Lanthanide-based luminescence biolabelling

Abstract

Luminescent lanthanide complexes display unrivalled spectroscopic properties, which place them in a special category in the luminescent toolbox. Their long-lived line-like emission spectra are the cornerstones of numerous analytical applications ranging from ultrasensitive homogeneous fluoroimmunoassays to the study of molecular interactions in living cells with multiplexed microscopy. However, achieving such minor miracles is a result of years of synthetic efforts and spectroscopic studies to understand and gather all the necessary requirements for the labels to be efficient. This feature article intends to survey these criteria and to discuss some of the most important examples reported in the literature, before explaining in detail some of the applications of luminescent lanthanide labels to bioanalysis and luminescence microscopy. Finally, the emphasis will be put on some recent applications that hold great potential for future biosensing.

Highly luminescent lanthanide complexes sensitised by tertiary amide-linked carbostyril antennae

“…They have long emission lifetimes, narrow emission bands, are often highly photostable, and have negligible phototoxicities. [1][2][3][4][5][6] These properties are in sharp contrast to the rapid degradation, broad emission profiles and short lifetimes of organic emitters, or the toxicity of transition metal-based phosphorescent dyes or quantum dots. Ln(III) emission results from Laporte-forbidden f-f-transitions, and direct Ln(III) excitation is inefficient.…”

Luminescent Zinc Fingers: Zn‐Responsive Neodymium Near‐Infrared Emission in Water

“…[3] Fluorescence detection in biological samples is generally impaired by the scattering of light,b yt he strong absorption of biomolecules( at wavelengths lower than 600 nm) or water (in the near-infrared (NIR)), and by the intense intrinsic fluorescenceo fb iomolecules that are excitedi nt he ultraviolet-visible (UV/Vis) range. [8][9][10][11] Since most 4f-4ftransitions are forbidden by Laporte rules, the directe xcitation of Ln 3 + ions is inefficient due to extremely low extinction coefficients. [4][5][6] During the last decade, ac onsiderable effort has been devoted to the elaboration of NIR fluorescent probes based on organic dyes.…”

Design of a synthetic luminescent probe from a biomolecule binding domain: selective detection of AU-rich mRNA sequences

“…Trivalent lanthanide ions (Ln 3+ ) are appealing emitting moieties for biological sensing applications because of their desirable luminescence properties. 34–37 These properties include narrow emission bands that are not influenced by the environment, emission spectra covering the visible to NIR domain depending on Ln 3+ and long luminescence lifetimes that allow for time-resolved detection to suppress background fluorescence contributions. Additionally, sensitization of Ln 3+ luminescence requires the presence of a proximal chromophore, called an antenna.…”