An image of the programmable MOF-textile composite for eliminating biological and chemical threats. Image: Northwestern University.
An image of the programmable MOF-textile composite for eliminating biological and chemical threats. Image: Northwestern University.

A research team at Northwestern University has developed a versatile composite fabric that can deactivate biological threats, such as the novel coronavirus that causes COVID-19, and chemical threats, such agents used in chemical warfare. A material that is effective against both classes of threats is rare.

The composite fabric is also reusable: it can be restored to its original state after being exposed to threats with a simple bleach treatment. This promising fabric could be used in face masks and other protective clothing.

“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,” said Northwestern’s Omar Farha, an expert in metal-organic frameworks (MOFs), which form the basis for the technology. Farha, a professor of chemistry in the Weinberg College of Arts and Sciences, is a co-corresponding author of a paper on this work in the Journal of the American Chemical Society.

The MOF/fiber composite builds on an earlier study in which Farha’s team created a nanomaterial that deactivates toxic nerve agents. With some small manipulations, the researchers were also able to incorporate antiviral and antibacterial agents into the material.

According to Farha, MOFs are “sophisticated bath sponges”. The nano-sized materials are designed with a lot of holes that can capture gases, vapors and other agents, much like a sponge captures water. In the new composite fabric, the cavities of the MOFs contain catalysts that can deactivate toxic chemicals, viruses and bacteria. The porous nanomaterial can be easily coated on textile fibers.

The researchers found that the MOF/fiber composite exhibited rapid activity against SARS-CoV-2 and both Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus). Also, the active chlorine-loaded MOF/fiber composite rapidly degraded sulfur mustard gas and its chemical simulant (2-chloroethyl ethyl sulfide, CEES). The nanopores of the MOF material coated on the textile are also wide enough to allow sweat and water to escape.

The composite material is scalable, Farha added, as it only requires basic textile processing equipment currently used by industry. When incorporated into a face mask, the material should be able to work both ways: protecting the mask wearer from the virus in his or her vicinity, as well as protecting individuals who come into contact with an infected person wearing the mask.

In addition, the researchers were able to develop an understanding of the material’s active sites down to the atomic level. This allowed them and others to derive structure-property relationships that could lead to the creation of other MOF-based composites.

This story is adapted from material from Northwestern University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.