2025/10/29 by Timothée Lathion, Svetlana V. Eliseeva, Stéphane Pètoud +1 · 1 voice · 6 citations
Engineering · Materials Science · #Coumarin #Excitation #Fluorescence #Lanthanide #Lanthanide and Transition Metal Complexes #Ligand (biochemistry) #Linker #Luminescence and Fluorescent Materials #Organic Light-Emitting Diodes Research #Sensitization #Wavelength
paper · open access · doi:10.1021/acs.inorgchem.5c03669
published in Inorganic Chemistry 64(44), 22011-22020 (American Chemical Society)
openalex created_date 2025/10/29 · openalex publication_date 2025/10/29 · openalex updated_date 2026/07/30
High Resolution Image Download MS PowerPoint Slide Near-infrared (NIR)-emitting trivalent lanthanides (Ln III ) are attractive for applications such as biological imaging and telecommunications. However, their sensitization remains challenging, particularly at excitation wavelengths corresponding to low energies. To address this challenge, a new coumarin-bearing isophthalate-based bridging ligand ( C-ip 2– ), in which the coumarin sensitizer is directly attached to the bridge, was synthesized. In the corresponding [Ln 2 Ga 8 (shi) 8 (C-ip) 4 ] 2– metallacrowns (MCs), the sensitization of the NIR-emitting Nd III, Er III, and Yb III cations was achieved upon excitation of appended coumarins in the visible range (λ exc = 435 nm). Compared to the previous generation of [Ln 2 Ga 8 (shi) 8 (C-mip) 4 ] 2– MCs, the coumarin antennas are about 5 Å closer to the Ln III emissive centers in this new series of [Ln 2 Ga 8 (shi) 8 (C-ip) 4 ] 2– MCs, resulting in an increase in the Q Ln L values by factors of 6.2, 9.4, and 2.7 for Nd III, Er III, and Yb III analogues, respectively. This allows the detection of their NIR emissions through tissue-mimicking phantoms of 1 mm thickness, validating the potential of this design for NIR imaging applications.