Mechanisms of instantaneous inactivation of SARS-CoV-2 by silicon nitride bioceramic

Abstract

The hydrolytic processes occurring at the surface of silicon nitride (Si 3 N 4 ) bioceramic have been indicated as a powerful pathway to instantaneous inactivation of SARS-CoV-2 virus. However, the virus inactivation mechanisms promoted by Si 3 N 4 remain yet to be elucidated. In this study, we provide evidence of the instantaneous damage incurred on the SARS-CoV-2 virus upon contact with Si 3 N 4 . We also emphasize the safety characteristics of Si 3 N 4 for mammalian cells. Contact between the virions and micrometric Si 3 N 4 particles immediately targeted a variety of viral molecules by inducing post-translational oxidative modifications of S-containing amino acids, nitration of the tyrosine residue in the spike receptor binding domain, and oxidation of RNA purines to form formamidopyrimidine. This structural damage in turn led to a reshuffling of the protein secondary structure. These clear fingerprints of viral structure modifications were linked to inhibition of viral functionality and infectivity. This study validates the notion that Si 3 N 4 bioceramic is a safe and effective antiviral compound; and a primary antiviral candidate to replace the toxic and allergenic compounds presently used in contact with the human body and in long-term environmental sanitation.

Raman Fingerprints of the SARS-CoV-2 Delta Variant and Mechanisms of Its Instantaneous Inactivation by Silicon Nitride Bioceramics

“… 12 , 13 The combination of the TCID 50 assay, RT-PCR, and fluorescence spectroscopy results provides unequivocal evidence for the occurrence of SARS-CoV-2 Delta variant inactivation by Si 3 N 4 bioceramic powder. In our previous work on the antipathogenic properties of Si 3 N 4 , 12 , 13 , 15 − 19 , 64 we have suggested that ammonia eluted by hydrolytic reactions taking place at the Si 3 N 4 surface in an aqueous solution plays a fundamental role in the lysis of pathogens and inactivation of viral strains including the JPN/TY/WK-521 variant. In order to substantiate the mechanisms of viral inactivation, we applied Raman spectroscopy to screen the structural details of inactivated virions at the molecular scale.…”

“…The differences in the molecular structure and symmetry between the SARS-CoV-2 Japanese isolate and the two sub-types of the Alpha variant were stunningly bold. In two additional studies, 12 , 13 we have proposed the exploitation of the surface chemistry of silicon nitride bioceramics in an aqueous environment as an instantaneous and powerful antiviral effect against SARS-CoV-2. Unlike other solid-state antiviral agents, 14 Si 3 N 4 is a compound fully biocompatible toward eukaryotic cells while effectively counteracting pathogens.…”

“…Since ssRNA virions have no capacity to resist ammonia attack to their RNA and viral proteins, 19 , 20 they become instantaneously inactivated by the presence of a few volume percent of micrometer-sized Si 3 N 4 particles in aqueous solution. 12 , 13 , 15 …”

Nitric Oxide Delivering Surfaces: An Overview of Functionalization Strategies and Efficiency Progress

“…[60] Several studies have demonstrated the ability of these silicon nitride-based materials to promote osteogenesis, [61,62] to lyse bacteria such as S. epidermidis [58] or Porphyromonas gingivalis [63] and to inactivate viruses such as SARS-CoV-2. [64] Therefore, this type of structure could be an interesting strategy to limit the risks of bacterial infections related to the implantation of osteoarticular prosthesis. However, the production by these materials of reactive nitrogen/oxygen species, such as peroxynitrite ions, can represent a significant risk of nitrosative and oxidative stress induction.…”

A Novel Antipathogenic Agent for Nonwoven Fabric

“…It has proven to be effective against a range of gram-positive and -negative bacteria [ 23 – 34 ] along with some fungi [ 35 , 36 ], and its effectivity appears to be at least equivalent to other antimicrobial agents. Recent publications demonstrated its ability to rapidly inactivate viruses including SARS-CoV-2 [ 37 – 40 ]. In this study, it was hypothesized that non-woven fabric embedded with Si 3 N 4 would not only trap viral droplets and particles, but also render them harmless.…”