Polymer PEG

Polymer PEG

Polymer PEG is a Polyethylene glycol (PEG) polymer with an averaged molecular weight, such as 2K, 5K, 10K, 20K with PDI ranging from 1.01-1.10. Polymer PEG is also known as polydisperse PEG, or Poly-PEG.

There are different shapes of Polymer PEG, such as linear, Y-shaped, branched, or star shaped with different PEG chain lengths as shown in Figure 1. PEG chain can be attached with different functional groups for chemistry modification and industrial application.

Figure 1. Examples of Polymer PEG that are commercially available. 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

Polymer PEG(Polydisperse PEG)

Copolymer PEG

Amphiphilic block copolymer (ABC) is a unique class of polymer characterized by a hydrophilic block that is chemically bound to a hydrophobic block. Each block of the polymers may have molecular weight range from 1,000-20,000. In aqueous media, ABC is able to self-assemble into a wide range of nano-sized structures, such as nanoparticles, micelles, and polymersomes.

Biodegradable amphiphilic block copolymers

Figure 2. Biodegradable amphiphilic block copolymers (ABCs): (A) PLA-PEG, (B) PCL-PEG, and (C) PLGA-PEG.


Polymer PEG in applications

PEG in surface modification

PEG Silanes are a class of PEG linkers that can modify glass, silica and other surfaces or form useful structural systems on their own for encapsulation or research purposes. The chemistry went through the reaction of silane alkoxy group with water and then coating surface, the other end of PEG silane could be methoxy group or a reactive functional group such as Azido, Propargyl, Biotin, etc.  The PEG chain can also have a wide range of chain length, with the PEGylation greatly suppressing the non-specific binding of charged molecules to the modified surfaces, as shown in Figure 3.

PEG silane compounds
Figure 3. The PEG silane compounds adhere to a surface by first undergoing hydrolysis in an aqueous solution. The PEG silane molecules then form groups through condensation, which then bond to the surface of any suitable substrate.

The application of PEG silane compounds has varied widely. In one example, Lysine nitrilotriacetic acid (NTA) modified PEG silane was shown to be capable of efficiently immobilizing soluble and integral membrane proteins on a silica surface through metal-mediated complexation. This work helps further the research towards the practical realization of membrane protein-based biosensors. Another example of PEG silane compound application is in improving battery design by acting as a semi-permeable, covalently linked separator between the cathode and anode. This coating allows lithium ions to travel between the electrodes during battery use.

PEG in Protein PEGylation

Nyvepra is an example of pegfilgrastim, which is a PEGylated protein drug that serves to stimulate the production of white blood cells (Figure 4). It is comprised of the recombinant human granulocyte colony-stimulating factor (GCSF) analog and a 20,000 MW m-PEG polymer attached to the N-terminus region of the molecule. With the addition of PEG the medication has a dramatically increased half-life in the body.

Diagram of Nyvepria
Figure 4. Nyvepria, shown above, is a covalent conjugate of recombinant methionyl human granulocytecolony stimulating factor (G-CSF) (referred to as filgrastim) and a 20 kDa monomethoxypolyethylene glycol propionaldehyde (mPEG-p).

Polymer PEG in Nanoparticle Drug delivery

Polymer PEG is also used in nanoparticle drug delivery such as the most advanced Covid-19 vaccine mRNA delivery (Figure 5). PEG lipids have been used extensively to improve circulation times for liposome encapsulated (LNP) drugs and reduce non-specific uptakes.

PEG Lipids used in COVID-19 vaccines
Figure 5. PEG Lipids used in COVID-19 vaccines, Pfizer’s DSPE-PEG 2000 shown on top and Moderna’s DMG-PEG 2000 shown on bottom.

As a worldwide leading PEG supplier, BroadPharm not only provides monodisperse PEG linker with selection of PEG1 to PEG36, we also offers a wide array of polydisperse polymer PEG reagents to empower our customer’s advanced research. These compounds feature great aqueous solubility, with molecule weigh selection of PEG 2K, 5K, 10K, 20K and a broad selection of functional groups to choose from.