Fungal spores and bacteria are among the bioaerosols carried in contaminated air, spreading easily with air currents. Exposure to such air can have adverse effects on human body, causing allergies, toxic reactions and infectious diseases. In indoor environments, several disinfection technologies are available to ensure excellent air quality for human health and comfort. Among the numerous technologies employed to remove microorganisms from indoor environments, the use of filters in air circulation units is considered to be the most efficient. High efficiency particulate air (HEPA) filter removes by trapping airborne microorganisms, but this presents a risk as microorganisms can remain viable on the filter and proliferate under ideal environmental conditions. They can become source of re...[ Read more ]

Fungal spores and bacteria are among the bioaerosols carried in contaminated air, spreading easily with air currents. Exposure to such air can have adverse effects on human body, causing allergies, toxic reactions and infectious diseases. In indoor environments, several disinfection technologies are available to ensure excellent air quality for human health and comfort. Among the numerous technologies employed to remove microorganisms from indoor environments, the use of filters in air circulation units is considered to be the most efficient. High efficiency particulate air (HEPA) filter removes by trapping airborne microorganisms, but this presents a risk as microorganisms can remain viable on the filter and proliferate under ideal environmental conditions. They can become source of recontamination and gaseous emissions. This can lead to filter degradation, lowering its efficiency and paving the way for microbial penetration. Thus, it becomes very crucial to develop particulate air filters with antimicrobial property. In this work, two novel antimicrobial coating material were developed based on iodine assembled in polymer systems and ionic liquids. Both coating possess multi-level antimicrobial property and are effective against bacteria, fungal spores, bacteria endospores, and bacteriophages. Aging studies at accelerated temperature conditions revealed that HEPA filters deposited with the antimicrobial coatings can maintain over 1 log reduction in spores and over 2 log reductions in bacteria and bacteriophages for a period of 24 months. Filtration studies carried out has shown that deposition of the coatings on HEPA filters does not alter the filtration properties of the filters. The antimicrobial filters fabricated from the coatings can effectively remove 97.532% of bacteria and 86.455% of mold from the indoor environment when deployed in air purifiers. The technology employed in the coating development is simple, safe, cost-effective and possess smart functions. Deposition of the coating system on HEPA filters or other filtration devices will not only impart antimicrobial property but improve filtration properties as well as prevent microbial viability, attachment, and accumulation on filter surface.