Skip to Main content Skip to Navigation
Journal articles

A bioinspired luminescent europium-based probe capable of discrimination between Ag+ and Cu+

Manon Isaac 1 Sergey Denisov 2 Nathan D. Mcclenaghan 2, * Olivier Sénèque 1, *
* Corresponding author
1 PMB - Physiochimie des Métaux
LCBM - UMR 5249 - Laboratoire de Chimie et Biologie des Métaux
Abstract : Due to their similar coordination properties, discrimination of Cu + and Ag + by water-soluble luminescent probes is challenging. We have synthesized LCC4 Eu , an 18 amino acid cyclic peptide bearing a europium complex, that is able to bind one Cu + or Ag + ion by the side chains of two methionines, a histidine and a 3-(1-naphthyl)-Lalanine. In this system, the naphthyl moiety establishes a cation- interaction with these cations. It also acts as an antenna for the sensitization of Eu 3+ luminescence. Interestingly, when excited at 280 nm behaves as a turn-on probe for Ag + (+150 % Eu emission) and as a turn-off probe for Cu + (-50% Eu 3+ emission). Shifting the excitation wavelength to 305 nm makes the probe responsive to Ag + (+380% Eu 3+ emission) but not to Cu + or other physiological cations. Thus, LCC4 Eu is uniquely capable of discriminating Ag + from Cu +. A detailed spectroscopic characterization based on steady state and time-resolved measurements clearly demonstrates that Eu 3+ sensitization relies on electronic energy transfer from the naphthalene triplet state to the Eu 3+ excited states and that the cation- interaction lowers the energy of this triplet state by 700 cm-1 and 2400 cm-1 for Ag + and Cu + , respectively. Spectroscopic data point to a modulation of the efficiency of the electronic energy transfer caused by the differential red-shift of the naphthalene triplet, deciphering the differential luminescence response of LCC4 Eu toward Ag + and Cu + .
Complete list of metadata
Contributor : Olivier Sénèque <>
Submitted on : Wednesday, June 23, 2021 - 8:46:08 AM
Last modification on : Wednesday, August 4, 2021 - 3:03:08 AM


Files produced by the author(s)




Manon Isaac, Sergey Denisov, Nathan D. Mcclenaghan, Olivier Sénèque. A bioinspired luminescent europium-based probe capable of discrimination between Ag+ and Cu+. Inorganic Chemistry, American Chemical Society, 2021, 60 (14), pp.10791-10798. ⟨10.1021/acs.inorgchem.1c01486⟩. ⟨hal-03268264⟩



Record views


Files downloads