Institut de Chimie Moléculaire et des Matériaux d'Orsay

Magnetic nanosystems

Axis 1 - Coordination nanoparticles for biomedical applications

Coordination networks such as Prussian Blue Analogs and other related cyanide-bridged polymers are highly appealing materials for the design of new nano-objects for imaging (MRI, PET…) and theranostics. The high insolubility of such compounds is a strong advantage compared to most Metal-Organic-Frameworks, as well as their green synthesis and chemical versatility. The preparation of controlled sub-10 nm nanoparticles with a core-shell architecture in water has been successfully achieved. The localization of the active ions such as Mn^II and Gd^III at the periphery leads to exceptional longitudinal relaxivity  (up to 16 mM^-1s^-1/Mn^II to 40 mM^-1s^-1/Gd^III). A large T₁-weighted contrast enhancement is observed at high field (7 T) and low concentration, reducing the amount of injected metals and providing a much larger contrast than clinical agents. Post-coating by various biocompatible polymers helps assessing the role of the polymer nature and amount for optimizing the efficiency of the nanosized contrast agents. Theranostics including photothermal therapy, radio and hadrontherapy are pursued in strong collaboration with experts of the fields and are supported within the IRS Nanotherad of the Paris Saclay University.

(left) Confocal image showing cell internalization of MnInFe nanoparticles coated with dextran-TRITC

(right, top) Bright T₁ contrast enhancement obtained under 7T with MnInFe nanoparticles (NP, 0.2 mM in Mn^II) compared to a clinical agent (GdDTPA, 0.2 mM in Gd^III) and water

(right, bottom) TEM image of MnInFe nanoparticles coated with dextran

Last update on 06.21.2019