Researchers from the Faculty of Science, University of Peradeniya have been working hard ever since the COVID-19 pandemic commenced in Sri Lanka, about an year ago, by obtaining special permits from our police department. The researchers wanted to use our knowledge to combat this pandemic by contributing to its control. As such, they have developed an antimicrobial pigment to be used in paints to destroy viruses, bacterial, fungi and other harmful microorganisms. This was done using the sludge accumulated at the LTL Galvanizers Pvt Ltd. The LTL is now working on mass production of this pigment as a means of protecting surfaces from SARS CoV-2 attachment. At the same time, they wanted to develop a unique face mask with three layers from environmentally friendly cotton but to have aerosol particles containing SARS CoV-2 virus reflection in the uppermost layer, electrostatic and mechanical retention of the virus if by chance it passes through the upper layer and reaches the middle layer and to kill it by five different mechanisms.

To explain briefly the actions of the three layers:

The upper layer is made of cotton nano-technologically modified to have water repellency (superhydrophobic nature as it does by the lotus leaf). This means that if any aerosol particle containing the virus reaches the upper layer the particle is repels away and thrown out. This property also ensures cleanliness of the surface due to its non-wetting nature (The lotus leaf and swan's feathers are also very clean due to the same reason). Therefore, the mask is an advanced version of a surgical mask since any blood fallen on it is also repelled without letting go through.

The middle layer is also cotton but it is made by blocking the pores of the cotton cloth using microparticles just the size of the pores to ensure no particle penetration through it but to have free passage for molecules in air to ensure good breathability. The particles used have a positively charged surface so that they attract the negatively charged SARS CoV-2 viral envelope and bind electrostatically on their surface. The middle layer surface also contains star-shaped nanoparticles with sharp nanoblades capable of cutting the virus's spike proteins as the way you cut them using scissors. This is a unique characteristic since microbes cannot develop any resistance for this physical action of disruption. Therefore, the nanoparticles are capable of destroying not only the present variants of SARS CoV-2 but any future mutations and hybrid versions since all of them have these spike proteins which can be cut to pieces by our nanoblades. There are four other mechanisms by which these nanoparticles can destroy the virus but this physical action is the dominant one.

As said, the uppermost layer reflects the aerosol particles without allowing them to pass through. By any chance if they pass through and reach the middle layer, they are retained on it by two mechanisms and destroyed by five mechanisms. Therefore, these two layers of the mask ensure that the wearer does not get the virus. The virus killing efficiency was measured at our Virology Unit of the Microbiology Department of the Faculty of Medicine using a similar coronavirus called SRV and found that at half the concentration used the nanoparticles completely killed all the viruses giving Zero RSV Antigen Cell Viability. The materials were also tested for various bacteria and found that it kills all the bacteria types that we have studied. Therefore, the researchers are confident that this middle layer does not allow any viral or bacterial particle to pass through.

The innermost face contact layer is made of water-loving (hydrophilic) cotton for moisture absorption from the perspiration and to allow for easy evaporation in order to give maximum comfort to the wearer. There is no such advanced face mask so far developed anywhere in the world and hence it should have a high market potential.