Assessing the Efficacy, Robustness and Safety of Spacecraft Surfaces Incorporating Pylote SAS Mineral Oxide Antimicrobial Technology

Spaceflights induce unique environmental conditions such as cosmic radiation, microgravity, and temperature fluctuations that alter microbial behavior and the human microbiome. These changes include enhanced virulence, increased biofilm formation, and elevated antimicrobial resistance, posing challenges to astronaut health. Microorganisms transferred from Earth to spacecraft can adapt to these conditions, leading to increased pathogenicity. Current antimicrobial measures, including surface disinfectants, can be hazardous and show limited long-term effectiveness against these adapted microorganisms, highlighting the need for novel solutions for microbial control in space environments. This study evaluated the antimicrobial efficiency of Pylote SAS inert mineral oxide microspheres incorporated into varnishes and resins under conditions in line with spaces use to provide a long-term solution for microbial control in spacecraft environments whatever the surfaces materials. The antimicrobial efficacy, robustness, and safety of samples, with and without Pylote technology, were tested using standardized methods. The antimicrobial activity was assessed according to ISO 22196, comparing Pylote-treated samples to controls against Escherichia coli, Staphylococcus epidermidis, and Bacillus subtilis, selected through the MATISS program to represent relevant microorganisms in space environments. The technology's robustness test was undertaken under simulated real-use conditions through 1,352 cleaning cycles using chlorhexidine-based wipes. Cytotoxicity was evaluated using ISO 10993-5 standard based on XTT assay regarding leachable substances. Results showed that Pylote-treated samples exhibited superior antimicrobial activity compared to untreated samples, with a log reduction of >2 against the selected strains. After 1,352 cleaning cycles, no bacterial growth was detected after the contact with the Pylote-treated surfaces, confirming the technology's sustainable antimicrobial effect. Cytotoxicity testing revealed no leachable substances at cytotoxic concentrations, ensuring safety for aerospace applications. These findings demonstrate the potential of Pylote’ mineral oxide microspheres to provide a innovative, safe, and efficient solution for microbial contamination control on numerous different surfaces, equipment and devices in space environments.