Microgravity

Germicidal Ultraviolet Light Biofilm Inhibition (GULBI) Experiment in Microgravity

By Keith Cowing

Press Release

November 5, 2025

Filed under Bacteria, Biofilm, bioreactor, Germicidal Ultraviolet Light Biofilm Inhibition (GULBI), ISS, microbiology, Microgravity, Pseudomonas aeruginosa, sace biology, space life science

Germicidal Ultraviolet Light Biofilm Inhibition (GULBI) Experiment in Microgravity — Germicidal UV light is emitted by an optical fiber running through the center of an agar plate. Researchers are testing whether microgravity changes the ability of the light to prevent growth of microbial communities known as biofilms. Credit: Arizona State University Larger image

The Germicidal Ultraviolet Light Biofilm Inhibition (GULBI) experiment was launched to the to the International Space Station National Laboratory on Northrop Grumman-23.

Biofilms form very easily in microgravity and can lead to equipment failures and human health risks. Biofilm in space is being studied with a new method involving germicidal ultraviolet light (UV-C)

The bacterial pathogen P. aeruginosa was be seeded into the BioCells on orbit and grown under different levels of UV light that is delivered via optical fibers into the bioreactors before samples are returned to Earth for analysis.

Individual components of hardware for the GULBI investigation, which examines how microgravity affects the ability of a type of ultraviolet (UV) light to prevent formation of large communities of microbes called biofilms. Credit: Arizona State University larger image

Astrobiology, space biology, microbiology, microgravity,

Keith Cowing

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻

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