Ionic Liquid Biospheres

Area of Science:

• Astrobiology and Planetary Science
• Chemistry
• Biochemistry

Background:

• Life as we know it requires liquid, but water may not be the only possibility.
• Ionic liquids (ILs) and deep eutectic solvents (DES) possess unique physical properties making them candidates for non-aqueous planetary liquids.
• These properties include extremely low vapor pressures and wide liquid temperature ranges, allowing persistence in environments hostile to water.

Purpose of the Study:

• To propose and explore the hypothesis that ILs and DES can serve as planetary solvents for non-Earth-like life.
• To investigate the potential of ILs and DES to facilitate prebiotic chemistry on celestial bodies lacking liquid water.
• To examine the possibility that life elsewhere might evolve to utilize ILs and DES as intracellular solvents.

Main Methods:

• Review of existing studies on protein and biomolecule stability and functionality in ILs and DES.
• Analysis of planetary environments where ILs and DES could plausibly occur, considering available ionic components.
• Outline of strategies for advancing the IL/DES solvent hypothesis, including laboratory experiments, computational chemistry, and planetary mission data.

Main Results:

• ILs and DES can exist as stable liquids in a wide range of planetary conditions where water cannot.
• Biomolecules show demonstrated stability and functionality in ILs, supporting their potential as solvents for alien life.
• ILs and DES could provide long-lived, protective environments for complex organic molecules, crucial for prebiotic chemistry.

Conclusions:

• ILs and DES represent a viable class of non-aqueous solvents with significant implications for astrobiology.
• Their unique properties suggest they could host or enable life on a broader range of celestial bodies than previously considered.
• Further research combining laboratory, computational, and observational approaches is needed to validate the IL/DES solvent hypothesis.