Northwestern University scientists have developed a new composite that’s capable of neutralizing both biological and chemical threats.
According to the team led by Northwestern professor Omar Farha, their programmable crystalline sponge-textile composite has so far proven effective against the COVID-19 virus, and chemical threats such as those used in chemical warfare.
Achieving a feat like this against both classes of threats is extremely rare and thus commendable.
According to Farha, the material is also reusable; it can be restored to its original state after the fabric has been exposed to threats by a simple bleach treatment.
This makes it a promising candidate for use in face masks and other protective clothing (PPE).
“Having a bifunctional material that has the ability to deactivate both chemical and biological toxic agents is crucial since the complexity to integrate multiple materials to do the job is high,” intones Farha, who is an expert in metal-organic frameworks (MOFs) which happens to be the basis of this new technology.
The MOF/fiber composite builds on an earlier study in which Farha’s team created a nanomaterial that deactivates toxic nerve agents.
In the current study, Farha and his colleagues banked on small manipulations to incorporate antiviral and antibacterial agents into the material.
Calling them ‘sophisticated bath sponges,’ Farha says these nano-sized materials are designed with a lot of holes that can capture gases, vapors and other agents the way a sponge captures water.
In Northwestern’s new composite fabric, the cavities of the MOFs have catalysts that can deactivate toxic chemicals, viruses and bacteria.
Moreover, the porous nanomaterial can be easily coated on textile fibers and are wide enough to allow sweat and water to escape.
When tested, the scientists found that their MOF/fiber composite exhibited rapid activity against SARS-CoV-2 and both gram-negative bacteria (E. coli) and gram-positive bacteria (S. aureus).
The active chlorine-loaded MOF/fiber composite also rapidly degraded sulfur mustard gas and its chemical simulant (2-chloroethyl ethyl sulfide, CEES).
if incorporated into a facemask, the material should be able to work both ways, says Farha: protecting the mask wearer from virus in his or her vicinity as well as protecting individuals who come into contact with an infected person wearing the mask.
Image and content: Angus Mordant-Bloomberg/Northwestern University