After the outbreak of COVID-19, there has been a huge shortage of face masks worldwide — particularly, the N95 ones worn by health care workers. Although these coverings provide the highest level of protection currently available, they have limitations.
Now, researchers reporting in ACS Nano have developed a membrane that can be attached to a regular N95 mask and replaced when needed. The filter has a smaller pore size than normal N95 masks, potentially blocking more virus particles.
N95 masks filter about 85% of particles smaller than 300 nm. SARS-CoV-2 (the coronavirus that causes COVID-19) is in the size range of 65-125 nm, so some virus fragments could slip through these coverings.
Because of shortages, many health care workers have had to wear the same N95 mask repeatedly, even though they are intended for a single use. To help overcome these problems, Muhammad Mustafa Hussain and colleagues wanted to develop a membrane that more efficiently filters particles the size of SARS-CoV-2 and could be replaced on an N95 mask after every use.