As declared by World Health Organization (WHO), presently the whole world is facing a pandemic and a global crisis caused by a novel virus that was discovered to be the cause of a large and rapidly spreading outbreak of respiratory disease, including potentially fatal pneumonia, in Wuhan, China (starting Jan. 9, 2020).
The virus was provisionally designated 2019-nCoV and later given the official name SARS-CoV-2, the disease caused by the virus was officially named Coronavirus Disease 2019 (COVID-19) by WHO.
The SARS-CoV-2 is an enveloped, positive-sense, single-stranded RNA virus. Coronaviruses are so named because of their characteristic solar corona (crown-like) appearance when observed under an electron microscope.
This appearance is produced by the peplomers of the surface (or spike; designated S) glycoprotein radiating from the virus lipidenvelope1. The SARS-CoV virion is spherical with an average diameter of 78 nm.
SARS-CoV-2 is a delicate but highly contagious virus capable of spreading primarily from person to person around the world. It also spreads when an infected person coughs or sneezed and a droplet landed on a surface or object, a person when touches that surface has the virus on it, then touches nose, mouth or eyes, could pick it up.
On a personal level, hygiene measures are recommended to prevent the spread of disease, especially in institutions where individuals are in contact with patients or contaminated fomites.
Washing hands with soap and water or with alcohol-based hand rubs are effective for interrupting virus transmission.
Although viruses don’t grow on any nonliving surfaces recent studies show coronaviruses can remain viable or infectious on metal, glass, wood, fabrics and plastic surfaces for several hours to days, irrespective of the surface looking dirty or clean.
Though the coronaviruses are relatively easy to destroy, using simple disinfectants like ethanol (62-71%), hydrogen peroxide (0.5%) or sodium hypochlorite (0.1%)2 by breaking the delicate envelope that surrounds the tiny microbe. However, it’s practically impossible to sanitize the surfaces all the time and it doesn’t guarantee that the surface won’t get contaminated again.
It’s a much wiser solution in such a scenario if the surface can repel the pathogens, making it nonstick and/or "sanitize by itself" by neutralizing the contaminated pathogens quickly, thus eliminating the possibilities of transfer of microorganism to the human body and its subsequent spreads.
Studies show that the spike glycoprotein of COVID-19 allows the virus to dock and bind to the ACE2 surface proteins of human epithelial cells in the respiratory tract thereby infecting these cells. Association of the COVID-19 spike glycoprotein with host ACE2 surface protein is a crucial step for infection.
Our research aim is to create surface coating with relatively low surface energy value which may repel the spike glycoprotein to anchor the surfaces of landing, also use of active chemicals that could inactivate the spike glycoprotein as well as viral nucleotides.
As we already have developed an anti-microbial coating solution virtually for all surfaces with an effective combination of nano-actives, having proven literature support as anti-virus too, we are pretty convinced about its performance as an antiviral too and this should resist the transmission of the virus from nonliving articles to living body cells by touch.
Literature survey shows that the nanoparticles (NPs) of various metals and metal oxides like Zinc Oxide nanoparticles (ZnONPs)3, Cuprous Oxide nanoparticles (CuONPs)4, Silver nanoparticles (AgNPs)5,6, Nanosized Copper (I) Iodide particles (CuINPs)7, Gold nanoparticles on Silica nanoparticles (Au-SiO2NPs)8and also some Quaternary ammonium cations commonly called QUATs9 are very promising to inactivate the virus and are well proven.
The product we have developed, NANOVA HYGIENE+TM as an antimicrobial coating for surfaces like fabrics, plastics, metals and concretes contains the cocktails of non-migratory QUATs and positively charged AgNPs as bioactive nanoparticles and dispersing this into binder polymers. This anti-microbial coating also shows extremely low surface energy value (>20 mN/m)10 and behaves as an omniphobic surface by repelling water and oil together.
Contact angels were>130o and >50o when measured against water and hexadecane as probes10, respectively.
This coating has proven test reports11 on protection against bacteria pathogens up to 99.9% as per the global standard JIS Z2801.
The coated surfaces also have evidence to work effectively against fungi12 and algae pathogens.
From available published data in literature, we can safely opine that NANOVA HYGIENE+TMwould be a potential coating candidate to repel and inactivate virus on the surface, hence could be a potential material to address the present problem of COVID-19 spread through surface touch.
The plausible ways of functioning of the doped nano active materials against COVID-19 viruses would be as follow:
- As AgNPs has been reported to inhibit the replication of virus nucleotides, the main mechanism of its being virulent. It binds to electron donor groups such as Sulfur, Oxygen, and Nitrogen commonly found in enzymes within the microbe. This causes the enzymes to be denatured thus effectively incapacitating the energy source of the cell and the microbe will quickly die;
- The cationic silver (Ag+)or QUATs might work to inactivate the SARS-CoV-2 by interacting with its surface (spike) protein S based on its charge like it works in HIV, Hepatitis viruses, etc.5,6
As NANOVA HYGIENE+ TM omniphobic antimicrobial coating shows complete disablement of various pathogenic bacteria already and further on the basis of available scientific supports, we are in the opinion that the present formula should work against a broad spectrum of viruses as well.
Initial anti-viral test of NANOVA HYGIENE+ TM has been performed using MS2 Bacteriophage (Poliovirus), a small non-enveloped RNA virus of the family Leviviridae. The results show with anti-viral efficacy13 of 99.9% in just 2 hours of contact with the surface as per global standard AATCC 100-2012.
Further, an anti-viral test is in the process to establish its efficacy on inactivation of COVID-19 on different surfaces to stop the secondary spread from various surfaces to living cells through touch. Once validated, it has numerous applications virtually for all surfaces like fabric (mask, gloves, doctor coats, curtains, bed sheet), metal (lifts, doors handle, nobs, railings, public transport), wood (furniture, floors and partition panels), concrete (hospitals, clinics and isolation wards), plastics (switches, kitchen and home appliances) and potentially could save many lives.
1. Chen, Y., Liu, Q., Guo, D. Emerging Coronaviruses: Genome structure, replication, and pathogenesis. J Med Virol, 2020.
2. Kampf, G., Todt, D., Pfaender, S., Steinmann, E. Persistence of Coronaviruses on inanimate surfaces and its inactivation with biocidal agents. J Hosp Infect, 2020.
3. Tavakoli A, Ataei-Pirkooh A, Mm Sadeghi G, Bokharaei-Salim F, Sahrapour P, Kiani SJ, Polyethylene glycol-coated zinc oxide nanoparticle: an efficient nano weapon to fight against herpes simplex virus type 1, Nanomedicine, 2018;13(21), 2675–90.
5. Elechiguerra, J.L., Burt, J.L., Morones, J.R., Camacho-Bragado, A., Gao, X., Lara, H.H., Yacaman, M.J., Interaction of silver nanoparticles with HIV-1.J Nanobiotechnology. 2005, 3(6), 6.
6. Galdiero, S., Falanga, A., Vitiello, M., Cantisani, M., Marra, V., Galdiero, M., Silver nanoparticles as potential antiviral agents, Molecules. 2011, 16(10), 8894-918.
7. Fujimori, Y., Sato, T., Hayata, T., Nagao, T., Nakayama, M., Nakayama T., Sugamata, R., Kazuo Suzuki, K., Novel Antiviral Characteristics of Nanosized Copper(I) Iodide Particles Showing Inactivation Activity against 2009 Pandemic H1N1 Influenza Virus, Applied and Environmental Microbiology, 2011, 951–955.
8. Lysenko, V., Lozovski, V., Lokshyn, M., Gomeniuk, Y., Dorovskih, A., Rusinchuk, N., Pankivska, Y., Povnitsa, O., Zagorodnya, S., Tertykh, V., Nanoparticles as antiviral agents against adenoviruses, Advances in Natural Sciences: Nanoscience and Nanotechnology, 2018, 9, 025021.
9. Torkelson, A., da Silva A.K., Love1, D.C., Kim, J.Y., Alper, J.P., Coox, B.,1, Dahm, J.,
Kozodoy, P., Maboudian, R., Nelson, K.L., Investigation of quaternary ammonium silane-coated sand ﬁlter for the removal of bacteria and viruses from drinking water, J. Applied Microbiology, 2012, 113, 1196-1207.
10. Nova Surface Care Centre, Report No: NSCC/SER/06 Dated: 24/08/2019.
11. Biotech Testing Services, Certificate No: 1900577/3 Dated: 26/06/2019.
12. The Bombay Textile Research Association, Certificate No: BTL/TR/1700912/MWO/3/2017 Dated: 27/06/2017.