A Supercritical Pathway for Biomimetic Membrane Formation in Extra-Terrestrial Environments

Cell membranes are complex structures that are robust enough to withstand changes in temperature and pressure, yet are stable and flexible enough to cope with a vast library of cellular processes. However, the mild conditions on Earth - conditions where water is liquid and membranes can be thermally stable - are famously scarce in the vastness of space. Recent data collected by the Cassini-Huygens probe, and subsequently studied by computer modelling has shown that some nitrogen-containing “tholin” molecules may be able to spontaneously form membrane-like structures in the cold liquid methane lakes on Titan, one of the moons of Saturn. In this experiment we will recreate this atmosphere at ISIS by cooling a tholin solution in supercritical methane to cryogenic temperatures, and probing the behaviour of these systems using neutron scattering.