Lothar Helm

lothar.helm@epfl.ch +41 21 693 98 76 http://gcib.epfl.ch

EPFL SB-DO
CH H3 605 (Bâtiment CH)
Station 6
CH-1015 Lausanne

+41 21 693 98 76
Local: CH H3 605
EPFL > SB > SB-DEC > PH-SB

Biographie

Lothar Helm was born in Gernsbach (Germany) in 1952. He studied physics at the University of Karlsruhe (Germany) and obtained his diploma degree in 1977. He remained in Karlsruhe for his Ph.D. research with Prof. H. G. Hertz and received his degree in physical chemistry in 1980. In 1980 he joined the laboratories of Prof. André Merbach at the University of Lausanne, Switzerland. From 1983 to 2001 he was maître denseignement et de recherche at the Faculty of Science of the University of Lausanne. In 2001 he moved, together with the whole chemistry department, from the University of Lausanne to the Ecole Polytechnique Fédérale de Lausanne (EPFL). Since 2006 he is adjunct professor at the Institute of Chemical Sciences and Engineering at EPFL and director of the NMR services of the institute.

From 2007 to 2011 he was director of the "Conférence du corps Enseignant" at EPFL. Since 2011 he is member of the School Assembly of EPFL (AE).

MAIN RESEARCH INTERESTS:
Physico-chemical studies of contrast agents for medical magnetic resonance imaging (MRI)
Study of reactivity and reaction mechanisms in coordination chemistry by variable temperature and pressure nuclear magnetic resonance
Computer simulation of solvent dynamics on cations and metal complexes in solution

Professional course

Publications

Publications Infoscience

Publications 2004 - 2014

Pharmacokinetics and biodistribution study of self-assembled Gd-micelles demonstrating blood-pool contrast enhancement for MRI

V. Vorobiev; A. Babic; L. A. Crowe; Y. Van de Looij; S. Lenglet et al.

International Journal of Pharmaceutics. 2019-09-10. DOI : 10.1016/j.ijpharm.2019.118496.

Lothar Helm

Biographie

Publications

Publications Infoscience

Publications 2004 - 2014

Pharmacokinetics and biodistribution study of self-assembled Gd-micelles demonstrating blood-pool contrast enhancement for MRI

The Periodic Table and Kinetics?

MRI micelles self-assembled from synthetic gadolinium-based nano building blocks

Self-Assembled Nanomicelles as MRI Blood-Pool Contrast Agent

Carbazole as Linker for Dinuclear Gadolinium-Based MRI Contrast Agents

In-Vivo Detection and Tracking of T Cells in Various Organs in a Melanoma Tumor Model by F-19-Fluorine MRS/MRI

Collisional cross-section of water molecules in vapour studied by means of H-1 relaxation in NMR

Transient versus Static Electron Spin Relaxation in Mn2 Complexes Relevant as MRI Contrast Agents

Evaluation of Water Exchange Kinetics on [Ln(AAZTAPh–NO2)(H2O)q]x Complexes Using Proton Nuclear Magnetic Resonance

Complexation of [Gd(DTTA–Me)(H2O)2]− by Fluoride and Its Consequences to Water Exchange

Water Exchange on [Ln(DO3A)(H2O)2] and [Ln(DTTA–Me)(H2O)2]− Studied by Variable Temperature, Pressure, and Magnetic Field NMR

PEGylated DOTA-AHA-Based Gd-III Chelates: A Relaxometric Study

A Pyridine-Based Ligand with Two Hydrazine Functions for Lanthanide Chelation: Remarkable Kinetic Inertness for a Linear, Bishydrated Complex

Metal Complexes as MRI Contrast Enhancement Agents

Dinuclear DOTA-Based Gd-III Chelates - Revisiting a Straightforward Strategy for Relaxivity Improvement

Prototropic Exchange Governs T-1 and T-2 Relaxivities of a Potential MRI Contrast Agent Nanozeolite Gd-LTL with a High pH Responsiveness

Gold nanoparticles functionalised with fast water exchanging Gd3 chelates: linker effects on the relaxivity

Solvent Exchange and Electron-Spin Relaxation on Homoleptic Acetonitrile Complexes of Trivalent Lanthanides

Gd(DOTAlaP): Exploring the Boundaries of Fast Water Exchange in Gadolinium-Based Magnetic Resonance Imaging Contrast Agents

Dynamic aggregation of the mid-sized gadolinium complex {Ph-4[Gd(DTTA)(H2O)(2)](-)(3)}

Relaxivity of gadolinium(III) complexes: theory and mechanism

The Chemistry of Contrast Agents in Medical Magnetic Resonance Imaging

Speciation of aqueous tellurium(IV) in hydrothermal solutions and vapors, and the role of oxidized tellurium species in Te transport and gold deposition

H-1 and O-17 NMR Relaxometric and Computational Study on Macrocyclic Mn(II) Complexes

Gadolinium complexes of monophosphinic acid DOTA derivatives conjugated to cyclodextrin scaffolds: efficient MRI contrast agents for higher magnetic fields

Hyperfine Coupling Constants on Inner-Sphere Water Molecules of Gd-III-Based MRI Contrast Agents

NMR and Electron Paramagnetic Resonance Studies of [Gd(CH3CN)(9)](3 ) and [Eu(CH3CN)(9)](2 ): Solvation and Solvent Exchange Dynamics in Anhydrous Acetonitrile

New Bisaqua Picolinate-Based Gadolinium Complexes as MRI Contrast Agents with Substantial High-Field Relaxivities

Serum Albumin Targeted, pH-Dependent Magnetic Resonance Relaxation Agents

Isoquinoline-Based Lanthanide Complexes: Bright NIR Optical Probes and Efficient MRI Agents

Pyridine-Based Lanthanide Complexes Combining MRI and NIR Luminescence Activities

O-17 NMR and Density Functional Theory Study of the Dynamics of the Carboxylate Groups in DOTA Complexes of Lanthanides in Aqueous Solution

Electronic fine structure calculation of [Gd(DOTA)(H2O)]- using LF-DFT: The zero field splitting

Mn2 Complexes with 12-Membered Pyridine Based Macrocycles Bearing Carboxylate or Phosphonate Pendant Arm: Crystallographic, Thermodynamic, Kinetic, Redox, and 1H/17O Relaxation Studies

The challenge of T1 contrast agents for high-magnetic field MRI

Gadolinium-Based Bionanomaterials for Magnetic Resonance Imaging

NMR Study of Ligand Exchange and Electron Self-Exchange between Oxo-Centered Trinuclear Clusters [Fe3(μ3-O)(μ-O2CR)6(4-R´py)3] /0

Synthesis, complexation and NMR relaxation properties of Gd3 complexes of Mes(DO3A)3

NMR of Insensitive Nuclei Enhanced by Dynamic Nuclear Polarization

Isomerization Mechanisms of Stereolabile tris- and bis-Bidentate Octahedral Cobalt(II) Complexes: X-ray Structure and Variable Temperature and Pressure NMR Kinetic Investigation

Geometrical confinement of gadolinium-based contrast agents in nanoporous particles enhances T1 contrast

Kinetics of Yttrium-Ligand Complexation Monitored Using Hyperpolarized 89Y as a Model for Gadolinium in Contrast Agents

Optimization of gadolinium-based MRI contrast agents for high magnetic‑field applications

Gadolinium(III) complexes of 1,4,7-triazacyclononane based picolinate ligands: simultaneous optimization of water exchange kinetics and electronic relaxation

Multiple Frequency and Variable Temperature EPR study of Gd(III) polyaminocarboxylates: analysis and comparison of the magnetically dilute powder and the frozen solution spectra

Gold Nanoparticles Functionalized with Gadolinium Chelates as High-Relaxivity MRI Contrast Agents

Lanthanide chelates of (bis)-hydroxymethyl-substituted DTTA with potential application as contrast agents in magnetic resonance imaging

Synthesis, structures and characterisations of truly homoleptic acetonitrile Ln3 complexes in solid state and in solution

A ruthenium-based metallostar: synthesis, sensitized luminescence and 1H relaxivity

Mechanism of Pyridine-Ligand Exchanges at the Different Labile Sites of 3d Heterometallic and Mixed Valence μ3-oxo Trinuclear Clusters

Nuclear Spin Relaxation Parameters of MRI Contrast Agents – Insight from Quantum Mechanical Calculations

Ligand exchange and complex formation kinetics studied by NMR exemplified on fac-[(CO)3M(H2O)] (M = Mn, Tc, Re)

In vivo MRI assessment of a novel GdIII-based contrast agent designed for high magnetic field applications

Physicochemical Properties of the High-Field MRI-Relevant [Gd(DTTA-Me)(H2O)2]− Complex

Novel DOTA-based prochelator for divalent peptide vectorization: synthesis of dimeric bombesin analogues for multimodality tumor imaging and therapy

Comparison of different methods for calculating the paramagnetic relaxation enhancement of nuclear spins as a function of the magnetic field

Gd(III)-EPTPAC16, a new self-assembling potential liver MRI contrast agent: in vitro characterization and in vivo animal imaging studies

A benzene-core trinuclear GdIII complex: towards the optimization of relaxivity for MRI contrast agent applications at high magnetic field

Gadonanotubes as Ultrasensitive pH-Smart Probes for Magnetic Resonance Imaging

Towards the Rational Design of MRI Contrast Agents: Electron Spin Relaxation Is Largely Unaffected by the Coordination Geometry of Gadolinium(III)-DOTA-Type Complexes

Physicochemical and MRI characterization of Gd3 -loaded polyamidoamine and hyperbranched dendrimers

H5EPTPACH2OH: Synthesis, Relaxometric Characterization and 1H NMR Spectroscopic Studies on the Solution Dynamics of Its LnIII Complexes

Magnetism induced by single-atom defects in nanographites

Gadolinium(III) ion in liquid water: structure, dynamics and magnetic interactions from first principles

Multiple-frequency EPR spectra of two aqueous Gd3 polyaminopolypyridinecarboxylate complexes: a study of high field effects

Understanding Paramagnetic Relaxation Phenomena for Water-Soluble Gadofullerenes

Early stages of radiation damage in graphite and carbon nanostructures: A first-principles molecular dynamics study

Defect-induced magnetism in graphene

Gadolinium(III) complexes of mono-and diethyl esters of monophosphinic acid analogue of DOTA as potential MRI contrast agents: solution structures and relaxometric studies

Design of Gd(III)-Based Magnetic Resonance Imaging Contrast Agents: Static and Transient Zero-Field Splitting Contributions to the Electronic Relaxation and Their Impact on Relaxivity

Kinetic studies on the first dihydrogen aquacomplex, [Ru(H2)(H2O)5]2 : Formation under H2 pressure and catalytic H/D isotope exchange in water

Relevance of the Ligand Exchange Rate and Mechanism of fac-[(CO)3M(H2O)3] (M = Mn, Tc, Re) Complexes for New Radiopharmaceuticals

Unexpected Aggregation of Neutral, Xylene-Cored Dinuclear GdIII Chelates in Aqueous Solution

Relaxivity in paramagnetic systems: Theory and mechanisms

Phosphinic derivative of DTPA conjugated to a G5 PAMAM dendrimer: an 17O and 1H relaxation study of its Gd(III) complex