PEG Linkers

PEG Linkers

PEG linkers are chemically functionalized polyethylene glycol (PEG) linkers. PEG linkers are particularly attractive as very powerful tools in scientific community for conjugation, drug discovery, nanoparticle drug delivery, chemical biology and biolabeling due to their aqueous solubility and non-immunogenicity.

There are two classes of PEG, monodispersed and poly-dispersed. A monodispersed PEG linker has an exact number of PEG units with a specific chemical structure and a precise molecular weight. Whereas a poly-dispersed PEG (also known as Polymer PEG or PolyPEG) is a polymer with an averaged molecular weight.

Example of Monodispersed PEG Linkers

azido-peg4-nhs ester
Figure 1. Azido-PEG4-NHS ester is a popular monodisperse PEG linker with azide and NHS groups.

As a leading PEG supplier worldwide, BroadPharm has over 4,000 high purity PEG linkers in stock for overnight shipping. These products cover a wide range of functional groups, such as Azide, Amine, Alkyne, DBCO, TCO, NHS ester, Maleimide. You can also select the desired PEG length based on your needs. Please review the listed products as below.

PEG Linkers(In Stock)

PEG Linkers have become widely used in drug discovery, ADC development, bioconjugation and labeling, nanoparticle drug delivery, and PEGylation.

Examples of PEG in Application:

PEG in Antibody Drug Conjugate

In antibody drug conjugates (ADCs), the Linker between antibody and payload can significantly affect the potency, stability, selectivity, and DMPK of an antibody-drug conjugate. For example, ADC drug Zynlonta has incorporated several interesting linker components including the maleimide PEG8 with enzymatically cleavable linkers (Val-Ala) that connect the payload to the antibody (Figure 2).

Figure 2. Zynlonta, shown above, has maleimide-peg8 linkers between antibody and payload SG319 PBD dimer.

PEG in Nanoparticle Drug Delivery

Lipid nanoparticle drug delivery has now become famous with the development of Moderna and Pfizer COVID-19 vaccines (Figure 3). Typically, the delivery system are composed of a high transition temperature phospholipid, a PEG lipid, and an ionizable cationic phospholipid. One specific example is DSPE-mPEG 2000, which is essential to producing the Pfizer COVID-19 vaccine. Another well-known PEGylated lipid is DMG-PEG 2000, which is used in the Moderna COVID-19 vaccine.

Figure 3. PEG Lipids used in COVID-19 vaccines, Pfizer's DSPE-PEG 2000 shown on top and Moderna's DMG-PEG 2000 shown on bottom.

PEG in Small Molecule Drug

Introduction of PEG linkers to small molecule drugs increases the drug's solubility and molecular weight. It allows for an extended drug half-life in the body. Naloxegol (Movantik) is one example of a small molecule drug that incorporates PEG to improve the drug's efficiency by reducing its transport across the blood-brain barrier (Figure 4).

Figure 4. Movantik, is a pegylated derivative of α-naloxol.

Examples of Popular PEG Linkers:

Catalog Product Name Structure M.W. Purity Pricing
BP-20518Azido-PEG4-NHS ester388.498%Pricing
BP-21606Azido-PEG8-NHS ester564.698%Pricing
BP-22418TCO-PEG4-NHS ester514.695%Pricing
BP-24081endo-BCN-PEG2-NHS ester450.597%Pricing
BP-21634Fmoc-PEG8-NHS ester760.898%Pricing