Article Hinokitiol-fueled disks form exclusionary zones in the presence of iron

Lara Rae Holstein SAMURAI ORCID (Research Center for Macromolecules and Biomaterials/Macromolecules Field/Molecular Design and Function Group, National Institute for Materials Science) ; Megan S. Santamore (Research Center for Macromolecules and Biomaterials/Macromolecules Field/Molecular Design and Function Group, National Institute for Materials Science) ; Asahi Tsukamoto (Research Center for Macromolecules and Biomaterials/Macromolecules Field/Molecular Design and Function Group, National Institute for Materials Science) ; Masayuki Takeuchi SAMURAI ORCID (Research Center for Macromolecules and Biomaterials/Macromolecules Field/Molecular Design and Function Group, National Institute for Materials Science) ; Nobuhiko J. Suematsu (Meiji University) ; Atsuro Takai SAMURAI ORCID (Research Center for Macromolecules and Biomaterials/Macromolecules Field/Molecular Design and Function Group, National Institute for Materials Science)

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Lara Rae Holstein, Megan S. Santamore, Asahi Tsukamoto, Masayuki Takeuchi, Nobuhiko J. Suematsu, Atsuro Takai. Hinokitiol-fueled disks form exclusionary zones in the presence of iron. RSC Advances. 2026, 16 (14), 12725-12729. https://doi.org/10.1039/D6RA01403H

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(abstract)

Stimuli-responsive, directional motions, such as chemotaxis, are vital for the development of sophisticated synthetic systems with autonomous motility. Here, we demonstrate that disks containing hinokitiol exhibit directional self-propelled motion on water in response to metal ions, particularly Fe(III) ion. The self-propelled motion arises from surface tension gradients at the air–water interface, generated by the asymmetric release of hinokitiol, which induce Marangoni flows that propel the disks. Upon contact with Fe(III), hinokitiol forms a highly surface-active complex that locally lowers the surface tension and establishes a persistent interfacial gradient. This localized accumulation of the iron complex acts as a chemo-repulsive signal, directing the disks away from iron-rich regions and leading to the formation of exclusionary zones that influence the trajectories of subsequent disks. These findings demonstrate how self-secreted chemical signals can generate interfacial memory and communication in macroscopic active systems, providing a molecular design principle for life-like collective behavior.

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Keyword: Hinokitiol, Chemotaxis, Self-propelled motion

Date published: 2026-03-06

Publisher: Royal Society of Chemistry (RSC)

Journal:

  • RSC Advances (ISSN: 20462069) vol. 16 issue. 14 p. 12725-12729

Funding:

  • Ministry of Education, Culture, Sports, Science and Technology JPMXP0724020292
  • Ministry of Education, Culture, Sports, Science and Technology JPMXP1224NM5109
  • Ministry of Education, Culture, Sports, Science and Technology JPMXP1225NM5064
  • Japan Society for the Promotion of Science JP21H01004
  • Japan Society for the Promotion of Science JP23K03347
  • Japan Society for the Promotion of Science JP23K04725
  • Japan Society for the Promotion of Science JP24H01734
  • Japan Society for the Promotion of Science JP24K01475
  • Inamori Foundation

Manuscript type: Publisher's version (Version of record)

MDR DOI:

First published URL: https://doi.org/10.1039/D6RA01403H

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Updated at: 2026-03-10 12:30:04 +0900

Published on MDR: 2026-03-10 09:03:20 +0900

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Filename d6ra01403h1.pdf
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