Inactivation of Aspergillus niger conidia applying antifungal photocatalytic paints: a kinetic study

Inactivation of Aspergillus niger conidia applying antifungal photocatalytic paints: a kinetic study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Inactivation of Aspergillus niger conidia applying antifungal photocatalytic paints: a kinetic study Silvia Mercedes Zacarias, Delfina Martin, Valentina Wandel Petersen, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6298369/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Airborne fungal contamination in indoor environments is a growing concern, highlighting the need for innovative microbial control strategies. Developing novel photocatalytic materials for fungal control requires understanding the mechanisms and kinetics of photocatalytic inactivation. This study investigates the inactivation kinetics of Aspergillus niger conidia using a batch reactor and three TiO₂-based paints: rutile (non-photocatalytic), anatase (UV-active), and carbon-doped anatase (UV/Vis-active). Experiments were conducted at two relative humidity (RH) levels (50% and 70–80%) and three radiation fluxes (100%, 56%, and 18%). An empirical kinetic model was developed to describe the dependence of inactivation on radiation flux (power function) and RH (logistic model). Results showed a photocatalytic effect under UV light for photocatalytic paints, while photochemical effects dominated with non-photocatalytic paint. At 50% RH, logarithmic reductions per treatment day were 0.77 and 0.54 for anatase and rutile paints, respectively. At 70–80% RH, photocatalytic inactivation increased significantly, whereas rutile paint remained unchanged. The proposed kinetic model effectively captured the influence of radiation flux and RH, showing strong correlation with experimental data. airborne fungi decontamination air disinfection microorganisms photocatalytic paints titanium dioxide Full Text Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6298369","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":470016072,"identity":"c4c16b21-5c85-4200-8497-ffa4bf34cc0b","order_by":0,"name":"Silvia Mercedes 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Developing novel photocatalytic materials for fungal control requires understanding the mechanisms and kinetics of photocatalytic inactivation. This study investigates the inactivation kinetics of Aspergillus niger conidia using a batch reactor and three TiO₂-based paints: rutile (non-photocatalytic), anatase (UV-active), and carbon-doped anatase (UV/Vis-active). Experiments were conducted at two relative humidity (RH) levels (50% and 70\u0026ndash;80%) and three radiation fluxes (100%, 56%, and 18%). An empirical kinetic model was developed to describe the dependence of inactivation on radiation flux (power function) and RH (logistic model). Results showed a photocatalytic effect under UV light for photocatalytic paints, while photochemical effects dominated with non-photocatalytic paint. At 50% RH, logarithmic reductions per treatment day were 0.77 and 0.54 for anatase and rutile paints, respectively. 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