The adsorption of adenine and thymine in komatiite and tonalite simulating the complexity of the primordial terrestrial crust
Adsorción de adenina y timina en komatiita y tonalita simulando la complejidad de la corteza terrestre primordial
Abigail Elvira Cruz-Hernández1
, María Colín-García2, Eva Mateo-Martí3
1 Posgrado en Ciencias de la Tierra, Universidad Nacional Autónoma de México. Circuito de Posgrados s/n, Ciudad Universitaria, Coyoacán, 04510, Ciudad de México, México.
2 Instituto de Geología, Universidad Nacional Autónoma de México. Circuito de la Investigación Científica, Ciudad Universitaria, 04510, Ciudad de México, México.
3 Centro de Astrobiología (CAB), Instituto Nacional de Técnica Aeroespacial (INTA), Consejo Superior de Investigaciones Científicas (CSIC). Ctra. Ajalvir Km 4, Torrejón de Ardoz, 28850, Madrid, España.
Corresponding author: (A. E. Cruz-Hernández) This email address is being protected from spambots. You need JavaScript enabled to view it.
How to cite this article:
Cruz-Hernández, A. E., Colín-García, M., & Mateo-Martí, E. (2026). The adsorption of adenine and thymine in komatiite and tonalite simulating the complexity of the primordial terrestrial crust: Boletín de la Sociedad Geológica Mexicana, 78(2), A170226. https://doi.org/10.18268/BSGM2026v78n2A170226
Manuscript received: December 10, 2025. Corrected manuscript received: February 12, 2026. Manuscript accepted: February 14, 2026.
ABSTRACT
Mineral surfaces may have played a fundamental role in the chemical processes that led to the origin of life by concentrating and transforming organic molecules into primitive aqueous environments. Hence, the adsorption potential of rocks representative of the primordial oceanic (komatiite) and continental (tonalite) crusts, as well as their main constituent minerals (lizardite and plagioclase), towards the nucleobases adenine and thymine was evaluated in this study. Batch adsorption experiments were performed in aqueous suspension at different time intervals, and the surfaces were characterized to determine their mineral and elemental composition, as well as their pore structure. The results showed that all studied surfaces adsorbed both molecules, with a higher affinity toward adenine. Thymine exhibited a bell-shaped kinetic trend for almost all surfaces (except komatiite and lizardite), possibly associated with conformational changes induced by silicate minerals. The differences observed between rocks and their constituent minerals are attributed to the heterogeneity of adsorption sites. These findings suggest that surface–molecule interactions involve different mechanisms and even catalytic sites that are dependent on surface composition. This work highlights the relevance of rock surfaces as potential concentrators of organic molecules in prebiotic scenarios.
Keywords: komatiite, tonalite, lizardite, plagioclase, adsorption, nucleobases.