Formation of vesicular structures from fatty acids formed under simulated volcanic hydrothermal conditions

Abstract

Abstract Microscopic compartmentalization is beneficial in synthetic chemistry and indispensable for the evolution of life to separate a reactive “inside” from a hydrolyzing “outside”. Here, we show compartmentalization in aqueous solution containing mixtures of fatty acids up to 19 carbon atoms which were synthesized by one-pot reactions of acetylene and carbon monoxide in contact with nickel sulfide at 105 °C, reaction requirements which are compatible to Hadean Early Earth conditions. Based on confocal, dynamic light scattering (DLS) and transmission electron microscopy (TEM) measurements, vesicle-like structures with diameters of 10–150 nm are formed after solvent extraction and resolubilisation. Moreover fluorescent dye was encapsulated into the structures proving their vesicular properties. This self-assembly could also have occurred on Early Earth as a crucial step in establishing simple membranes of proto-cells as a prerequisite in the evolution of metabolism and life.