Surface Inactivation of Human Coronavirus by MACOMA™ UVA-TiO2 Coupled Photocatalytic Disinfection System

Abstract

There is an immense healthcare challenge and financial pressure due to the COVID-19 pandemic caused by a newly identified human coronavirus, SARS-CoV-2. Effective COVID-19 prevention efforts in healthcare, home, and community settings highlight the need for rapid, efficient, and no-contact SARS-CoV-2 inactivation strategies. Here, we examined the photocatalytic and virucidal activity of the MACOMA™ TiO2 photocatalytic film activated by an UVA-LED-12V-367 nm (MA-717836-1) lamp against the HCoV-OC43, a member of the beta coronaviruses family, like SARS-CoV-2, using quantitative RT-qPCR and virus infectivity assays. The UVA radiation-responsive TiO2 film accelerated virus inactivation (decreased viral titer) compared to the uncoated glass surface when placed at a vertical distance of 1.2 feet (~14 inches) from virus samples for 10, 30, and 60 min. UVA-LED exposure for both 10 and 30 min effectively reduced the viral RNA copies and the infectious virus in samples on TiO2-coated surfaces compared to the control surfaces. Importantly, a 60 min exposure of samples on the TiO2 completely eliminated HCoV-OC43. These results confirmed that the MACOMA™ UVA/TiO2-based disinfection system provides a rapid and complete surface inactivation of tested human coronavirus in a human-safe manner and has great potential for limiting the virus spread in poorly ventilated as well as high-traffic public places.

Adsorption and Inactivation of SARS-CoV-2 on the Surface of Anatase TiO2(101)

“…UV (200–280 nm) irradiation is a potentially effective disinfection method that is widely used for disinfection of surfaces and is able to deactivate different types of viruses including SARS-CoV-2 . Under UV irradiation, RNA absorbs the UV photon which blocks the transcription via the formation of pyrimidine dimers, while absorption of UV radiation by amino acids disturbs the activity and structural function of the proteins . However, the disinfection mechanism of SARS-CoV-2 under UV irradiation is not clear and requires further investigation.…”

Implication of nanotechnology to reduce the environmental risks of waste associated with the COVID-19 pandemic

“…It was suggested that this model could be promising for various air conditioning systems to make free cabin from bacterial and viral infections. Recently Uppal et al 70 proposed TiO 2 photocatalytic coating for virucidal activity against HCoV-OC43 virus which is a member of beta coronavirus family just like SARS CoV-2 under the influence of UV irradiation. It was found that the TiO 2 -coated glass surface exhibited good antiviral response against the virus compared to uncoated glass using T-qPCR and virus infectivity tests.…”

Recent Advances on Metal Oxide Based Nano-Photocatalysts as Potential Antibacterial and Antiviral Agents

“…The photocatalytic disinfection was explained by observing the virion morphology using transmission electron microscopy (TEM) by detecting damaged viral RNA and proteins as shown in Figure 9a. These nano-photocatalysts are shown to be very promising antiviral coatings for protecting surfaces against the spread of viruses such as COVID-19 [73][74][75]. Recently Uppal et al [74] performed the study of a TiO 2 photocatalytic coating for virucidal activity against the HCoV-OC43 virus which is a member of the beta coronaviruses family just like SARS-CoV-2 under the influence of UV irradiation using T-qPCR and virus infectivity assays.…”

“…These nano-photocatalysts are shown to be very promising antiviral coatings for protecting surfaces against the spread of viruses such as COVID-19 [73][74][75]. Recently Uppal et al [74] performed the study of a TiO 2 photocatalytic coating for virucidal activity against the HCoV-OC43 virus which is a member of the beta coronaviruses family just like SARS-CoV-2 under the influence of UV irradiation using T-qPCR and virus infectivity assays. It was found that the glass surface coated with TiO 2 exhibited better antiviral response as compared to uncoated glass against the virus.…”

“…This is evidenced by the presence of virus (white spots in Figure 10d) in the digital image of active SARS-CoV-2 virus without Cu x O/TiO 2 photocatalysts while when the photocatalysis was conducted under visible light irradiation using a white fluorescence bulb, no virus was seen (Figure 10e [73]). It is evident that the TiO 2 coating could be a potential nanomaterial for limiting the virus spread in poorly ventilated as well as in high-traffic public places [28,74,77].…”