2026-10-13T09:34:41Z https://www.scidb.cn/oai

10.57760/sciencedb.38813 2026-06-04T11:06:48Z

2026-06-04 Radiation effects on amino acids and implications for life detection on Mars doi:10.57760/sciencedb.38813 en Searching for signs of life is a central objective of current and future Mars exploration. Organic biomolecules, particularly amino acids, are considered key targets in life-detection efforts due to their well-established biological relevance. However, the thin Martian atmosphere and the absence of a global magnetic field expose the surface to intense ionizing radiation, rendering organic molecules highly susceptible to radiolytic degradation and potential destruction. To evaluate the stability of such biomolecules, numerous irradiation simulation experiments have been conducted. However, the survivability and chemical reactivity of amino acids under Martian-like conditions remain controversial. One possible reason is the inconsistent physical states of amino acids used in these studies, such as solution, solid powders, and single crystals. In this work, we systematically investigate the radiation stability of amino acids in different physical states under 60Co γ-rays irradiation. The results demonstrate that the radiation stability of amino acids is strongly dependent on their physical state. After exposure equivalent to ~31.2 Ma of Martian surface irradiation, the single crystal glycine remains largely intact, whereas solid powder glycine transforms from the monoclinic α-phase to the hexagonal γ-phase. In contrast, glycine in aqueous solution shows significant modification, involving both decomposition and complex recombination or polymerization. These findings provide new insights into the radiation-driven evolution of organic molecules on Mars and offer critical constraints for interpreting ambiguous spectroscopic signatures obtained from Martian surface analyses. 60Co γ-rays irradiation; amino acids; radiolysis; extraterrestrial life; Mars li xin L i X i n Liu Wenping Hu Qitao Zhou Zimeng Yin Wei Yao Qizhi Wang Mozhen Gao Xiaoying Qu Linfeng Su Jinyue Qu Xianchao Zhou Gentao EMBARGO https://creativecommons.org/licenses/by-nc-nd/4.0/ dataset Science Data Bank