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Updated: Jul 1, 2026
Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
Metallo supramolecular assemblies of bis-squaraines by allosteric Ca2+ ion binding
Shigeyuki Yagi1, Yutaka Hyodo, Masahiko Hirose
1Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, Sakai, Osaka, Japan. yagi@chem.osakafu-u.ac.jp
Abstract:
Alkyl chain tethered bis-squaraines bind to Ca2+ ions through the participation of the negatively charged oxygen of the central cyclobutene moiety to form folded H-type aggregates. The initially formed Ca2+ complex is preorganized to facilitate cooperative allosteric binding of Ca2+, resulting in the formation of extended supramolecular arrays. The electronic absorption, IR, and ESI-MS studies support the formation of metallo supramolecular architectures of the folded H-type dimers of the bis-squaraines.
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