Chemical-physical criticality and toxicological potential of lipid nanomaterials contained in a COVID-19 mRNA vaccine


  • Gabriele Segalla Multichem R&D



COVID-19 mRNA vaccine, LNP, lipid nanoparticles, nanomaterials, nanoforms, electrolytes, reactive oxygen species, aggregate, agglomerate, flocculate


The medicinal preparation called Comirnaty by Pfizer-BioNTech is an aqueous dispersion of lipid nanomaterials, intended to constitute, after thawing and dilution, the finished product for intramuscular injection. In the present study, we examine some evident chemical-physical criticalities of the preparation, regarding the manifest instability of its qualitative-quantitative composition, as well as its consequent toxicological potential, in this case related to the possible formation of ROS (reactive oxygen species), after intramuscular inoculation, in different biological sites, such as, potentially, kidneys, liver, heart, brain, etc., causing dysfunctions and alterations thereof.

Of particular concern is the presence in the formulation of the two functional excipients, ALC-0315 and ALC-0159, never used before in a medicinal product, nor registered in the European Pharmacopoeia, nor in the European C&L inventory. The current Safety Data Sheets of the manufacturer are omissive and non-compliant, especially with regard to the provisions of current European regulations on the registration, evaluation, authorization and restriction of nanomaterials.

The presence of electrolytes in the preparation and the subsequent dilution phase after thawing and before inoculation raise well-founded concerns about the precarious stability of the resulting suspension and the Polydispersity index of the nanomaterials contained in it, factors that can be hypothesized as the root causes of numerous post-vaccination adverse effects recorded at statistical-epidemiological level. Further immediate studies and verifications are recommended, taking into consideration, if necessary and for purely precautionary purposes, the immediate suspension of vaccinations with the Pfizer-BioNTech Comirnaty preparation.

Author Biography

Gabriele Segalla, Multichem R&D

Segalla, PhD, is head of the MULTICHEM research and development laboratory and has created a portfolio of innovative formulations and products from cosmetics to household formulations; he is the holder of various patents in the field of organic chemistry and plant derivatives, some of which are visible on the website; the most recent are those relating to a new molecule, used as a lipophilic derivative of niacin (vitamin B3) in cosmetic and personal care products.


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How to Cite

Segalla, G. (2023). Chemical-physical criticality and toxicological potential of lipid nanomaterials contained in a COVID-19 mRNA vaccine. International Journal of Vaccine Theory, Practice, and Research, 3(1), 787–817.