BOC Sciences provides high purity PEG linkers with multifunctional groups for your research on PEGylation, ADC linker, click chemistry, mRNA vaccine, etc.

What Are PEG?

Polyethylene glycol (PEG), a compound composed of repeated ethylene glycol units [-(CH2CH2O)n], is also known as Macrogols. PEG and PEG derivatives have the characteristics of non-irritation, good water solubility, good compatibility, etc. At the same time, they possess excellent lubricity, moisture retention, and dispersibility so that they can be used as adhesives, antistatic agents and softeners, and widely applied in cosmetics, pharmaceuticals, chemical fibers, rubber, plastics, paper, paint, electroplating, pesticides, metal processing and food processing industries.

Synthesis of PEG
PEG can be synthesized via anionic polymerization of ethylene oxide and any hydroxyl initiators. Hydroxyl group could be from water or ethylene glycol or any diols. They can also be derived from epoxyethane by ring-opening polymerization. Usually, the polymerization process produces a family of PEG molecules with wide Gaussian's distribution of molecular weights. PEG bears only two functional groups limiting the scope for further derivatization with other residues or targeting ligands. Therefore, commercial PEGs are available with different degrees of polymerization and activated functional groups.

PEG Properties
PEG earns its fame because of its high structure flexibility, biocompatibility, amphiphilicity, devoid of any steric hindrances, and high hydration capacity. PEG is soluble in water, ethanol and many other organic solvents, like DMF, dichloromethane, toluene, acetonitrile, acrylonitrile, etc. . It shows little toxicity and can be eliminated from the body intact by either the kidneys (for PEGs 30 kDa) or in the faeces (for PEGs 20 kDa). Other than that, PEG is also non-irritating and stable to heat, acid and alkali, thus it can be widely used in various pharmaceutical applications.



PEG, a polyether backbone polymer, is synthesized by ring opening polymerization of ethylene oxide using in common cases or usually methanol or water as an initiator. The reaction gives products with one or two end chain hydroxyl groups termed monomethoxy-PEG (mPEG-OH) or diol-PEG (HO-PEG-OH), respectively (Fig. 2).

The lone hydroxyl group in the case of the methoxy form, or the two in the case of PEG diol, can be modified to

be reactive towards different chemical groups by several activation strategies. Nowadays, a number of activated PEGs are commercially available. These derivatives are commonly monofunctional, either in their linear or branched structure. The chemical structures of several key PEG derivatives are shown in Figure 2. These derivatives are mainly known by their Mw.

PEGylation Technique
PEGylation is defined as the covalent attachment of poly(ethylene glycol) (PEG) chains to bioactive substances, such as nanoparticles, proteins, peptides or non-peptide molecules. This technology emerged gradually with progress in field of biologicals and polymer chemistry and was exploited to improve pharmaceutical applications of a wide range of therapeutics. Nowadays, PEGylation has become the leading approach for overcoming most of the limits of biologics and numbers of FDA approved PEGylated products like enzymes (bovine adenosine deaminase and urate oxidase), cytokines (interferon-α2a, interferon-α2b), granulocyte colony stimulating factors, hormones (epoetin-β), antibodies and their fragments and other organic molecules (pegvisomant, pegatinib) are on the market.

Application Fields
Bio-medical Industry
As an amphiphilic polymer, PEG can be soluble in water and most organic solvents, and has the characteristics of good biocompatibility, non-toxicity, and low immunogenicity. It can be excreted through the kidneys, so there will be no accumulation phenomenon in the body. In addition, PEG is easy to bind with proteins, nanocarriers and small molecule drugs,i.e., PEGylation, after the terminal hydroxyl group is activated, thus being widely applied into various biomedical areas, such as drug delivery, imaging diagnosis, pharmaceutical preparation and tissue engineering.

Chemical Synthesis
In recent years PEG aqueous solutions have been widely applied in many different kinds of reaction systems. Their low-toxicity, low volatility, and biodegradability represent important environmentally benign characteristics, which are particularly attractive when combined with their relatively low cost as a bulk commodity chemical. In addition, aqueous PEG solutions may often substitute for other expensive and toxic phase-transfer catalysts.

Source: https://peg.bocsci.com/resources/introduction-of-polyethylene-glycol-peg.html
Comments (0)
No login
gif
color_lens
Login or register to post your comment