Although PEGylation remains an excellent choice for protein stabilization and controlled dosage of protein drugs, however,
it still poses a number of challenges. Manufacturing costs of goods, PEG polydispersity, drug clearance from the body, and
loss of biological activity resulting from PEGylation are just a few of the areas in need of further investigation. Because
of the improvement of PEG purification processes, the commercially available PEGs are nowadays less polydisperse, allowing
for larger molecular weight polymers to be used. In addition, the use of branched PEGs and the development of robust site
specific PEGylation have expanded and will continue to expand the polymer options available for protein PEGylation. Bigger
and better PEGs would require better characterization of the overall structural properties of the PEG and the conjugated complex.
A conformational approach to PEGylated species equilibrium offers insight into alternative options for optimization of the
A. Sorina Morar, PhD,
is a scientist, Process Development, Diosynth Biotechnology, 3000 Weston Parkway, Carey, NC 25713, 919.388.5649, fax: 919.678.0366, firstname.lastname@example.org
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