1. Vacuum ultraviolet radiation from gaseous plasma for destruction of water contaminantsMark Zver, Rok Zaplotnik, Miran Mozetič, Alenka Vesel, Arijana Filipić, David Dobnik, Belisa Alcantara Marinho, Gregor Primc, 2025, original scientific article Abstract: Innovative technological solutions are needed for water decontamination to combat the diverse pollutants present in water systems, as no single optimal decontamination technique is appropriate for all circumstances. Vacuum-ultraviolet (V-UV) radiation is a source of energetic photons that break molecular bonds, producing a plethora of chemically reactive agents, most notably OH● radicals, which can cause the degradation of harmful pollutants. Low-pressure gaseous plasma is a good source of V-UV radiation; however, its application to liquid water poses challenges. We constructed an inductively coupled radiofrequency plasma to produce high-intensity V-UV radiation, which was applied to contaminated water via a V-UV-transparent window. Plasma was sustained in hydrogen, as it produces the highest V-UV intensity among all gases at selected discharge parameters. Bacteriophage MS2 was used as an indicator of microbial decontamination efficiency. Reactive oxygen and nitrogen species were measured at various treatment setups to quantify their effect on MS2 inactivation and elucidate the primary inactivation factors. At optimal conditions, the concentration of active virus dropped by 9 log10 PFU/mL in 60 s. The optimal experimental setup was then used to treat bacteria E. coli, S. aureus, antibiotic tetracycline, and synthetic dye methylene blue as representatives of other types of pollutants, all of which were effectively removed/degraded within 10 min of treatment. A comparison of energy efficiency (EEO) to other disinfection setups was made for bacteriophage inactivation. With a low EEO value, we showcase the potential of this technique for further work in this field.
Keywords: water treatment, radical
Published in DiRROS: 07.02.2025; Views: 918; Downloads: 434
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2. Antiviral respiratory masks with plasma-functionalized polypropylene textiles for optimal adsorption of antiviral substanceMark Zver, David Dobnik, Rok Zaplotnik, Miran Mozetič, Alenka Vesel, Arijana Filipić, Polona Kogovšek, Katja Fric, Alja Štern, Gregor Primc, 2024, original scientific article Abstract: During the COVID-19 pandemic, face masks were the first line of defense against the spread of infection. However, infectious viruses may remain on medical textiles, potentially serving as an additional source of infection. Due to their chemical inertness, many textiles cannot be enhanced with antiviral functionalities. Through treatment with low-pressure gaseous plasma, we have activated the surface of a medical-grade melt-blown, non-woven polypropylene textile so that it can absorb sodium dodecyl sulfate, an antimicrobial surfactant. Within two hours of contact time, the functionalized textile has been able to inactivate over 7 log10 PFU mL−1 of bacteriophage phi6, a surrogate of enveloped viruses such as SARS-CoV-2, and it has retained its antiviral properties for over 100 days. The functionalized material has not disrupted facial mask filtration efficiency or breathability. In addition, the in vitro biocompatibility testing in accordance with ISO 10993-5 for testing of medical devices has demonstrated that the selected formulation causes no adverse effects on the mouse fibroblast cell line L-929. With the treatment processes that have been completed within seconds, the method seems to have great potential to produce antiviral textiles against future outbreaks.
Keywords: surgical face masks, plasma functionalization, antiviral materials, virus filtration, breathability
Published in DiRROS: 07.10.2024; Views: 1169; Downloads: 846
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