Researchers have developed a special type of cloth face masks that kill up to 99.9999% of bacteria and viruses within 60 minutes of daylight exposure. Many people have become accustomed to wearing face masks. However, bacteria and viruses may stick to the mask and could be transferred elsewhere when the mask wearer touches or removes it. Face masks made up of various cloth materials can filter nanoscale aerosol particles released by a cough or sneeze and help reduce the spread of diseases.
Researchers have now developed a new cotton fabric that would release reactive oxygen species when exposed to daylight which kills the microbes while still being washable, reusable, and safe. The antimicrobial fabrics were made by attaching positively charged chains of 2-diethylamino ethyl chloride to ordinary cotton. The modified cotton was then dyed using a negatively charged photosensitizer. The researchers used rose Bengal as the photosensitizer. The mask killed 99.9999% of bacteria added to the fabric within 60 minutes of exposure to daylight. It inactivated T7 bacteriophage (a virus considered more resistant to ROS than some coronaviruses) within 30 minutes. Testing also revealed that the material could be washed at least 10 times and constantly exposed to daylight for at least 7 days making it reusable.
Ref link: https://www.sciencedaily.com/releases/2020/11/201111144407.htm