Publications associées à Carbazole as Linker for Dinuclear Gadolinium-Based MRI Contrast Agents

129Xe Dynamic Nuclear Polarization Demystified: The Influence of the Glassing Matrix on the Radical Properties

Rolf Gruetter, Jean-Noël Hyacinthe, Andrea Capozzi, Thanh Phong Kevin Lê, Emma Linnea Wiström

129Xe dissolution dynamic nuclear polarization (DNP) is a controversial topic. The gold standard technique for hyperpolarized xenon magnetic resonance imaging (MRI) is spin exchange optical pumping, which received FDA approval in 2022. Nevertheless, the ve ...

2024

Magnetism of Single Surface Adsorbed Atoms Studied with Radio-Frequency STM

Clément Marie Soulard

This thesis investigates the magnetic properties of single atoms and molecules adsorbed on thin magnesium oxide decoupling layers, grown on a silver single crystal. To address these systems experimentally, we use a low temperature scanning tunneling micros ...

EPFL2024

Pore size estimation in axon-mimicking microfibers with diffusion-relaxation MRI

Jean-Philippe Thiran, Muhamed Barakovic, Erick Jorge Canales Rodriguez, Marco Pizzolato, Tim Bjørn Dyrby

Purpose: This study aims to evaluate two distinct approaches for fiber radius estimation using diffusion-relaxation MRI data acquired in biomimetic microfiber phantoms that mimic hollow axons. The methods considered are the spherical mean power-law approac ...

Wiley2024

Fast, Broad-Band Magnetic Resonance Spectroscopy with Diamond Widefield Relaxometry

Hoda Shirzad, Mayeul Sylvain Chipaux

We present an alternative to conventional Electron the use of bulky magnets and magnetron equipment, we use the photoluminescence of an ensemble of Nitrogen-Vacancy centers at the surface of a diamond. Monitoring their relaxation time (or T1), we detected ...

AMER CHEMICAL SOC2023

Dynamic Nuclear Polarization of Inorganic Halide Perovskites

Dominik Józef Kubicki, David Lyndon Emsley, Gabriele Stevanato, Aditya Mishra, Michael Allan Hope

The intrinsic low sensitivity of nuclear magnetic resonance (NMR) experiments limits their utility for structure determination of materials. Dynamic nuclear polarization (DNP) under magic angle spinning (MAS) has shown tremendous potential to overcome this ...

2023

Robust gamma-aminobutyric acid and energy metabolism measurements by proton and phosphorus magnetic resonance spectroscopy and fingerprinting

Songi Lim

Magnetic resonance spectroscopy (MRS) is the only technique that can detect endogenous metabolites directly and non-invasively in vivo. It allows to identify different metabolites and analyze the dynamic neurochemical processes in the brain, skeletal muscl ...

EPFL2023

Magnetic Resonance and Hyperpolarization Methods for Perovskite Photovoltaics

Aditya Mishra

Solid-state NMR can provide information about the atomic-level microstructure and dynamics in materials as it directly probes the local nuclear environment. In the last decade, halide perovskites have drawn intense interest because of their intriguing opto ...

EPFL2022

Diffusion-relaxation scattered MR signal representation in a multi-parametric sequence

Marco Pizzolato

This work focuses on obtaining a magnetic resonance imaging (MRI) signal representation that accounts for a longitudinal T-1 and transverse T-2* relaxations while at the same time integrating directional diffusion in the context of scattered multi-parametr ...

ELSEVIER SCIENCE INC2022

Variability and reproducibility of multi-echo T2 relaxometry: Insights from multi-site, multi-session and multi-subject MRI acquisitions

Jean-Philippe Thiran, Tobias Kober, Elda Fischi Gomez, Alessandro Daducci, Tom Hilbert, Elena Beanato, Gabriel Girard, Julia Brügger, Gian Franco Piredda, Friedhelm Christoph Hummel, Takuya Morishita, Maximilian Jonas Wessel, Philipp Johannes Koch, Erick Jorge Canales Rodriguez, Marco Pizzolato, Andéol Geoffroy Cadic-Melchior, Thomas Yu, Chang-Hyun Park

Quantitative magnetic resonance imaging (qMRI) can increase the specificity and sensitivity of conventional weighted MRI to underlying pathology by comparing meaningful physical or chemical parameters, measured in physical units, with normative values acqu ...

2022

Hyperpolarization of inorganic solids

Snaedis Björgvinsdóttir

Solid-state NMR can provide information about the atomic level structure and dynamics of materials. It directly probes symmetry and structure at nuclear sites, and is especially useful for investigation of disordered or amorphous solids that lack long rang ...

EPFL2020

Mechanistic studies of DNP and applications of hyperpolarized probes to study renal physiology and metabolism

Alice Radaelli

Dissolution dynamic nuclear polarization (dDNP) is a powerful technique that enhances the magnetic resonance signal of nuclear spins by several orders of magnitude. DNP relies on the principle of cross-relaxation by electron spins driven out of equilibrium ...

EPFL2021

Method for the preparation of a sample comprising highly polarized nuclear spins and uses and devices for such a method

Jean-Philippe Ansermet, Christophe Roussel, Jonas Milani, Mika Antero Tamski

Method for the preparation of a sample comprising highly polarized nuclear spins, comprising at least the following steps: a) bringing a polarization system, which using an electrochemical reaction can be converted into an EPR-active radical form thereof, ...

2021

Solid-state NMR spectroscopy

David Lyndon Emsley

Solid-state nuclear magnetic resonance (NMR) spectroscopy is an atomic-level method to determine the chemical structure, 3D structure and dynamics of solids and semi-solids. This Primer summarizes the basic principles of NMR spectroscopy as applied to the ...

SPRINGERNATURE2021

Endogenous O-17 Dynamic Nuclear Polarization of Gd-Doped CeO2 from 100 to 370 K

David Lyndon Emsley, Snaedis Björgvinsdóttir, Georges Guévork Jean-Jacques Menzildjian, Michael Allan Hope, Bowen Zhang, Moreno Lelli, Zhuoran Wang

O-17 NMR is an invaluable tool to study the structure and dynamics of oxide materials but remains challenging to apply in many systems. Even with isotopic enrichment, studies of samples with low masses and/or concentrations of the active species, such as t ...

2021

Methods to Enhance Nuclear Magnetic Resonance Sensitivity at High Magnetic Field

Claudia Christina Zanella

MR is a well-established technique routinely used in preclinical and clinical studies. This thesis focussed on the improvement of sensitivity of different methods in MR. Hyperpolarized 129Xe gas is used for studying pulmonary disease or cerebral perfusion ...

EPFL2021

Nanodiamond Relaxometry-Based Detection of Free-Radical Species When Produced in Chemical Reactions in Biologically Relevant Conditions

Mayeul Sylvain Chipaux

Diamond magnetometry is a quantum sensing method involving detection of magnetic resonances with nanoscale resolution. For instance, T1 relaxation measurements, inspired by equivalent concepts in magnetic resonance imaging (MRI), provide a signal that is e ...

AMER CHEMICAL SOC2020

Detection of myocardial medium‐chain fatty acid oxidation and tricarboxylic acid cycle activity with hyperpolarized [1– 13 C]octanoate

Arnaud Comment, Josefina Adriana Maria Bastiaansen, Hikari Ananda Infinity Yoshihara

Under normal conditions, the heart mainly relies on fatty acid oxidation to meet its energy needs. Changes in myocardial fuel preference are noted in the diseased and failing heart. The magnetic resonance signal enhancement provided by spin hyperpolarizati ...

2020

Normal volumetric and T1 relaxation time values at 1.5 T in segmented pediatric brain MRI using a MP2RAGE acquisition

Jean-Philippe Thiran, Bénédicte Marie Maréchal, Tobias Kober, Tom Hilbert, Gian Franco Piredda

Objectives This study introduced a tailored MP2RAGE-based brain acquisition for a comprehensive assessment of the normal maturing brain. Methods Seventy normal patients (35 girls and 35 boys) from 1 to 16 years of age were recruited within a prospective mo ...

SPRINGER2021

High-Field C-13 Dynamic Nuclear Polarization in Nanodiamond

Stefano Alberti, Jean-Philippe Ansermet, Serguei Sekatski, Jérémy Genoud, Murari Soundararajan, Dongyoung Yoon

Hyperpolarization in diamond via dynamic nuclear polarization (DNP) has attracted a lot of interest for various applications as diamond exhibits extremely long C-13 spin relaxation times and has endogenous polarizing agents in the form of crystalline defec ...

2019

Maximizing nuclear hyperpolarization in pulse cooling under MAS

Nicolas Luc Matthey, David Lyndon Emsley, Brennan James Walder

It has recently been shown how dynamic nuclear polarization can be used to hyperpolarize the bulk of proton-free solids. This is achieved by generating the polarization in a wetting phase, transferring it to nuclei near the surface and relaying it towards ...

Academic Press Inc - Elsevier Science2019