Multifunctional Rare-Earth Vanadate Nanoparticles: Luminescent Labels, Oxidant Sensors, and MRI Contrast Agents

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• 作者：Mouna Abdesselem ; Markus Schoeffel ; Isabelle Maurin ; Rivo Ramodiharilafy ; Gwennhael Autret ; Olivier Cl茅ment ; Pierre-Louis Tharaux ; Jean-Pierre Boilot ; Thierry Gacoin ; Cedric Bouzigues ; Antigoni Alexandrou
• 刊名：ACS Nano
• 出版年：2014
• 出版时间：November 25, 2014
• 年：2014
• 卷：8
• 期：11
• 页码：11126-11137
• 全文大小：660K
• ISSN：1936-086X

文摘

Collecting information on multiple pathophysiological parameters is essential for understanding complex pathologies, especially given the large interindividual variability. We report here multifunctional nanoparticles which are luminescent probes, oxidant sensors, and contrast agents in magnetic resonance imaging (MRI). Eu³⁺ ions in an yttrium vanadate matrix have been demonstrated to emit strong, nonblinking, and stable luminescence. Time- and space-resolved optical oxidant detection is feasible after reversible photoreduction of Eu³⁺ to Eu²⁺ and reoxidation by oxidants, such as H₂O₂, leading to a modulation of the luminescence emission. The incorporation of paramagnetic Gd³⁺ confers in addition proton relaxation enhancing properties to the system. We synthesized and characterized nanoparticles of either 5 or 30 nm diameter with compositions of GdVO₄ and Gd_0.6Eu_0.4VO₄. These particles retain the luminescence and oxidant detection properties of YVO₄:Eu. Moreover, the proton relaxivity of GdVO₄ and Gd_0.6Eu_0.4VO₄ nanoparticles of 5 nm diameter is higher than that of the commercial Gd³⁺ chelate compound Dotarem at 20 MHz. Nuclear magnetic resonance dispersion spectroscopy showed a relaxivity increase above 10 MHz. Complexometric titration indicated that rare-earth leaching is negligible. The 5 nm nanoparticles injected in mice were observed with MRI to concentrate in the liver and the bladder after 30 min. Thus, these multifunctional rare-earth vanadate nanoparticles pave the way for simultaneous optical and magnetic resonance detection, in particular, for in vivo localization evolution and reactive oxygen species detection in a broad range of physiological and pathophysiological conditions.

Keywords:

lanthanide nanoparticles; multifunctional probe; oxidant sensor; contrast agent; MRI