Description

What is PEG?

PEG is the common abbreviation for PEGylation–or, more properly, poly(ethylene glycol)–which refers to a chemical compound composed of repeating ethylene glycol units.

Purified PEG is most commonly available commercially as mixtures of different oligomer sizes in broadly or narrowly defined molecular weight (M.W.) ranges. For example, "PEG**0" typically denotes a preparation that includes a mixture of oligomers having an average M.W. of **0. Likewise, "PEG****0" denotes a mixture of PEG molecules (n=******5) having an average M.W. of *0,**0g/mol.

Advantages of PEGylation

o Increased bioavailability

o Increased blood circulation of the target biomolecule / drug

o Shielding receptor-mediated uptake by the reticuloendothelial system (RES)

o Shielding of antigenic and immunogenic epitopes

o Preventing recognition and degradation by proteolytic enzymes

o Increasing the apparent size of polypeptides, thus reducing the renal filtration and altering biodistribution

o Optimized pharmacokinetics

o Decreased immunogenicity

Application of PEGylation

The protection of biological macromolecules, peptides, antibodies, proteins, and oligonucleotides is of extreme importance in biological, immunological and pharmacological applications.

There is growing interest of PEG and its α- and/or ω-substituted derivates and the protection offered by the covalent attachment of PEG to target molecules. PEGylation has become the method of choice for the delivery of bio-pharmaceuticals.

Linear PEGs can offer one or two reactive groups that can bind with a functional group on the target molecule.