2COOH), and then react with Boc2O to protect the amino group to obtain Boc-aaPEG. This monomer is incorporated into the peptide chain in solid phase synthesis.

This method provides a method for modifying the middle position of the peptide chain; it also provides a method for linking two different peptide chains together through PEG. This makes PEG equivalent to a bridge, and the two ends of the bridge head are followed by peptide chains with different biological activities, which can be used to increase or expand the biological activity of the polypeptide.


N-terminal modification

Lu et al. used mPEG(CH3O-PEG) carboxyl derivatives, mPEG-O-CH2COOH and mPEG-O-CH2CO-Nle-OH, as monomers coupled to the N-terminus in solid-phase synthesis. The latter monomer was introduced into Nle to facilitate the detection of the degree of PEG modification of the polypeptide. Lu et al. modified the N-terminal PEG of the listed peptide drug human parathyroid hormone (1-34), and added a cysteine to the peptide chain during solid-phase synthesis. The purified peptide was cleaved and purified with mPEG5000 under weak alkaline conditions -MAL reaction to obtain the modified product.


From custom peptide synthesis - Omizzur Biotech