Thursday, November 19, 2020

New Cloth Face Masks can be Disinfected by the Sun!

 Posted by Julia Munoz

In the current era of COVID-19, many people have turned to cloth face coverings. While this is good, viruses and bacteria that are stuck to the mask can be transferred off the mask when the mask is taken off. An article from ScienceDaily, discusses how ACS Applied Materials and Interfaces has developed a new cotton mask that kills 99.9999% of bacteria and viruses after only 60 minutes of daylight exposure.


Credit: Adapted from ACS Applied Materials and Interfaces 2020,
DOI:10.1021/acsami.Oc15540

Most face masks, which are made of various cloth materials, filter out nanoscale aerosol particles. These are usually released when someone coughs or sneezes. Wearing masks prevents these particles from being spread between peoples because it blocks their transmission. However, the bacteria and virus on the mask still remain contagious.  Peixin Tang, Gang Sun, Nitin Nitin and colleagues have been working on a new cotton fabric that would be able to release reactive oxygen when it was exposed to daylight, thus killing microbes attached to the cloth, while still being washable, reusable, and safe to wear.

ACS Appl. Mater. Interfaces 2020, 12, 44, 4944249451

Publication Date:October 22, 2020 https://doi.org/10.1021/acsami.0c15540 

The group made their antimicrobial masks by attaching positively charged chains of 2-diethylaminoethyl chloride to regular cotton. Next, they dyed the modified cotton in a solution of negatively charged photosensitizer. This attaches to the DEAE chains by strong electrostatic interactions. Testing showed that the mask could be handwashed at least 10 times and constantly exposed to daylight for 7 days before losing its antimicrobial defense. 





1 comment:

  1. Good title. Good graphics. The chemistry would not be that accessible to many, but it does make the point that chemistry is involved. Given the interest in Covid that we all must have, this is very timely and could attract interest, although it does not seem to have been picked up by general interest media besides Science Daily. Your summary in your own words is clear and effective.

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