Of all approved COVID-19 vaccines in the market, the vaccines developed by BioNTech/Pfizer and Moderna has received widespread attention from all over the world, which represent a new class of vaccine products: they are composed of messenger ribonucleic acid (mRNA) strands encapsulated in lipid nanoparticles (LNPs).
mRNA vaccines are new types of vaccines that have aroused great interest. The main challenge for their applications is how to ensure their effective delivery. This is because the physicochemical properties of mRNA (such as negative charge and hydrophilicity) hinder the passive diffusion of mRNA vaccines through the plasma membrane. Moreover, mRNA vaccines are also susceptible to nuclease degradation. For example, free mRNA will quickly decompose in the body, greatly reducing its effectiveness.
It is necessary to use advanced technology to avoid this situation, thereby improving the stability of the vaccine, and this is where the lipid nanoparticles(LNPs) come into play. Currently, the approved mRNA COVID-19 vaccines (Table 1) are utilizing LNP technology. This illustrates the successes achieved with this type of nanoparticle to stabilize mRNA and successfully deliver it into cells. To be specific, LNPs have two advantages as an mRNA vaccine vector. On the one hand, LNPs defend mRNA from degradation by enzymes from the endosome. The characteristic guarantees high encapsulation efficiency. On the other hand, LNPs have good biocompatibility through a series of biological processes to deliver mRNAs for expression.
|Category||Pfizer-BioNTech mRNA vaccine||Moderna mRNA vaccine|
|mRNA dose||30 µg||100 µg|
|Route of administration||intramuscular||intramuscular|
|Lipid nanoparticle components||ALC-0315 = (4-hydroxybutyl) azanediyl)bis (hexane-6,1-diyl)bis(2-hexyldecanoate)
ALC-0159 = 2-[(polyethylene glycol)-2000]-N,N ditetradecylacetamide
|SM-102=(heptadecan-9-yl 8-((2-hydroxyethyl) (6-oxo-6-(undecyloxy) hexyl) amino) octanoate}
PEG2000-DMG = 1-monomethoxypolyethyleneglycol-2,3-dimyristylglycerol with polyethylene glycol (2000)
1,2-Distearoyl-sn-glycero-3 phosphocholine (DSPC)
|Buffer||Potassium dihydrogen phosphate
Disodium hydrogen phosphate dihydrate
|Other excipients||Potassium chloride
Water for injection
Water for injection
Table 1:Approved mRNA COVID-19 vaccines
The LNPs in mRNA COVID-19 vaccines consist of four main components: a neutral phospholipid, cholesterol, a polyethylene-glycol (PEG)-lipid, and an ionizable cationic lipid, among them, PEG can enhance the stability and lifespan of LNPs. According to public information, PEG has never appeared in any other vaccines in the world. This will be another new application of PEG in the field of medicine.
The structure of lipid nanoparticle vaccine carrier: mRNA organized in reverse lipid micelles in the nanoparticles (A); mRNA embedded between lipid bilayers (B)
Huateng Pharma is a dynamic science company dedicated to PEG derivatives and intermediates. We are capable of supplying small to large quantities of a rich selection of PEG derivatives and fine chemicals to serve bio-technology and pharmaceutical companies and research organizations worldwide. We can supply the following products used in COVID-19 vaccines.
|Category||Product Name||CAS NO.||Link|
|PEG||mPEG-N,N-Ditetradecylacetamide, ALC-0159||1849616-42-7||View Detailes>|
Polyethylene glycol [PEG] 2000 dimyristoyl glycerol [DMG]
Methoxypoly(ethylene glycol) 2000
Methoxypoly (ethylene glycol) propylamine
Methoxypoly(ethylene glycol) carboxymethyl 2000