A Comparative Study of the Antiviral Properties of Thermally Sprayed Coatings against Human Coronavirus HCoV-229E

Abstract

For decades, novel viral strains of respiratory tract infections have caused human pandemics and initiated widespread illnesses. The recent coronavirus disease 2019 (COVID-19) outbreak caused by the SARS-CoV-2 virus has raised an urgent need to develop novel antiviral coatings as one of the potential solutions to mitigate the transmission of viral pathogens. Titanium dioxide is considered an excellent candidate for viral disinfection under light irradiation, with the potential to be activated under visible light for indoor applications. This research assessed the antiviral performance of thermally sprayed TiO2 coatings under UVA and ambient light. We also report the antiviral performance of TiO2 composites with other oxides, such as Cu2O and Al2O3, produced by suspension plasma spray, atmospheric plasma spray, and suspension high-velocity oxygen fuel techniques. To evaluate the antiviral performance of the above coatings in a containment level-2 laboratory, a human common cold coronavirus, HCoV-229E, was initially used as a relevant surrogate for SARS-CoV-2. Coatings were also analyzed using SEM and XRD and were classified based on their surface roughness, porosity, and phase composition. Collectively, the thermally sprayed coatings showed comparable or slightly better antiviral activity compared to copper. The most significant level of activity observed was approximately 20% to 50% higher than that of a pure copper plate.

The Influence of the Q-SUN and UV-B Irradiation on the Antiviral Properties of the PP Films Covered with the Coatings Based on ZnO Nanoparticles and TiO2

“…Analyzing the influence of one-day UV-B irradiation on layers and their antiviral properties, it should be mentioned that the Zn, ZnT2 and ZnT3 coatings showed moderate antiviral activity, confirming that UV-B irradiation activated the nanoparticles. It is worth mentioning that the longer UV-B irradiation (48 h) deteriorated the antiviral effectiveness of all analyzed coatings, clearly showing that UV-B irradiation should not exceed 24 h. Alebrahim et al [2] also analyzed antiviral coatings containing TiO 2 , Cu 2 O, TiO 2 -Cu 2 O and TiO 2 -Al 2 O 3 nanoparticles. They confirmed that TiO 2 -Cu 2 O and TiO 2 -Al 2 O 3 -based coatings had higher activity than coatings with TiO 2 and Cu 2 O.…”

“…Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) is an agent that causes coronavirus disease . Despite the available treatments against SARS-CoV-2 and vaccination, there are still about 767 million cases of daily worldwide infections, including over 6.9 million deaths, due to the COVID-19 pandemic [1,2]. Additionally, RNA viruses, which have a high mutation rate, like SARS-CoV-2, increase the risk of multiresistant variant development with more virulence characteristics [1].…”

“…Additionally, RNA viruses, which have a high mutation rate, like SARS-CoV-2, increase the risk of multiresistant variant development with more virulence characteristics [1]. This virus, which is highly communicable, is mainly transmitted though respiratory droplets and aerosols during human-to-human interactions [3] or indirectly through physical contact, usually via the hands after being deposited on surfaces, such as packaging [2]. The spread of virus particles has demonstrated the necessity to develop novel materials with antimicrobial properties to prevent the infection of current viruses and yet-unknown variants that could appear in the future [1][2][3][4].…”

“…This virus, which is highly communicable, is mainly transmitted though respiratory droplets and aerosols during human-to-human interactions [3] or indirectly through physical contact, usually via the hands after being deposited on surfaces, such as packaging [2]. The spread of virus particles has demonstrated the necessity to develop novel materials with antimicrobial properties to prevent the infection of current viruses and yet-unknown variants that could appear in the future [1][2][3][4]. Antiviral surface material treatments may influence virus particles through a reduction in their number or can directly avoid these hazards [4].…”

“…The antimicrobial properties of various metals nanoparticles, such as ZnO, TiO 2 , copper and silver nanoparticles, have been extensively studied and documented [2,[5][6][7].…”