Supramolecular Packing and Macroscopic Alignment Controls Actuation Speed in Macroscopic Strings of Molecular Motor Amphiphiles

Franco King Chi Leung, Tobias Van Den Enk, Takashi Kajitani, Jiawen Chen, Marc C.A. Stuart, Jeroen Kuipers, Takanori Fukushima, Ben L. Feringa

Research output: Journal article publicationJournal articleAcademic researchpeer-review

21 Citations (Scopus)


Three-dimensional organized unidirectionally aligned and responsive supramolecular structures have much potential in adaptive materials ranging from biomedical components to soft actuator systems. However, to control the supramolecular structure of these stimuli responsive, for example photoactive, materials and control their actuation remains a major challenge. Toward the design of "artificial muscles", herein, we demonstrate an approach that allows hierarchical control of the supramolecular structure, and as a consequence its photoactuation function, by electrostatic interaction between motor amphiphiles (MA) and counterions. Detailed insight into the effect of various ions on structural parameters for self-assembly from nano- to micrometer scale in water including nanofiber formation and nanofiber aggregation as well as the packing structure, degree of alignment, and actuation speed of the macroscopic MA strings prepared from various metal chlorides solution, as determined by electronic microscopy, X-ray diffraction, and actuation speed measurements, is presented. Macroscopic MA strings prepared from calcium and magnesium ions provide a high degree of alignment and fast response photoactuation. By the selection of metal ions and chain length of MAs, the macroscopic MA string structure and function can be controlled, demonstrating the potential of generating multiple photoresponsive supramolecular systems from an identical molecular structure.

Original languageEnglish
Pages (from-to)17724-17733
Number of pages10
JournalJournal of the American Chemical Society
Issue number50
Publication statusPublished - 19 Dec 2018
Externally publishedYes

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

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