Researchers seek cost-effective way to decontaminate PPE

Since April, investigators have studied how to disinfect coronavirus-exposed N95 masks so healthcare workers can reuse them safely.

The shortage of personal protective equipment (PPE), specifically N95 masks, remains an issue globally. With the fall flu season compounding the current coronavirus pandemic, U.S. hospitals' supply will be further strained.  A UW Medicine urologist and a radiology fellow are looking for a work-around.

For the last six months, Drs. Thomas Lendvay and Tanner Clark have worked with Dr. James Chen, a Seattle neurosurgeon, examining the viability of disinfecting N95 masks so healthcare workers can reuse them safely. Infectious diseases specialist Jaya Sahni of Seattle Children’s Research Institute also became a collaborator after his lab pivoted from studying HIV to COVID-19 after the pandemic emerged this spring.

Industry-standard masks, including the N95, are designed as single-use devices. It is very difficult to sanitize them without destroying them or rendering them toxic to the wearer. Currently a few commercially available products and methods effectively disinfect PPE, but most require expensive equipment that many hospitals cannot afford or manage.

Lendvay, a professor in the urology department, University of Washington School of Medicine, is studying whether methylene blue, combined with light, could disinfect PPE quickly, inexpensively, and without causing PPE to become ineffective or unsafe. Methylene blue is a readily available chemical, even in developing countries. It is used in the sterilization of blood plasma for transfusion and is also a topical method of sanitization once it encounters light or sunlight.

If this solution is viable, it would significantly increase the volume of available protective gear worldwide. Lendvay started this work with a $100,000 Amazon grant and funding from an anonymous donor in Seattle.

His investigation is now part of the DeMaND study (Development of Methods for Mask and N95 Decontamination), which involves researchers from the Centers for Disease Control and Prevention, the World Health Organization, and from 12 institutions including the University of Washington School of Medicine.

“We are testing whether methylene blue plus bright light can kill virus on N95 masks and PPE so that we can provide healthcare workers with a better and safer solution for reusing their gear,” said Lendvay. “Because methylene blue and light are widely available and inexpensive, we believe that this solution can scale to nations around the globe with fewer resources and where support for healthcare workers is scarce.”

Results from Lendvay’s work and that of the other universities are expected to be published this fall. 

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Tags:PPE (personal protective equipment)masks

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