Functionalized non-woven surfaces for combating the spread of the COVID-19 pandemic

Abstract

The worldwide outbreak of SARS-CoV-2 infection has necessitated mandatory use of face masks, personal protective equipment and intake of a healthy diet for immunity boosting. As per WHO's recommendation, continuous use of masks has been proven effective in decreasing the SARS-CoV-2 infection rate. The present study reports on the bacterial filtration efficacy (BFE) of a novel 4-ply functionalized non-woven face mask. We synthesized a polypropylene-based fabric with inner layers of melt-blown fine fibres coated with polylactic acid and immune-boosting herbal phytochemicals. Experimental studies on the synthesized face mask demonstrated a BFE of greater than 99% against Staphylococcus aureus (a bacterium species frequently found in mammalian respiratory tract). A thorough computational analysis using LibDock algorithm demonstrated an effective docking performance of herbal phytochemicals against harmful virus structures. More importantly, the face mask also showed sufficient and stable breathability as per regulatory standards. A breathing resistance of 30 Pa at an aerosol flow rate of 30 l h^-1 was reported under standard temperature and pressure conditions, indicating a high potential for real-world applications.

Keywords: 4-ply functionalized non-woven face mask; LibDock; SARS-CoV-2; algorithm; herbal phytochemicals; personal protective equipment.

Figure 1.

Marketed product image of Aushadatara face mask.

Figure 2.

FE-SEM micrographs of the face mask sample. (a) Washed sample of spun-bonded outermost layer of face mask, (b) unwashed sample of outermost layer of face mask, (c) washed sample of melt-blown filter media, (d) unwashed sample of melt-blown filter media, (e) washed sample of PLA spray-coated layer and (f) unwashed sample of PLA spray-coated layer.

Figure 3.

Fibre diameter distribution of (a) washed spray-coated layers, (b) washed melt-blown layers, (c) washed outer layers, (d) unwashed melt-blown layer, (e) unwashed outer layer and (f) unwashed spray-coated layer at a standard room temperature of 25 ± 2°C.

Figure 4.

Heat map analysis of major constituent chemicals in the herbal-extract-based formulation (A) against airborne viruses (SARS2, severe respiratory syndrome coronavirus 2; H7N9, drug-resistant influenza A; DEGV, Dengue virus; INF, influenza; HNTV, hantavirus; HCV, hepatitis C virus; EBV, Ebola virus; HSV, herpes simplex virus).

Figure 5.

The heat map analysis of major constituent chemicals in the herbal-extract-based formulation (B) against airborne viruses (INF, influenza; SARS2, severe acute respiratory syndrome coronavirus 2; HPS, hantavirus; HCV, hepatitis C virus; DENV, Dengue virus; HSV, herpes simplex virus; ZIKV, Zika virus; EVD, Ebola virus disease).

Figure 6.

Contact angle analysis of the outer layer of mask material. (a) Outer layer in face mask and (b) inner side of top layer of face mask.