{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:30:24Z","timestamp":1760146224822,"version":"build-2065373602"},"reference-count":54,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2024,10,21]],"date-time":"2024-10-21T00:00:00Z","timestamp":1729468800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Federal Ministry of Economics and Technology","award":["KK5191602LU1"],"award-info":[{"award-number":["KK5191602LU1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>The contamination of surfaces by antibiotic-resistant pathogens presents an escalating challenge, especially on touchscreens in public settings such as hospitals, airports, and means of transport. Traditional chemical cleaning agents are often ineffective and leave behind harmful residues. Thus, the application of optical radiation is gaining relevance as a rapid, effective, and environmentally friendly disinfection method. This study examines the contamination of publicly accessible touchscreens and the efficacy of an irradiation approach for the radiation disinfection of microorganisms on quartz surfaces with UVC LEDs. In this setup, the LED radiation is laterally coupled into a quartz plate that serves as cover glass of a simplified touchscreen model. The process allows for the irradiation of microorganisms on the surface, without the user being exposed to hazardous radiation. To assess the efficacy of the disinfection process, a range of bacteria, mostly ESKAPE surrogates, such as Staphylococcus carnosus, Acinetobacter kookii, Escherichia coli, Enterococcus mundtii, and additionally Micrococcus luteus, were spread over a quartz plate with a homebuilt nebulization system. After operating the side-mounted LEDs for 30 s, a reduction in all bacteria except M. luteus by more than three orders of magnitude was observed. In the case of M. luteus, a significant reduction was achieved after 60 s (p &lt; 0.05). This result demonstrates the potential of side-mounted UVC LEDs for rapid disinfection of touchscreens between two users and thus for reducing the spread of pathogens without irradiating humans.<\/jats:p>","DOI":"10.3390\/microorganisms12102099","type":"journal-article","created":{"date-parts":[[2024,10,21]],"date-time":"2024-10-21T06:35:00Z","timestamp":1729492500000},"page":"2099","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Decontamination of Fused-Silica Surfaces by UVC Irradiation as Potential Application on Touchscreens"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4614-6043","authenticated-orcid":false,"given":"Ben","family":"Sicks","sequence":"first","affiliation":[{"name":"Institute of Medical Engineering and Mechatronics, Ulm University of Applied Sciences, 89075 Ulm, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Oksana","family":"Gurow","sequence":"additional","affiliation":[{"name":"Institute of Medical Engineering and Mechatronics, Ulm University of Applied Sciences, 89075 Ulm, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Florian","family":"Sommerfeld","sequence":"additional","affiliation":[{"name":"Institute of Medical Engineering and Mechatronics, Ulm University of Applied Sciences, 89075 Ulm, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4859-2864","authenticated-orcid":false,"given":"Martin","family":"Hessling","sequence":"additional","affiliation":[{"name":"Institute of Medical Engineering and Mechatronics, Ulm University of Applied Sciences, 89075 Ulm, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,21]]},"reference":[{"key":"ref_1","first-page":"Doc30","article-title":"Review of microbial touchscreen contamination for the determination of reasonable ultraviolet disinfection doses","volume":"16","author":"Hessling","year":"2021","journal-title":"GMS Hyg. Infect. Control"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1016\/S0195-6701(07)60015-2","article-title":"Environmental contamination makes an important contribution to hospital infection","volume":"65","author":"Boyce","year":"2007","journal-title":"J. Hosp. Infect."},{"key":"ref_3","first-page":"Doc10","article-title":"The role of surface disinfection in infection prevention","volume":"8","author":"Gebel","year":"2013","journal-title":"GMS Hyg. Infect. Control"},{"key":"ref_4","unstructured":"Kommission f\u00fcr Krankenhaushygiene und Infektionspr\u00e4vention (KRINKO) beim Robert Koch-Institut (2012). Hygienema\u00dfnahmen bei Infektionen oder Besiedlung mit Multiresistenten Gramnegativen St\u00e4bchen: Empfehlung der Kommission f\u00fcr Krankenhaushygiene und Infektionspr\u00e4vention (KRINKO) beim Robert Koch-Institut (RKI), Springer."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"226","DOI":"10.1016\/j.ajic.2004.04.197","article-title":"The benefits of surface disinfection","volume":"32","author":"Rutala","year":"2004","journal-title":"Am. J. Infect. Control"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"e00181-19","DOI":"10.1128\/CMR.00181-19","article-title":"Antimicrobial Resistance in ESKAPE Pathogens","volume":"33","author":"Forde","year":"2020","journal-title":"Clin. Microbiol. Rev."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Venkateswaran, P., Vasudevan, S., David, H., Shaktivel, A., Shanmugam, K., Neelakantan, P., and Solomon, A.P. (2023). Revisiting ESKAPE Pathogens: Virulence, resistance, and combating strategies focusing on quorum sensing. Front. Cell. Infect. Microbiol., 13.","DOI":"10.3389\/fcimb.2023.1159798"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"e368","DOI":"10.1016\/S1473-3099(18)30296-2","article-title":"Quantifying drivers of antibiotic resistance in humans: A systematic review","volume":"18","author":"Chatterjee","year":"2018","journal-title":"Lancet Infect. Dis."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"837","DOI":"10.1016\/j.chom.2024.05.015","article-title":"Antibiotic resistance: A key microbial survival mechanism that threatens public health","volume":"32","author":"Abbas","year":"2024","journal-title":"Cell Host Microbe"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"697","DOI":"10.1016\/j.arcmed.2005.06.009","article-title":"Resistance to antibiotics: Are we in the post-antibiotic era?","volume":"36","author":"Alanis","year":"2005","journal-title":"Arch. Med. Res."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1082","DOI":"10.1126\/science.aax3879","article-title":"The evolution of antibiotic resistance","volume":"365","author":"MacLean","year":"2019","journal-title":"Science"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Lin, J., Nishino, K., Roberts, M.C., Tolmasky, M., Aminov, R.I., and Zhang, L. (2015). Mechanisms of antibiotic resistance. Front. Microbiol., 6.","DOI":"10.3389\/fmicb.2015.00034"},{"key":"ref_13","first-page":"3","article-title":"Bedeutung und H\u00e4ufigkeit von Toleranzen gegen\u00fcber bioziden Wirkstoffen in Antiseptika und Desinfektionsmitteln","volume":"39","author":"Kampf","year":"2020","journal-title":"Epidemiol. Bull."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"304","DOI":"10.1016\/j.scitotenv.2012.03.043","article-title":"Effect of coupled UV-A and UV-C LEDs on both microbiological and chemical pollution of urban wastewaters","volume":"426","author":"Chevremont","year":"2012","journal-title":"Sci. Total Environ."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Li, Y., Chen, X., Wang, Y., and Zhang, Y. Effects of environmental factors, measurement and modeling for germicidal efficiency of in-duct ultraviolet germicidal irradiation system. Energy Built Environ., 2024. in press.","DOI":"10.1016\/j.enbenv.2024.03.006"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"e61","DOI":"10.1016\/j.ajic.2015.06.019","article-title":"A new UV-LED device for automatic disinfection of stethoscope membranes","volume":"43","author":"Messina","year":"2015","journal-title":"Am. J. Infect. Control"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1049\/htl2.12032","article-title":"Hospital surface disinfection using ultraviolet germicidal irradiation technology: A review","volume":"9","author":"Scott","year":"2022","journal-title":"Healthc. Technol. Lett."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"487","DOI":"10.1016\/j.jmii.2017.08.017","article-title":"Effectiveness of an ultraviolet-C disinfection system for reduction of healthcare-associated pathogens","volume":"52","author":"Yang","year":"2019","journal-title":"J. Microbiol. Immunol. Infect."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"586","DOI":"10.1016\/j.ajic.2013.12.013","article-title":"Implementation and impact of ultraviolet environmental disinfection in an acute care setting","volume":"42","author":"Haas","year":"2014","journal-title":"Am. J. Infect. Control"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"102161","DOI":"10.1016\/j.pdpdt.2020.102161","article-title":"Evaluation of a portable Ultraviolet C (UV-C) device for hospital surface decontamination","volume":"33","author":"Santos","year":"2021","journal-title":"Photodiagnosis Photodyn. Ther."},{"key":"ref_21","unstructured":"(1982). Strahlungsphysik im Optischen Bereich und Lichttechnik: Gr\u00f6\u00dfen, Formelzeichen und Einheiten der Strahlungsphysik, 1982\u201303 (Standard No. DIN 5031-1:1982-03)."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Kowalski, W. (2009). Ultraviolet Germicidal Irradiation Handbook: UVGI for Air and Surface Disinfection, Springer.","DOI":"10.1007\/978-3-642-01999-9"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1007\/s00203-012-0847-5","article-title":"Wavelength dependence of biological damage induced by UV radiation on bacteria","volume":"195","author":"Santos","year":"2013","journal-title":"Arch. Microbiol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1842","DOI":"10.1039\/c8pp00182k","article-title":"Solar UV damage to cellular DNA: From mechanisms to biological effects","volume":"17","author":"Mullenders","year":"2018","journal-title":"Photochem. Photobiol. Sci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"280","DOI":"10.1016\/j.foodres.2017.04.009","article-title":"Bactericidal effect of 266 to 279 nm wavelength UVC-LEDs for inactivation of Gram positive and Gram negative foodborne pathogenic bacteria and yeasts","volume":"97","author":"Kim","year":"2017","journal-title":"Food Res. Int."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"4779","DOI":"10.1093\/nar\/gkg675","article-title":"Cell cycle arrest and apoptosis provoked by UV radiation-induced DNA damage are transcriptionally highly divergent responses","volume":"31","author":"Gentile","year":"2003","journal-title":"Nucleic Acids Res."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Gray, N.F. (2014). Ultraviolet Disinfection. Microbiology of Waterborne Diseases, Elsevier.","DOI":"10.1016\/B978-0-12-415846-7.00034-2"},{"key":"#cr-split#-ref_28.1","unstructured":"European Parliament, Council of the European Union (2024, September 26). Directive 2006\/25\/EC of the European Parliament and of the Council of 5 April 2006 on the Minimum Health and Safety Requirements Regarding the Exposure of Workers to Risks Arising from Physical Agents (Artificial Optical Radiation) (19th Individual Directive Within the Meaning of Article 16"},{"key":"#cr-split#-ref_28.2","unstructured":"(1) of Directive 89\/391\/EEC), 2006 (2006\/25\/EC). Available online: https:\/\/eur-lex.europa.eu\/legal-content\/EN\/ALL\/?uri=CELEX%3A32006L0025."},{"key":"ref_29","unstructured":"(2022). TLVs\u00ae and BEIs\u00ae: Based on the Documentation of the Threshold Limit Values for Chemical Substances and Physical Agents & Biological Exposure Indices, ACGIH."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"211","DOI":"10.1086\/669092","article-title":"Microbial assessment of high-, medium-, and low-touch hospital room surfaces","volume":"34","author":"Huslage","year":"2013","journal-title":"Infect. Control Hosp. Epidemiol."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Hammon, M., Kunz, B., Dinzl, V., Kammerer, F.J., Schwab, S.A., Bogdan, C., Uder, M., and Schlechtweg, P.M. (2014). Practicability of hygienic wrapping of touchscreen operated mobile devices in a clinical setting. PLoS ONE, 9.","DOI":"10.1371\/journal.pone.0106445"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"321","DOI":"10.3390\/opt4020023","article-title":"Disinfection of Transparent Screens by Side-Coupled UVA LED Radiation","volume":"4","author":"Sicks","year":"2023","journal-title":"Optics"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"981","DOI":"10.1109\/LPT.2024.3422903","article-title":"Future Disinfection of Touch Screens by Far-UVC-LEDs?\u2014A Feasibility Study","volume":"36","author":"Sicks","year":"2024","journal-title":"IEEE Photon. Technol. Lett."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Bertolotti, M., Sibilia, C., and Guzman, A.M. (2017). Evanescent Waves. Evanescent Waves in Optics, Springer International Publishing.","DOI":"10.1007\/978-3-319-61261-4"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1111\/jmi.12070","article-title":"A \u2018pocket guide\u2019 to total internal reflection fluorescence","volume":"252","author":"Tynan","year":"2013","journal-title":"J. Microsc."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Gierke, A.-M., and Hessling, M. (2022). Investigation on Potential ESKAPE Surrogates for 222 and 254 nm Irradiation Experiments. Front. Microbiol., 13.","DOI":"10.3389\/fmicb.2022.942708"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1016\/j.ijfoodmicro.2004.11.038","article-title":"GInaFiT, a freeware tool to assess non-log-linear microbial survivor curves","volume":"102","author":"Geeraerd","year":"2005","journal-title":"Int. J. Food Microbiol."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Exarhos, G.J., Gruzdev, V.E., Menapace, J.A., Ristau, D., and Soileau, M.J. (2016). Metrology of fused silica. Laser-Induced Damage in Optical Materials 2016. SPIE Laser Damage, Boulder, CO, USA, Sunday 25 September 2016, SPIE.","DOI":"10.1117\/12.2242487"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1016\/j.watres.2014.11.028","article-title":"Action spectra for validation of pathogen disinfection in medium-pressure ultraviolet (UV) systems","volume":"70","author":"Beck","year":"2015","journal-title":"Water Res."},{"key":"ref_40","unstructured":"Pirnie, M., Linden, K.G., and Malley, J.P. (2024, July 18). Ultraviolet Disinfection Guidance Manual for the Final Long Term 2 enhanced Surface Water Treatment Rule, Washington, DC, Available online: https:\/\/www.epa.gov\/system\/files\/documents\/2022-10\/ultraviolet-disinfection-guidance-manual-2006.pdf."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"602","DOI":"10.1093\/infdis\/27.6.602","article-title":"The Thermal Death Point in Relation to Time of Typical Thermophilic Organisms","volume":"27","author":"Bigelow","year":"1920","journal-title":"J. Infect. Dis."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1016\/S0168-1605(00)00362-7","article-title":"Structural model requirements to describe microbial inactivation during a mild heat treatment","volume":"59","author":"Geeraerd","year":"2000","journal-title":"Int. J. Food Microbiol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1111\/j.1365-2672.1977.tb00665.x","article-title":"Tailing of survival curves of bacterial spores","volume":"42","author":"Cerf","year":"1977","journal-title":"J. Appl. Bacteriol."},{"key":"ref_44","unstructured":"(1995). Essentials of the Microbiology of Foods: A Textbook for Advanced Studies, Wiley."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1099\/00207713-36-1-8","article-title":"Enterococcus mundtii sp. nov","volume":"36","author":"Collins","year":"1986","journal-title":"Int. J. Syst. Bacteriol."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1099\/00207713-52-2-629","article-title":"Emended descriptions of the genus Micrococcus, Micrococcus luteus (Cohn 1872) and Micrococcus lylae (Kloos et al. 1974)","volume":"52","author":"Wieser","year":"2002","journal-title":"Int. J. Syst. Evol. Microbiol."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"4402","DOI":"10.1099\/ijs.0.047969-0","article-title":"Acinetobacter kookii sp. nov., isolated from soil","volume":"63","author":"Choi","year":"2013","journal-title":"Int. J. Syst. Evol. Microbiol."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1099\/00207713-32-2-153","article-title":"Description of a New Species of the Genus Staphylococcus: Staphylococcus carnosus","volume":"32","author":"Schleifer","year":"1982","journal-title":"Int. J. Syst. Bacteriol."},{"key":"ref_49","first-page":"485","article-title":"Evolution in Pseudomonas fluorescens","volume":"120","author":"Champion","year":"1980","journal-title":"J. Gen. Microbiol."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"510","DOI":"10.1128\/MMBR.00047-05","article-title":"Biology of Pseudomonas stutzeri","volume":"70","author":"Lalucat","year":"2006","journal-title":"Microbiol. Mol. Biol. Rev."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1099\/00222615-1-2-195","article-title":"Pseudomonas stutzeri in pathological material","volume":"1","author":"Lapage","year":"1968","journal-title":"J. Med. Microbiol."},{"key":"ref_52","doi-asserted-by":"crossref","unstructured":"Koscova, J., Hurnikova, Z., and Pistl, J. (2018). Degree of Bacterial Contamination of Mobile Phone and Computer Keyboard Surfaces and Efficacy of Disinfection with Chlorhexidine Digluconate and Triclosan to Its Reduction. Int. J. Environ. Res. Public Health, 15.","DOI":"10.3390\/ijerph15102238"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"678","DOI":"10.1086\/598243","article-title":"Monitoring the effectiveness of hospital cleaning practices by use of an adenosine triphosphate bioluminescence assay","volume":"30","author":"Boyce","year":"2009","journal-title":"Infect. Control Hosp. Epidemiol."}],"container-title":["Microorganisms"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2607\/12\/10\/2099\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:17:12Z","timestamp":1760113032000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2607\/12\/10\/2099"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,10,21]]},"references-count":54,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2024,10]]}},"alternative-id":["microorganisms12102099"],"URL":"https:\/\/doi.org\/10.3390\/microorganisms12102099","relation":{},"ISSN":["2076-2607"],"issn-type":[{"type":"electronic","value":"2076-2607"}],"subject":[],"published":{"date-parts":[[2024,10,21]]}}}