Difference Between Polymer PEG (Polydisperse PEG) and Monodisperse PEG

The polymer PEG is a polyethylene glycol (PEG) polymer, a polyether compound derived from petroleum that has many applications ranging from industrial manufacturing to medicine. The average molecular weight is 2K, 5K, 10K, 20K, and the PDI is 1.01-1.10. Polymer PEG is also called polydisperse PEG. It exists in many shapes, including star shape, branched chain, Y shape, etc. It can be attached with a variety of functional groups.

Polymer PEG Typical functional groups include Acrylate, alkyne, Amine, Azide, DBCO, TCO, Aldehyde, Acid, NHS ester, Hydrazide, Maleimide, Silane, Biotin, Tos, or Thiol.

Polymer PEG have become especially attractive tools in various pharmaceutical, biological and chemical industry application due to its aqueous solubility, high flexibility and non-immunogenicity.

Difference from Monodisperse PEG:
Monodisperse PEG refers to polyethylene glycol with precise discrete molecular weights (ie, the molecular weight is a fixed value, rather than a range), and is a pure compound with an exact molecular configuration. The molecular weights of polydisperse PEGs are described in terms of distribution ranges. Molecular weight distribution is usually confirmed by the dispersion coefficient (PDI).

At present, most of the polyethylene glycol compounds supplied on the market are polymers formed by the polymerization of ethylene glycol. The molecular weight of polymer PEG compounds is uncertain, and distributed in a certain range. It will be difficult to quantify the modified compounds in practice because of disperse molecular weight. In addition, it is very difficult to separate and purify polyethylene glycol compounds because of their similar structure, so it is particularly important to design a synthesis method of monodisperse polyethylene glycol(PEG) derivatives.

Monodisperse polyethylene glycol(PEG) molecular weight is fixed. It can not be obtained by polymerization. It must be by the appropriate reaction of the basic polyethylene glycol fragment.

Monodisperse PEG products usually are organic compounds with a molecular weight of less than 1000. Monodisperse PEGs do not have the polydispersity of general PEG polymers, and retain the good solubility of polyethylene glycol in water. It can also impart flexibility, anticoagulation, anti-macrophage phagocytosis, etc., to modified biomolecules. This provides PEGylated drugs with the same PEG that reduces polymerization and immunogenicity.

Monodispersed PEGs have been applied in many fields, including medical research, drug-release, nanotechnology, etc. And they have been become very beneficial in drug design and development, specifically in the antibody-drug conjugates and small molecule drugs.

Axispharm offers a wide range of PEG polymers, including various functional PEG polymers suitable for your applications in the pharmaceutical, biological and chemical industries. You may also be interested in the following products provided by Axispharm: maleimide linker, azido peg, spdp linker, azide linker, dbco linker, cleavable peg linker, aminooxy peg, etc. If you have any questions about peg linkers, feel free to contact us.