Lanthanide‐Based Conjugates as Polyvalent Probes for Biological Labeling

Autor: Loïc J. Charbonnière, Raymond Ziessel, Éva Tóth, Isabelle Raynal, Marc Port, Thomas Chauvin, Nicolas Weibel, Jérôme Steibel, Stéphanie Claudel-Gillet
Přispěvatelé: Laboratoire de chimie moléculaire (LCM), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Imagerie et de Neurosciences Cognitives, Centre de biophysique moléculaire (CBM), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Guerbet Research, Guerbet
Rok vydání: 2008
Předmět:
Zdroj: European Journal of Inorganic Chemistry
European Journal of Inorganic Chemistry, Wiley-VCH Verlag, 2008, pp.2856-2862. ⟨10.1002/ejic.200800269⟩
ISSN: 1099-0682
1434-1948
Popis: International audience; A series of lanthanide complexes of [LnL(H2O)] composition, suitable for biological labeling has been studied, in which L is a strongly chelating ligand containing chromophoric bipyridylcarboxylate units and Ln = Sm, Eu, Gd, Tb, and Dy. For the Gd complex, a combined 17O NMR and 1H NMRD study has been performed. The water exchange rate obtained, kex298 = (5.2 ± 0.6) × 106 s-1, is slightly higher than those for [Gd(dota)(H2O)]- or [Gd(dtpa)(H2O)]2-. Transformation of the uncoordinated carboxylate function of the ligand into an activated ester ensures covalent linking of the complex to bovine serum albumine (BSA). The relaxivity properties of the Gd complex labeled on BSA revealed a limited increase of both longitudinal and transversal relaxivities. This can be related to the partial replacement of the inner-sphere water molecules by coordinating functions of the protein. Additionally, the Sm and Dy complexes are described and chemically characterized. Their photophysical properties were investigated by means of absorption, steady-state and time-resolved spectroscopy, evidencing efficient photosensitization of the lanthanide emission by ligand excitation (antenna effect). Luminescence lifetime measurements confirmed the presence of a water molecule in the first coordination sphere that partly explained the relatively poor luminescence properties of the Dy and Sm complexes in aqueous solutions. The spectroscopic properties of the series of complexes are questioned in terms of time-resolved acquisition techniques. Finally, their availability for use in time-resolved luminescence microscopy is demonstrated by staining experiments of rat brain slices, where the complex showed enhanced localization in some hydrophilic regions of the blood-brain barrier (BBB).
Databáze: OpenAIRE
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