{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,17]],"date-time":"2026-10-17T02:57:35Z","timestamp":1792205855650,"version":"4.4.0"},"reference-count":39,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,5,8]],"date-time":"2023-05-08T00:00:00Z","timestamp":1683504000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004955","name":"Austrian Research Promotion Agency","doi-asserted-by":"publisher","award":["#888037"],"award-info":[{"award-number":["#888037"]}],"id":[{"id":"10.13039\/501100004955","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The highly contagious SARS-CoV-2 virus is primarily transmitted through respiratory droplets, aerosols, and contaminated surfaces. In addition to antiviral drugs, the decontamination of surfaces and personal protective equipment (PPE) is crucial to mitigate the spread of infection. Conventional approaches, including ultraviolet radiation, vaporized hydrogen peroxide, heat and liquid chemicals, can damage materials or lack comprehensive, effective disinfection. Consequently, alternative material-compatible and sustainable methods, such as nanomaterial coatings, are needed. Therefore, the antiviral activity of two novel zinc-oxide nanoparticles (ZnO-NP) against SARS-CoV-2 was investigated in vitro. Each nanoparticle was produced by applying highly efficient \u201cgreen\u201d synthesis techniques, which are free of fossil derivatives and use nitrate, chlorate and sulfonate salts as starting materials and whey as chelating agents. The two \u201cgreen\u201d nanomaterials differ in size distribution, with ZnO-NP-45 consisting of particles ranging from 30 nm to 60 nm and ZnO-NP-76 from 60 nm to 92 nm. Human lung epithelial cells (Calu-3) were infected with SARS-CoV-2, pre-treated in suspensions with increasing ZnO-NP concentrations up to 20 mg\/mL. Both \u201cgreen\u201d materials were compared to commercially available ZnO-NP as a reference. While all three materials were active against both virus variants at concentrations of 10\u201320 mg\/mL, ZnO-NP-45 was found to be more active than ZnO-NP-76 and the reference material, resulting in the inactivation of the Delta and Omicron SARS-CoV-2 variants by a factor of more than 106. This effect could be due to its greater total reactive surface, as evidenced by transmission electron microscopy and dynamic light scattering. Higher variations in virus inactivation were found for the latter two nanomaterials, ZnO-NP-76 and ZnO-NP-ref, which putatively may be due to secondary infections upon incomplete inactivation inside infected cells caused by insufficient NP loading of the virions. Taken together, inactivation with 20 mg\/mL ZnO-NP-45 seems to have the greatest effect on both SARS-CoV-2 variants tested. Prospective ZnO-NP applications include an antiviral coating of filters or PPE to enhance user protection.<\/jats:p>","DOI":"10.3390\/ijms24098425","type":"journal-article","created":{"date-parts":[[2023,5,9]],"date-time":"2023-05-09T02:28:08Z","timestamp":1683599288000},"page":"8425","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":50,"title":["Antiviral Activity of Zinc Oxide Nanoparticles against SARS-CoV-2"],"prefix":"10.3390","volume":"24","author":[{"given":"Stella","family":"Wolfgruber","sequence":"first","affiliation":[{"name":"Diagnostic and Research Center for Molecular Biomedicine, Institute of Pathology, Medical University of Graz, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia","family":"Rieger","sequence":"additional","affiliation":[{"name":"Diagnostic and Research Center for Molecular Biomedicine, Institute of Pathology, Medical University of Graz, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olavo","family":"Cardozo","sequence":"additional","affiliation":[{"name":"PHORNANO Holding GmbH, Kleinengersdorferstrasse 24, 2100 Korneuburg, Austria"},{"name":"Post-Graduate Program on Electrical Engineering, Federal University of Pernambuco, Cidade Universitaria, Recife 50670-901, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9662-4739","authenticated-orcid":false,"given":"Benjamin","family":"Punz","sequence":"additional","affiliation":[{"name":"Department of Biosciences and Medical Biology, Paris Lodron University of Salzburg, 5020 Salzburg, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5416-085X","authenticated-orcid":false,"given":"Martin","family":"Himly","sequence":"additional","affiliation":[{"name":"Department of Biosciences and Medical Biology, Paris Lodron University of Salzburg, 5020 Salzburg, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Stingl","sequence":"additional","affiliation":[{"name":"PHORNANO Holding GmbH, Kleinengersdorferstrasse 24, 2100 Korneuburg, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8800-6500","authenticated-orcid":false,"given":"Patricia M. A.","family":"Farias","sequence":"additional","affiliation":[{"name":"PHORNANO Holding GmbH, Kleinengersdorferstrasse 24, 2100 Korneuburg, Austria"},{"name":"Department of Biophysics and Radiobiology, Post-Graduate Program on Material Sciences, Federal University of Pernambuco, Cidade Universitaria, Recife 50670-901, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1957-4066","authenticated-orcid":false,"given":"Peter M.","family":"Abuja","sequence":"additional","affiliation":[{"name":"Diagnostic and Research Center for Molecular Biomedicine, Institute of Pathology, Medical University of Graz, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5299-7218","authenticated-orcid":false,"given":"Kurt","family":"Zatloukal","sequence":"additional","affiliation":[{"name":"Diagnostic and Research Center for Molecular Biomedicine, Institute of Pathology, Medical University of Graz, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1100","DOI":"10.1016\/j.it.2020.10.004","article-title":"Mechanisms of SARS-CoV-2 Transmission and Pathogenesis","volume":"41","author":"Harrison","year":"2020","journal-title":"Trends Immunol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1186\/s12985-020-01418-7","article-title":"The Effect of Temperature on Persistence of SARS-CoV-2 on Common Surfaces","volume":"17","author":"Riddell","year":"2020","journal-title":"Virol. 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