Gas-sensing studies of microbial contaminated surfaces

Microbial contaminations in space stations present a major risk for the crew and the construction materials. In order to set guidelines for using gas-sensing to verify these microbial contaminations, spaceship components were contaminated with micro-organisms and investigated using the Electronic nose ENO-1. Under laboratory conditions the gas sensing experiment to identify the species, the kind of substrate or material, and the composition of a mixed population as influencing factors for variance in the microbial emissions was successful. The emissions are composed of the outgassing from substrate or material and the gaseous products of the microbial metabolism. Microbial emissions are further affected by the age or physiological state of a culture and interactions in mixed populations. The many influencing factors lead to high variability of the emissions from a microbial contamination and hinder the correct classification. Additionally, changing background conditions and low concentrations of microbial emissions complicate gas-sensing monitoring for microbial contamination in space stations