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Updated: May 11, 2026

Visualizing Intracellular Sialylation with Click Chemistry and Expansion Microscopy
Published on: February 7, 2025
New molecular motif for recognizing sialic acid using emissive lanthanide-macrocyclic polyazacarboxylate complexes:
Kazuki Ouchi1, Shingo Saito, Masami Shibukawa
1Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, Japan.
Abstract:
A new molecular motif--lanthanide-macrocyclic polyazacarboxylate hexadentate complexes, Ln(3+)-ABNOTA--was found to specifically bind to sialic acid with strong emission enhancement and high affinity. The selectivity toward sialic acid over other monosaccharides was one of the highest among artificial receptors. Also, the novel binding mechanism was investigated in detail; binding selectivity is controlled by interactions between sialic acid and both the central metal and a hydroxyl group produced by deprotonation of a coordinated water molecule in the Ln(3+) complex.
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