Published October 2025 | Version v5
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Clay-Catalyzed Wet–Dry Cycling as a Systems-Chemistry Route to Proto-Life

Authors/Creators

  • 1. Professor of Physical chemistry, Faculty of Chemistry and Petroleum, Bu-Ali Sina University, Hamadan, Iran

Description

We propose a unified model in which fluctuating in which fluctuating wet-dry cycles on clay-rich mineral surfaces concentrate monomers, catalyse condensation into peptides and nucleic acids, and package reaction products into lipid-vesicle systems, thus generating protocells subject to primitive selection. Specifically, clay minerals act as adsorbers, concentrators and catalysts of polymerization, while recurrent dehydration/hydration cycles supply far-from-equilibrium driving force and reduce water-activity to favour condensation over hydrolysis. The scenario integrates elements of the “RNA world”, “lipid world” and “metabolism-first” models within a systems-chemistry framework, and leads to five experimentally accessible predictions: (1) polymer length and yield enhancements in clay + wet-dry systems, (2) autocatalytic cycles emerging from enriched oligomer populations, (3) amplification of enantiomeric excess (homochirality) with clay surfaces, (4) mineralogical/geochemical signatures in ancient sediments consistent with cycling, and (5) astrobiological implications for Mars and icy moons. We outline how this model can be quantitatively tested using montmorillonite (or smectite) clays, amino-/hydroxy-acids, nucleotides, and fatty-acid vesicles under defined cycling protocols.

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Additional details

Dates

Issued
2025-11-10

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