Control of Bioaerosols in Indoor Environment by Filter Coated with Nanosilicate Platelet Supported Silver Nanohybrid (AgNPs/NSP)

Abstract

Currently silver nanoparticles (AgNP)-modified filter are widely used to inactivate airborne microbes in indoor environment. However, AgNP is extremely small and thus will penetrate cells membranes to cause cytotoxicity. AgNPs/NSP has been proven to be less cytotoxic to human body. In this study, it was the first time that AgNPs/NSP was used to develop a new antimicrobial air filter with low cytotoxicity. The AgNPs/NSP filter was made by dip-coating of filter with AgNPs/NSP and acrylic resin solution and three different amount of silver on filter were obtained including 12.6, 31.5 and 63 ppm. The filtration efficiency and the antimicrobial activity of AgNP/NSP filter were evaluated by bioaerosols including Escherichia coli and Candida famata in testing chamber and HVAC simulation system under 30% and 70% relative humidity (RH). The results showed that filtration efficiency of AgNPs/NSP-modified filter increased by about 13 to 20% compared to unmodified filter for E. coli but remained almost the same for C. famata. The antimicrobial efficiency of AgNPs/NSP modified filter of 63 ppm was 95.1% for E. coli at RH of 30%. In addition, 91% of antimicrobial efficiency for C. famata was found at RH of 70%. On the other hand, the antimicrobial efficiency of yeast for AgNPs/NSP-modified filter was 97.8% and 86.4% for RH of 30% and 70% respectively when yeast just started to contact with filter in HVAC system. The results suggest that AgNP/NSP-modified air filter can effectively inactivate microorganisms retained on. Therefore, emission of bioaerosols from air filter can be avoided in order to improve the air cleaning technology in indoor environment.

Face Masks in the New COVID-19 Normal: Materials, Testing, and Perspectives

“…Nanoparticles of silver (Ag) [ 178 – 180 ], silver compounds (Ag + ) [ 181 ], titanium dioxide (TiO 2 ) [ 182 , 183 ], zinc oxide (ZnO) [ 184 – 186 ], and aluminum and aluminum oxide (Al 2 O 3 ) [ 187 ] have been incorporated to various filters for antimicrobial properties. A synergistic antimicrobial performance is also revealed via their combination with other biocidal agents, such as carbon nanotubes [ 178 , 180 , 181 ]. Apart from antimicrobial air filters, multifunctional air filters, which simultaneously remove PM, microorganisms, and volatile organic compounds (VOCs), have drawn increasing research attention recently [ 188 , 189 ].…”

Radiant catalytic ionization improves the microbiological status of rodent facilities without affecting the prooxidative status of mice

“…8,9 Filters can be pre-treated with antibacterial agents (e.g. tea tree oil, 10 silver nanoparticles 11 or flavonoids 12 ) to inactivate microorganisms. Another method for protecting filter surfaces from microorganisms involves combining HEPA filters with photocatalytic systems.…”

Preparation and Characteristic of Antibacterial Facemasks with Chinese Herbal Microcapsules

“…Bioaerosols generated from airborne particles of biological origin include fungi, bacteria, viruses, and fragments of the foregoing or their metabolic products (e.g., endotoxins, mycotoxins) (Chow et al, 2015;Walser et al, 2015;Chen et al, 2016;Zhang et al, 2016;Lal et al, 2017). Environmental health studies have indicated that constant exposure to bioaerosols containing high concentrations of bacteria can lead to respiratory diseases including allergies, infections, and other adverse health effect (Bünger et al, 2007;Lu et al, 2016;Mirhoseini et al, 2016).…”