Integrated photothermal decontamination device for N95 respirators

Abstract

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) responsible for the COVID-19 global pandemic has infected over 25 million people worldwide and resulted in the death of millions. The COVID-19 pandemic has also resulted in a shortage of personal protective equipment (PPE) in many regions around the world, particularly in middle- and low-income countries. The shortages of PPE, such as N95 respirators, is something that will persist until an effective vaccine is made available. Thus, devices that while being easy to operate can also be rapidly deployed in health centers, and long-term residences without the need for major structural overhaul are instrumental to sustainably use N95 respirators. In this report, we present the design and validation of a decontamination device that combines UV-C & B irradiation with mild-temperature treatment. The device can decontaminate up to 20 masks in a cycle of < 30 min. The decontamination process did not damage or reduce the filtering capacity of the masks. Further, the efficacy of the device to eliminate microbes and viruses from the masks was also evaluated. The photothermal treatment of our device was capable of eradicating > 99.9999% of the bacteria and > 99.99% of the virus tested.

Riboflavin Surface Modification of Poly(vinyl chloride) for Light-Triggered Control of Bacterial Biofilm and Virus Inactivation

“…To further evaluate the ability of our modified plastic to eradicate microorganisms, a viral photoinactivation experiment was performed using a lentivirus surrogate model of SARS-CoV-2. − Lentivirus is a cost-effective and safe model for SARS-CoV-2 as they have a similar envelope and lipid bilayer surface features. For viral inactivation, the irradiance was identical to the previous experiments but the time was halved (29.2 J/cm 2 total dose).…”

Disinfection and decontamination in the context of SARS‐CoV‐2‐specific data

“…Although wavelengths of UV‐A and UV‐B have been considered as less effective, the utility of non‐UV‐C wavelengths remains controversial 95–97 . Combinations of UV wavelengths and temperature enhancements have also been studied 98 . There is also the potential to combine UV treatment with sensitizing agents for niche application 99 …”

“…[95][96][97] Combinations of UV wavelengths and temperature enhancements have also been studied. 98 There is also the potential to combine UV treatment with sensitizing agents for niche application. 99 The exploitation of UV-C for SARS-CoV-2 inactivation has been studied intensively.…”

Ultraviolet-C Irradiation, Heat, and Storage as Potential Methods of Inactivating SARS-CoV-2 and Bacterial Pathogens on Filtering Facepiece Respirators

“…Ultraviolet germicidal irradiation (UVGI, 250 to 280 nm) is a portion of the UV-C spectrum (200 to 280 nm) frequently generated using low-pressure mercury lamps emitting at 253.7 nm [21]. Although the dose (or fluence) required to inactivate bacteria and viruses has been studied over the years [21], the current COVID-19 pandemic has reignited the need to develop cost-effective procedures to decontaminate surfaces and materials using UV-C [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. In the case of SARS-CoV-2, UV-C doses ranging from 16.9 mJ/cm 2 in cell culture [41] to 1500 mJ/cm 2 on FFR [42] are reportedly required to fully inactivate virus replication.…”