(562i) Micro-Scale Chaotic Advection Enables Targeted and Accelerated Surface Chemistry in Prebiotic Hydrothermal Environments

Ugaz, V. M., Texas A&M University
Priye, A., Sandia National Laboratory

Porous mineral formations near subsea hydrothermal vents embed richly complex microenvironments likely to have fostered emergence of complex macromolecules from dilute organic precursors in the prebiotic ocean. But a unified framework explaining how surface-mediated synthesis can be orchestrated by the interplay among physical, chemical, and thermal processes within these catalytically active networks remains elusive. Here we show how microscale thermally actuated chaotic flows, naturally established over a broad range of hydrothermally relevant pore sizes, function as highly efficient conveyors to continually shuttle molecular precursors (e.g., DNA oligonucleotides) from the bulk fluid to targeted locations on the solid boundaries. We quantitatively map enrichment of biomolecular species achievable via this process, and introduce an in situ approach to directly probe its influence on surface reaction kinetics. Our results demonstrate that chaotic thermal convection is capable of enabling greatly accelerated chemical synthesis at bulk species concentrations several orders of magnitude lower than previously thought possible, contradicting established thinking regarding the impact of chaos on interfacial transfer processes.