[O-02] Why do organisms create biominerals? ~Advancement of science by blending of Art-thinking~

[O02-P03] "Biomineralization as Viewed from the Study of Water"

*Yuki Araki¹ (1.Kanazawa University)

Keywords:Interfacial water, Biomineralization, Frequency modulation atomic force microscopy

Water is an essential substance for sustaining the life activities of all organisms and has benefited our cultural life from food production to art. While water is necessary as a medium for various physical and chemical phenomena, its role as the protagonist in these phenomena is rarely discussed due to its familiarity. However, with the recent advancements in measurement techniques, research focusing on water as the observation target has been increasing, drawing attention to its importance. In this study, we have applied the frequency-modulation atomic force microscope (FM-AFM) to observe the structure of solid-liquid interfaces at the atomic and molecular scale and have investigated the interfacial water structure of calcium carbonate, which is also used in biomineralization. As a result, it was found that magnesium ions, a key substance in the phase transition phenomenon of crystal polymorphism during the biomineralization of calcium carbonate, significantly alter the structure of interfacial water. Additionally, observations of ion adsorption on clay mineral surfaces using FM-AFM suggest the potential of water to promote ordered ion adsorption. In everyday life, water plays a role in facilitating the adsorption and transport of substances, and based on our research results, it is believed that microscale interfacial water with a thickness of less than 1 nm also plays a crucial role in adsorption and transport. In the presentation, we focus on the role of interfacial water inmicroscopic phenomena and aim to deepen understanding of the importance of water in biomineralization through discussions with experts in the field of art.