UNIVERSITY OF ALABAMA IN HUNTSVILLE — Researchers at the University of Alabama in Huntsville have demonstrated that plasma jets can effectively sanitize fabric in space without using water, offering a potential solution for long-duration space missions. The experiment, led by professor Gabe Xu, treated cotton fabric samples contaminated with Staphylococcus caprae—a common skin bacterium also found aboard the International Space Station—using a pencil-thin, bright-purple jet of charged gas generated by a cellphone-sized device.
The plasma treatment killed bacteria more effectively than current International Space Station cleaning methods, such as dry vacuuming and chemical surface wipes. When applied to fabric, the plasma produced highly reactive oxygen and nitrogen species that penetrated fibers and ruptured bacterial cell membranes through oxidative stress. Treatments lasting from 30 seconds to five minutes caused no noticeable damage to the fabric, suggesting the method could be used repeatedly without degrading clothing or soft goods. “It is not going to remove the coffee stains from anyone's T-shirt, but it will remove the stuff that will make you sick,” Xu said. “We think that it's probably not any worse than just normal wear and tear.”
Conventional laundry is impractical in space due to limited water supplies, and many Earth-based disinfectants like Lysol pose risks in enclosed habitats because lingering chemical fumes can endanger crew health. Astronauts currently wear clothing until it becomes too soiled, then discard it as waste that burns up during atmospheric reentry. Future missions to the moon or Mars will lack regular resupply, making sustainable “space laundry” essential.
Xu emphasized the broader implications for shared surfaces in spacecraft. “You have a couch that six astronauts, or however many, are sitting on day in, day out. How do you keep that thing sanitized so that they don't spread germs to each other?” he said. The plasma sanitization technique requires only electricity and a working gas, eliminating the need for water-intensive systems.
The research team, which included NASA microbiologist and planetary protection engineer Chelsi Cassilly, is now expanding tests to other microbial species known to thrive in human environments and aboard spacecraft.