A replaceable, more efficient filter for N95 masks

Since the outbreak of COVID-19, there's been a worldwide shortage of face masks -- 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.