Life Detection on Icy Moons Using Flow Cytometry and Exogenous Fluorescent Stains

Area of Science:

• Astrobiology
• Planetary Science
• Analytical Chemistry

Background:

• Flow cytometry is a promising technology for *in situ* life detection on extraterrestrial bodies like icy moons and Mars.
• Identifying key biomarkers is crucial for distinguishing life from abiotic materials in extreme environments.

Purpose of the Study:

• To develop and validate a flow cytometry method for identifying four classes of biomarkers (nucleic acids, proteins, carbohydrates, lipids) using exogenous fluorescent stains.
• To assess the effectiveness of this method in distinguishing between biotic and abiotic materials in simulated extraterrestrial samples.

Main Methods:

• Utilized flow cytometry with exogenous fluorescent stains targeting nucleic acids, proteins, carbohydrates, and lipids.
• Tested the method with six known organisms and abiotic materials.
• Analyzed six natural samples with unknown biotic/abiotic content to simulate a lander experiment.

Main Results:

• Successfully identified the four target biomarker classes using exogenous stains.
• Demonstrated the ability to clearly distinguish between known organisms and abiotic materials.
• Showcased the separation of biotic from abiotic material in natural samples using scatter plots.

Conclusions:

• Exogenous staining with flow cytometry is effective for *in situ* biomarker detection and life identification on icy moons and Mars.
• This technique, combined with intrinsic fluorescence and data analysis, enhances life detection capabilities for space missions.