NASA has achieved a breakthrough in its extraterrestrial sample storage cleanrooms by utilising InnovaPrep's dry electret sampler with N95-like filters, overcoming previous materials compatibility issues.
This sampler is proven to be effective in preventing contamination, unlike liquid and agar-based samplers.
"In combination with the tested and validated Bobcat monitoring system, this programme now offers NASA a safer, more efficient, and comprehensive cleanroom monitoring solution, ensuring the protection of precious samples from bioaerosols that traditional particle counters cannot guarantee," InnovaPrep stated.
Why electret sampling?
In a report, NASA wrote about "Insights from routine microbiological monitoring of air in astromaterials curation cleanrooms", talking about their experience using the electret filter to collect airborne biological particles.
In April 2022, the Administration began routinely collecting air samples in seven of the nine curation cleanrooms at Johnson Space Center, which included the OSIRIS-REx ISO 5 equivalent and the Meteorite ISO 7 equivalent.
Electret is a term used to to describe a media that is electrostatically charged, and it is this characteristic that is different to conventional samplers that use liquid media or petri dish agar media.
"This dry sample collection method allows us to meet materials requirements for all the curation labs and reduces the risk of inadvertently introducing contamination as part of our monitoring effort," the report stated.
This method also allows for preservation of sample for further investigation. A trait that NASA greatly values.
Looking forward
In summary, NASA said that from its results from the 8 months, the Bobcat air sampler was tested, "appears to be an effective way to collect biological samples from astromaterials curation cleanrooms without introducing unwanted organic contaminants associated with impactor style samplers".
Adding that dedicated biological air sampling is necessary because high particle counts do not always appear to correlate with large numbers of culturable organisms. This result implies that most of the particles in these labs are not viable cells.
Looking into what they need to do in the future, NASA said that further work is needed to optimise the sampling time for these cleanrooms.