Luminescence Bioimaging with Lanthanide Complexes

Photophysical investigation of near infrared emitting lanthanoid complexes incorporating tris(2-naphthoyl)methane as a new antenna ligand

“…The unique photophysical properties of the lanthanoid ions, such as characteristic line-like emission spectra and long luminescence lifetimes, have made them key elements in a range of technological applications. [1][2][3][4] Particular interest has been paid to the lanthanoids, Nd 3+ , Er 3+ and Yb 3+ , exhibiting near infrared (NIR) emission because of their potential applications in biological imaging 4,5 and telecommunications. 6 To obtain highly efficient emissive lanthanoid complexes, their chemical nature must be carefully designed accounting for the nature of interconfigurational electronic f-f transitions.…”

Energy transfer between Eu3+ and Nd3+ in near-infrared emitting β-triketonate coordination polymers

“…20,39 Following a similar procedure to that previously reported for the preparation of {[Ln(Cs)(tbm) 4 ] 2 } (Ln 3+ = Eu, Er, Yb) and {[Ln(Cs) (mtbm) 4 ] 2 } n (Ln 3+ = Eu, Er), 20 one equivalent of hydrated LnCl 3 (Ln 3+ = Eu, Nd) was made to react with four equivalents of mtbmH and four equivalents of RbOH in ethanol. Slow evaporation of the solvent resulted in the formation of suitable crystals for X-ray diffraction, revealing the formation of coordination polymers with formula {[Ln(Rb)(mtbm) 4 ] 2 } n where Ln 3+ = Eu(1), Nd (2). The compositions of the isolated species were further confirmed by elemental analysis and IR spectroscopy.…”

“…The NIR region is of particular interest due to potential applications in a wide range of fields including night vision devices, telecommunication signalling and life science. [1][2][3][4][5][6] Despite the listed advantages, trivalent lanthanoid cations cannot be directly excited with high efficiency, as intraconfigurational f-f transitions are parity and often spin forbidden. Therefore, π-conjugated ligands are routinely used as sensitisers, because of their greater efficiency in absorbing incident light with con-sequent energy transfer to lanthanoid excited states.…”

Lanthanoid complexes supported by retro-Claisen condensation products of β-triketonates

“…A variety of strategies for the design of luminescence trivalent lanthanoid compounds have been developed in the last few decades, due to their potential use as materials for biological imaging, optical display applications, night vision devices or telecommunication. [1][2][3][4][5][6][7] β-Triketones are one of the most recent ligand systems found to effectively sensitise the lanthanoid cations, with remarkable photophysical properties for the near-infrared emitters, in particular. 8 Furthermore, lanthanoid β-triketonate-based complexes present characteristic structures where discrete tetranuclear assemblies Ae2Ln2 can be linked to form polymers {Ae2Ln2}n depending on the synthetic conditions.…”