Table 1.

Excipients of COVID-19 vaccine and their function.

Excipient	mRNA BNT162b2 Pfizer	mRNA-1273 Moderna	Janssen
Active	Nucleoside-modified mRNA encoding the viral spike glycoprotein of SAR-CoV-2	Nucleoside-modified mRNA encoding the viral spike glycoprotein of SAR-CoV-2	Recombinant, replication-incompetent Ad26 vector, encoding a stabilized variant of the SARS-CoV-2 spike (S) protein
Lipid nanoparticles: stability and transport of mRNA PEGylated lipids	2-[(Polyethylene glycol)-2000]-N,N-ditetradecylacetamide (ALC-0159), 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), ((4hydroxybutyl)azanediyl)bis (hexane-6,1-diyl)bis(2-hexyldecanoate) (ALC-0315), cholesterol	1,2-dimyristoyl-rac-glycero-3-methoxypolyethylene glycol-2000 (PEG2000 DMG), 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), lipid SM-102 (patented ionizable lipid), cholesterol
Buffer: stability of lipid nanoparticles/radical oxidation inhibition	Potassium dihydrogen phosphate/disodium phosphate dihydrate	Tromethamol/tromethamol hydrochloride, acetic acid/sodium acetate trihydrate
Other stabilizers: ionic strength, surfactant, metal-ion chelates	Potassium chloride, sodium chloride		Polysorbate 80, 2-hydroxypropyl-β-cyclodextrin, citric acid monohydrate, trisodium citrate dihydrate, sodium chloride, ethanol
Thermostabilization	Sucrose	Sucrose