Typologie d'actualités: Team Chemistry, Imaging and Exobiology

Multiplex imaging in the NIR-II window with lanthanide-based molecular agents: a dream or a reality?

In this work we have created a new family of lanthanide-based molecular imaging agents that can be used for multiplex imaging in the second near-infrared window (NIR-II, 1000-1700 nm). NIR-II light is particularly interesting for non-invasive, real-time imaging and diagnosis of living organisms, as it is unaffected by the native fluorescence of biological tissues and fluids, and can penetrate through them. In addition, multiplex imaging enables the simultaneous, real-time visualization of several biological markers for even more precise diagnosis of diseases and a deeper understanding of biological processes. This new family of molecular imaging agents is based on an innovative design and combines the exceptional advantages of “metallacrowns” to emit NIR-II light with those of ruthenium complexes, which exhibit strong absorption in the visible range and effectively sensitize lanthanides. Using NIR-II imaging experiments, we have been able to demonstrate that four bands from three different lanthanides can be distinguished unambiguously due to their minimal overlap, while exhibiting sufficient intensity to be detected through a tissue-mimicking phantom.

Enabling Visible Light Sensitization of YbIII, NdIII and ErIII in Dimeric LnIII/GaIII Metallacrowns through Functionalization with RuII Complexes for NIR-II Multiplex Imaging
Codruţa C. Bădescu-Singureanu, Dr. Anton S. Nizovtsev, Prof. Dr. Vincent L. Pecoraro, Prof. Dr. Stéphane Petoud, Dr. Svetlana V. Eliseeva
Angewandte Chemie International Edition 2024
https://doi-org.inc.bib.cnrs.fr/10.1002/anie.202416101

This article was reported by CNRS Chimie on its website.

Welcome to Nikola Baslerova !

Doctoral student Nikola Baslerova is joining the “Molecular Assemblies and Complex Systems” team for a 3-month Erasmus stay, as part of a collaboration with the University of Pardubice in the Czech Republic.

Currently in her third year of doctoral studies, she carries out her research in the field of microbiology, but collaborates with chemists. The title of her thesis is “Determination of the biological activity of boranes and heteroboranes”.

At CBM, she studies the cytotoxicity of certain synthetic molecules, in particular complex, polyhedral boranes and heteroboranes. These compounds are of potential interest for certain biomedical applications, which are currently being explored.

Contrast agents to combine 1H and 19F MRI

Today, magnetic resonance imaging (MRI) is based on the detection of water protons (1H) in tissues. MRI of 19F fluorine offers complementary advantages, but its use is hampered by a lack of suitable imaging agents, soluble in water and easily detectable. In order to improve the sensitivity of detecting 19F MRI signals, a CBM team used Mn2+ ions to form complexes with small fluorinated molecules. Unlike currently used nanoparticles, these small molecular probes have well-defined chemical structures and better biocompatibility and water solubility. Finally, thanks to the paramagnetism of manganese(II), they generate a strong signal in MRI. In addition, these fluorinated contrast agents are also active in proton MRI, allowing proton and fluorine MRI images to be superimposed for precise anatomical mapping.

This advance, published in Angewandte Chemie International Edition, opens new horizons in fluorine MRI. It was reported by CNRS Chimie on its website.

Reference :
Small, Fluorinated Mn2+ Chelate as an Efficient 1H and 19F MRI Probe
Éva Tóth, Zoltán Garda, Frédéric Szeremeta, Océane Quin, Enikő Molnár, Balázs Váradi, Rudy Clémençon, Sandra Même, Chantal Pichon and Gyula Tircsó
Angewandte Chemie International Edition, 2024
DOI: 10.1002/anie.202410998