Lothar Helm
EPFL SB-DO
BCH 4104 (Batochime UNIL)
Av. F.-A. Forel 2
CH-1015 Lausanne
Unité: ISIC-DIV
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 2004 - 2014
A. Babič; V. Vorobiev; C. Xayaphoummine; G. Lapicorey; A.-S. Chauvin et al. : Self-Assembled Nanomicelles as MRI Blood-Pool Contrast Agent; Chemistry - A European Journal. 2017. DOI : 10.1002/chem.201703962.
B. Mousavi; A.-S. Chauvin; L. Moriggi; L. Helm : Carbazole as Linker for Dinuclear Gadolinium-Based MRI Contrast Agents; European Journal Of Inorganic Chemistry. 2017. DOI : 10.1002/ejic.201700847.
J. Gamrekelashvili; R. Giagnorio; J. Jussofie; O. Soehnlein; J. Duchene et al. : Regulation of monocyte cell fate by blood vessels mediated by Notch signalling; Nature Communications. 2016. DOI : 10.1038/ncomms12597.
C. Gonzales; H. A. I. Yoshihara; N. Dilek; J. Leignadier; M. Irving et al. : In-Vivo Detection and Tracking of T Cells in Various Organs in a Melanoma Tumor Model by F-19-Fluorine MRS/MRI; Plos One. 2016. DOI : 10.1371/journal.pone.0164557.
D. Mammoli; E. Canet; R. Buratto; P. Mieville; L. Helm et al. : Collisional cross-section of water molecules in vapour studied by means of H-1 relaxation in NMR; Scientific Reports. 2016. DOI : 10.1038/srep38492.
C. Platas-Iglesias; D. Esteban-Gomez; L. Helm; M. Regueiro-Figueroa : Transient versus Static Electron Spin Relaxation in Mn2+ Complexes Relevant as MRI Contrast Agents; Journal Of Physical Chemistry A. 2016. DOI : 10.1021/acs.jpca.6b05423.
S. Karimi; L. Tei; M. Botta; L. Helm : Evaluation of Water Exchange Kinetics on [Ln(AAZTAPh–NO2)(H2O)q]x Complexes Using Proton Nuclear Magnetic Resonance; Inorganic Chemistry. 2016. DOI : 10.1021/acs.inorgchem.6b00976.
S. Karimi; G. Hunter; L. Moriggi; C. Platas-Iglesias; L. Helm : Complexation of [Gd(DTTA–Me)(H2O)2]− by Fluoride and Its Consequences to Water Exchange; Inorganic Chemistry. 2016. DOI : 10.1021/acs.inorgchem.6b00861.
S. Karimi; L. Helm : Water Exchange on [Ln(DO3A)(H2O)2] and [Ln(DTTA–Me)(H2O)2]− Studied by Variable Temperature, Pressure, and Magnetic Field NMR; Inorganic Chemistry. 2016. DOI : 10.1021/acs.inorgchem.6b00363.
A. Fontes; S. Karimi; L. Helm; P. M. Ferreira; J. P. Andre : PEGylated DOTA-AHA-Based Gd-III Chelates: A Relaxometric Study; European Journal Of Inorganic Chemistry. 2015. DOI : 10.1002/ejic.201500688.
C. S. Bonnet; S. Laine; F. Buron; G. Tircso; A. Pallier et al. : A Pyridine-Based Ligand with Two Hydrazine Functions for Lanthanide Chelation: Remarkable Kinetic Inertness for a Linear, Bishydrated Complex; Inorganic Chemistry. 2015. DOI : 10.1021/acs.inorgchem.5b00804.
É. Tóth; L. Helm; A. Merbach : Metal Complexes as MRI Contrast Enhancement Agents; Reference Module in Chemistry, Molecular Sciences and Chemical Engineering; Elsevier, 2015.
A. Fontes; S. Karimi; L. Helm; M. Yulikov; P. M. Ferreira et al. : Dinuclear DOTA-Based Gd-III Chelates - Revisiting a Straightforward Strategy for Relaxivity Improvement; European Journal Of Inorganic Chemistry. 2015. DOI : 10.1002/ejic.201403159.
W. Zhang; J. A. Peters; F. Mayer; L. Helm; K. Djanashvili : Prototropic Exchange Governs T-1 and T-2 Relaxivities of a Potential MRI Contrast Agent Nanozeolite Gd-LTL with a High pH Responsiveness; Journal Of Physical Chemistry C. 2015. DOI : 10.1021/jp510656d.
M. F. Ferreira; J. Goncalves; B. Mousavi; M. I. M. Prata; S. P. J. Rodrigues et al. : Gold nanoparticles functionalised with fast water exchanging Gd3+ chelates: linker effects on the relaxivity; Dalton Transactions. 2015. DOI : 10.1039/c4dt03210a.
G. Bodizs; L. Helm : Solvent Exchange and Electron-Spin Relaxation on Homoleptic Acetonitrile Complexes of Trivalent Lanthanides; Inorganic Chemistry. 2015. DOI : 10.1021/ic5028493.
E. Boros; S. Karimi; N. Kenton; L. Helm; P. Caravan : Gd(DOTAlaP): Exploring the Boundaries of Fast Water Exchange in Gadolinium-Based Magnetic Resonance Imaging Contrast Agents; Inorganic Chemistry. 2014. DOI : 10.1021/ic5008928.
H. Jaccard; P. Mieville; C. Cannizzo; C. R. Mayer; L. Helm : Dynamic aggregation of the mid-sized gadolinium complex {Ph-4[Gd(DTTA)(H2O)(2)](-)(3)}; Journal of Biological Inorganic Chemistry. 2014. DOI : 10.1007/s00775-013-1036-y.
E. Toth; L. Helm; A. Merbach : Relaxivity of gadolinium(III) complexes: theory and mechanism; Chemistry of Contrast Agents in Medical Magnetic Resonance Imaging (2nd Edition); Chichester: John Wiley & Sons Ltd, 2013. p. 25-81.
The Chemistry of Contrast Agents in Medical Magnetic Resonance Imaging ; Chichester, UK: John Wiley & Sons Ltd..
P. V. Grundler; J. Brugger; B. E. Etschmann; L. Helm; W. Liu et al. : Speciation of aqueous tellurium(IV) in hydrothermal solutions and vapors, and the role of oxidized tellurium species in Te transport and gold deposition; Geochimica Et Cosmochimica Acta. 2013. DOI : 10.1016/j.gca.2013.06.009.
G. A. Rolla; C. Platas-Iglesias; M. Botta; L. Tei; L. Helm : H-1 and O-17 NMR Relaxometric and Computational Study on Macrocyclic Mn(II) Complexes; Inorganic Chemistry. 2013. DOI : 10.1021/ic302785m.
Z. Kotkova; L. Helm; J. Kotek; P. Hermann; I. Lukes : Gadolinium complexes of monophosphinic acid DOTA derivatives conjugated to cyclodextrin scaffolds: efficient MRI contrast agents for higher magnetic fields; Dalton Transactions. 2012. DOI : 10.1039/c2dt30858d.
D. Esteban-Gomez; A. De Blas; T. Rodriguez-Blas; L. Helm; C. Platas-Iglesias : Hyperfine Coupling Constants on Inner-Sphere Water Molecules of Gd-III-Based MRI Contrast Agents; Chemphyschem. 2012. DOI : 10.1002/cphc.201200417.
G. Bodizs; L. Helm : NMR and Electron Paramagnetic Resonance Studies of [Gd(CH3CN)(9)](3+) and [Eu(CH3CN)(9)](2+): Solvation and Solvent Exchange Dynamics in Anhydrous Acetonitrile; Inorganic Chemistry. 2012. DOI : 10.1021/ic300478c.
A. M. Nonat; C. Gateau; P. H. Fries; L. Helm; M. Mazzanti : New Bisaqua Picolinate-Based Gadolinium Complexes as MRI Contrast Agents with Substantial High-Field Relaxivities; European Journal Of Inorganic Chemistry. 2012. DOI : 10.1002/ejic.201101162.
L. Moriggi; M. A. Yaseen; L. Helm; P. Caravan : Serum Albumin Targeted, pH-Dependent Magnetic Resonance Relaxation Agents; Chemistry-A European Journal. 2012. DOI : 10.1002/chem.201103344.
F. Caillé; C. S. Bonnet; F. Buron; S. Villette; L. Helm et al. : Isoquinoline-Based Lanthanide Complexes: Bright NIR Optical Probes and Efficient MRI Agents; Inorganic Chemistry. 2012. DOI : 10.1021/ic202446e.
C. S. Bonnet; F. Buron; F. Caille; C. M. Shade; B. Drahos et al. : Pyridine-Based Lanthanide Complexes Combining MRI and NIR Luminescence Activities; Chemistry-A European Journal. 2012. DOI : 10.1002/chem.201102310.
F. Mayer; C. Platas-Iglesias; L. Helm; J. A. Peters; K. Djanashvili : O-17 NMR and Density Functional Theory Study of the Dynamics of the Carboxylate Groups in DOTA Complexes of Lanthanides in Aqueous Solution; Inorganic Chemistry. 2012. DOI : 10.1021/ic201393n.
F. Senn; L. Helm; A. Borel; C. A. Daul : Electronic fine structure calculation of [Gd(DOTA)(H2O)]- using LF-DFT: The zero field splitting; Comptes Rendus Chimie. 2012. DOI : 10.1016/j.crci.2011.10.008.
B. Drahoš; J. Kotek; I. Cı́Sařová; P. Hermann; L. Helm et al. : Mn2+ Complexes with 12-Membered Pyridine Based Macrocycles Bearing Carboxylate or Phosphonate Pendant Arm: Crystallographic, Thermodynamic, Kinetic, Redox, and 1H/17O Relaxation Studies; Inorganic Chemistry. 2011. DOI : 10.1021/ic201935r.
L. Helm : The challenge of T1 contrast agents for high-magnetic field MRI; Chimia -Zurich-. 2011. DOI : 10.2533/chimia.2011.696.
E. Tóth; L. Helm : Gadolinium-Based Bionanomaterials for Magnetic Resonance Imaging; Nanobiomaterials Handbook; Boca Raton: CRC Press, 2011. p. 18/1-18/34.
G. Novitchi; L. Helm; C. Anson; A. K. Powell; A. Merbach : 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; Inorganic Chemistry -American Chemical Society-. 2011. DOI : 10.1021/ic201484q.
P. Miéville; H. Jaccard; F. Reviriego; R. Tripier; L. Helm : Synthesis, complexation and NMR relaxation properties of Gd3+ complexes of Mes(DO3A)3; Dalton Transactions. 2011. DOI : 10.1039/c0dt01597k.
P. Miéville; S. Jannin; L. Helm; G. Bodenhausen : NMR of Insensitive Nuclei Enhanced by Dynamic Nuclear Polarization; CHIMIA International Journal for Chemistry. 2011. DOI : 10.2533/chimia.2011.260.
F. Riblet; G. Novitchi; R. Scopelliti; L. Helm; A. Gulea et al. : Isomerization Mechanisms of Stereolabile tris- and bis-Bidentate Octahedral Cobalt(II) Complexes: X-ray Structure and Variable Temperature and Pressure NMR Kinetic Investigation; Inorganic Chemistry -American Chemical Society-. 2010. DOI : 10.1021/ic902494j.
J. S. Ananta; B. Godin; R. Sethi; L. Moriggi; X. Liu et al. : Geometrical confinement of gadolinium-based contrast agents in nanoporous particles enhances T1 contrast; Nature Nanotechnology. 2010. DOI : 10.1038/NNANO.2010.203.
P. Miéville; S. Jannin; L. Helm; G. Bodenhausen : Kinetics of Yttrium-Ligand Complexation Monitored Using Hyperpolarized 89Y as a Model for Gadolinium in Contrast Agents; Journal of the American Chemical Society. 2010. DOI : 10.1021/ja1013954.
L. Helm : Optimization of gadolinium-based MRI contrast agents for high magnetic‑field applications; Future Med. Chem.. 2010. DOI : 10.4155/FMC.09.174.
A. Nonat; M. Giraud; C. Gateau; P. H. Fries; L. Helm et al. : Gadolinium(III) complexes of 1,4,7-triazacyclononane based picolinate ligands: simultaneous optimization of water exchange kinetics and electronic relaxation; Dalton Transactions. 2009. DOI : 10.1039/b907738c.
M. Benmelouka; J. Van Tol; A. Borel; S. Nellutla; M. Port et al. : Multiple Frequency and Variable Temperature EPR study of Gd(III) polyaminocarboxylates: analysis and comparison of the magnetically dilute powder and the frozen solution spectra; Helvetica Chimica Acta. 2009. DOI : 10.1002/hlca.200900117.
L. Moriggi; C. Cannizzo; E. Dumas; C. R. Mayer; A. Ulianov et al. : Gold Nanoparticles Functionalized with Gadolinium Chelates as High-Relaxivity MRI Contrast Agents; Journal of the American Chemical Society. 2009. DOI : 10.1021/ja904094t.
S. Silvério; S. Torres; A. F. Martins; J. A. Martins; J. P. André et al. : Lanthanide chelates of (bis)-hydroxymethyl-substituted DTTA with potential application as contrast agents in magnetic resonance imaging; Dalton Trans.. 2009. DOI : 10.1039/b823402g.
G. Bodizs; I. Raabe; R. Scopelliti; I. Krossing; L. Helm : Synthesis, structures and characterisations of truly homoleptic acetonitrile Ln3+ complexes in solid state and in solution; Dalton Trans.. 2009. DOI : 10.1039/b822322j.
L. Moriggi; A. Aebischer; C. Cannizzo; A. Sour; A. Borel et al. : A ruthenium-based metallostar: synthesis, sensitized luminescence and 1H relaxivity; Dalton Transactions. 2009. DOI : 10.1039/b818599a.
G. Novitchi; F. Riblet; R. Scopelliti; L. Helm; A. Gulea et al. : Mechanism of Pyridine-Ligand Exchanges at the Different Labile Sites of 3d Heterometallic and Mixed Valence μ3-oxo Trinuclear Clusters; Inorganic Chemistry. 2008. DOI : 10.1021/ic801206m.
O. V. Yazyev; L. Helm : Nuclear Spin Relaxation Parameters of MRI Contrast Agents – Insight from Quantum Mechanical Calculations; European Journal of Inorganic Chemistry. 2008.
L. Helm : Ligand exchange and complex formation kinetics studied by NMR exemplified on fac-[(CO)3M(H2O)]+ (M = Mn, Tc, Re); Coordination Chemistry Reviews. 2008. DOI : 10.1016/j.ccr.2008.01.009.
P. L. de Sousa; J. B. Livramento; L. Helm; A. E. Merbach; W. Même et al. : In vivo MRI assessment of a novel GdIII-based contrast agent designed for high magnetic field applications; Contrast Media Mol. Imaging. 2008. DOI : 10.1002/cmmi.233.
L. Moriggi; C. Cannizzo; C. Prestinari; F. Berrière; L. Helm : Physicochemical Properties of the High-Field MRI-Relevant [Gd(DTTA-Me)(H2O)2]− Complex; Inorganic Chemistry. 2008. DOI : 10.1021/ic800512k.
A. Keelara; H. Jaccard; M. Kretzschmar; L. Helm; H. R. Maecke : Novel DOTA-based prochelator for divalent peptide vectorization: synthesis of dimeric bombesin analogues for multimodality tumor imaging and therapy; Chemical Communications. 2008. DOI : 10.1039/b805281f.
E. Belorizky; P. H. Fries; L. Helm; J. Kowalewski; D. Kruk et al. : Comparison of different methods for calculating the paramagnetic relaxation enhancement of nuclear spins as a function of the magnetic field; Journal of Chemical Physics. 2008. DOI : 10.1063/1.2833957.
S. Torres; M. I. M. Prata; A. C. Santos; J. P. André; J. A. Martins et al. : Gd(III)-EPTPAC16, a new self-assembling potential liver MRI contrast agent: in vitro characterization and in vivo animal imaging studies; NMR in Biomedicine. 2008. DOI : 10.1002/nbm.1194.
J. B. Livramento; L. Helm; A. Sour; C. O’neil; A. E. Merbach et al. : A benzene-core trinuclear GdIII complex: towards the optimization of relaxivity for MRI contrast agent applications at high magnetic field; Dalton Trans.. 2008. DOI : 10.1039/b717390c.
K. B. Hartman; S. Laus; R. D. Bolskar; R. Muthupillai; L. Helm et al. : Gadonanotubes as Ultrasensitive pH-Smart Probes for Magnetic Resonance Imaging; Nano Letters. 2008. DOI : 10.1021/nl0720408.
A. Borel; J. F. Bean; R. B. Clarkson; L. Helm; L. Moriggi et al. : Towards the Rational Design of MRI Contrast Agents: Electron Spin Relaxation Is Largely Unaffected by the Coordination Geometry of Gadolinium(III)-DOTA-Type Complexes; Chemistry - A European Journal. 2008. DOI : 10.1002/chem.200701747.
S. Torres; J. A. Martins; J. P. André; G. A. Pereira; R. Kiraly et al. : H5EPTPACH2OH: Synthesis, Relaxometric Characterization and 1H NMR Spectroscopic Studies on the Solution Dynamics of Its LnIII Complexes; European Journal of Inorganic Chemistry. 2007. DOI : 10.1002/ejic.200700435.
O. V. Yazyev; L. Helm : Magnetism induced by single-atom defects in nanographites; Journal of Physics: Conference Series. 2007. DOI : 10.1088/1742-6596/61/1/255.
O. V. Yazyev; L. Helm : Gadolinium(III) ion in liquid water: structure, dynamics and magnetic interactions from first principles; Journal of Chemical Physics. 2007. DOI : 10.1063/1.2759919.
A. Borel; S. Laus; A. Ozarowski; C. Gateau; A. Nonat et al. : Multiple-frequency EPR spectra of two aqueous Gd3+ polyaminopolypyridinecarboxylate complexes: a study of high field effects; Journal of Physical Chemistry A. 2007. DOI : 10.1021/jp066921z.
Z. Jászberényi; L. Moriggi; P. Schmidt; C. Weidensteiner; R. Kneuer et al. : Physicochemical and MRI characterization of Gd3+-loaded polyamidoamine and hyperbranched dendrimers; Journal of Biological Inorganic Chemistry. 2007. DOI : 10.1007/s00775-006-0197-3.
S. Laus; B. Sitharaman; E. Tóth; R. D. Bolskar; L. Helm et al. : Understanding Paramagnetic Relaxation Phenomena for Water-Soluble Gadofullerenes; Journal of Physical Chemistry C. 2007. DOI : 10.1021/jp070458o.
O. V. Yazyev; I. Tavernelli; U. Rothlisberger; L. Helm : Early stages of radiation damage in graphite and carbon nanostructures: A first-principles molecular dynamics study; Physical Review B. 2007. DOI : 10.1103/PhysRevB.75.115418.
O. V. Yazyev; L. Helm : Defect-induced magnetism in graphene; Physical Review B. 2007.
P. Lebduskova; P. Hermann; L. Helm; E. Tóth; J. Kotek et al. : Gadolinium(III) complexes of mono-and diethyl esters of monophosphinic acid analogue of DOTA as potential MRI contrast agents: solution structures and relaxometric studies; Dalton Transactions. 2007.
M. Benmelouka; A. Borel; L. Moriggi; L. Helm; A. E. Merbach : 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; Journal of Physical Chemistry B. 2007. DOI : 10.1021/jp0633289.
P. V. Grundler; O. V. Yazyev; N. Aebischer; L. Helm; G. Laurenczy et al. : Kinetic studies on the first dihydrogen aquacomplex, [Ru(H2)(H2O)5]2+: Formation under H2 pressure and catalytic H/D isotope exchange in water; Inorganica Chimica Acta. 2006. DOI : 10.1016/j.ica.2005.06.056.
P. V. Grundler; L. Helm; R. Alberto; A. E. Merbach : Relevance of the Ligand Exchange Rate and Mechanism of fac-[(CO)3M(H2O)3]+ (M = Mn, Tc, Re) Complexes for New Radiopharmaceuticals; Inorganic Chemistry. 2006. DOI : 10.1021/ic061578y.
J. Costa; E. Balogh; V. Turcry; R. Tripier; M. Le Bacon et al. : Unexpected Aggregation of Neutral, Xylene-Cored Dinuclear GdIII Chelates in Aqueous Solution; Chem.-Eur. J.. 2006. DOI : 10.1002/chem.200501335.
L. Helm : Relaxivity in paramagnetic systems: Theory and mechanisms; Prog. NMR Spectrosc.. 2006.
P. Lebduskova; A. Sour; L. Helm; E. Toth; J. Kotek et al. : Phosphinic derivative of DTPA conjugated to a G5 PAMAM dendrimer: an 17O and 1H relaxation study of its Gd(III) complex; Dalton Transactions. 2006. DOI : 10.1039/b517847a.
O. Yazyev; L. Helm : Hyperfine interactions in aqueous solution of Cr3+: an ab initio molecular dynamics study; Theoretical Chemistry Accounts. 2006. DOI : 10.1007/s00214-005-0052-6.
M.-L. Lehaire; P. V. Grundler; S. Steinhauser; N. Marti; L. Helm et al. : Water-Exchange Study Revealed Unexpected Substitution Behavior of [(CO)2(NO)Re(H2O)3]2+ in Aqueous Media; Inorganic Chemistry. 2006. DOI : 10.1021/ic060010m.
J. B. Livramento; C. Weidensteiner; M. I. M. Prata; P. R. Allegrinin; C. F. G. C. Geraldes et al. : First in vivo MRI assessment of a self-assembled metallostar compound endowed with a remarkable high field relaxivity; Contrast Media & Molecular Imaging. 2006. DOI : 10.1002/cmmi.92.
F. Riblet; G. Novichi; L. Helm; A. Gulea; A. E. Merbach : Isomerization mechanisms of a labile Co(II) octahedral complex; Chimia. 2006. DOI : 10.2533/000942906777674769.
O. Yazyev; L. Helm : 17O nuclear quadrupole coupling constants of water bound to a metal ion: A gadolinium(III) case study; Journal of Chemical Physics. 2006. DOI : 10.1063/1.2217950.
M. Benmelouka; J. Van Tol; A. Borel; M. Port; L. Helm et al. : A High-Frequency EPR Study of Frozen Solutions of Gd(III) Complexes: Straightforward Determination of the Zero-Field Splitting Parameters and Simulation of the NMRD Profiles; Journal of the American Chemical Society. 2006. DOI : 10.1021/ja0583261.
L. Burai; É. Tóth; H. Bazin; M. Benmelouka; Z. Jászberényi et al. : Positively Charged GdIII Cryptates: Slow, Associative Water Exchange; Dalton Transactions. 2006. DOI : 10.1039/b506700f.
J. Costa; E. Toth; L. Helm; A. E. Merbach : Dinuclear, Bishydrated GdIII Polyaminocarboxylates with a Rigid Xylene Core Display Remarkable Proton Relaxivities; Inorganic Chemistry. 2005. DOI : 10.1021/ic0500309.
L. Helm; A. E. Merbach : Inorganic and Bioinorganic Solvent Exchange Mechanisms; Chemical Reviews. 2005. DOI : 10.1021/cr030726o.
J. Costa; R. Ruloff; L. Burai; L. Helm; A. E. Merbach : Rigid M(II)L2Gd(III)2 (M=Fe, Ru) Complexes of a Terpyridine-Based Heteroditopic Chelate: A Class of Candidates for MRI Contrast Agents; Journal of the American Chemical Society. 2005. DOI : 10.1021/ja0424169.
L. Helm; G. Nicolle; A. E. Merbach : Water and proton Exchange Processes on Metal Ions; Adv. Inorg. Chem.. 2005. DOI : 10.1016/S0898-8838(05)57007-7.
N. Chatterton; C. Gateau; M. Mazzanti; J. Pécaut; A. Borel et al. : The effect of pyridinecarboxylate chelating groups on the stability and electronic relaxation of gadolinium complexes; Dalton Transactions. 2005. DOI : 10.1039/b416150e.
É. Tóth; R. D. Bolskar; A. Borel; G. González; L. Helm et al. : Water-Soluble Gadofullerenes: Toward High-Relaxivity, pH-Responsive MRI Contrast Agents; Journal of the American Chemical Society. 2005. DOI : 10.1021/ja044688h.
O. V. Yazyev; I. Tavernelli; L. Helm; U. Rothlisberger : Core spin-polarization correction in pseudopotential-based electronic structure calculations; Physical Review B. 2005.
O. V. Yazyev; L. Helm : Isotropic Knight shift of metallic carbon nanotubes; Physical Review B. 2005.
O. V. Yazyev; L. Helm; V. G. Malkin; O. L. Malkina : Quantum Chemical Investigation of Hyperfine Coupling Constants on First Coordination Sphere Water Molecule of Gadolinium(III) Aqua Complexes; Journal of Physical Chemistry A. 2005. DOI : 10.1021/jp053825+.
B. Sitharaman; K. R. Kissell; K. B. Hartman; L. A. Tran; A. Baikalov et al. : Superparamagnetic gadonanotubes are high-performance MRI contrast agents; Chemical Communications. 2005.
S. Laus; B. Sitharaman; E. Toth; R. D. Bolskar; L. Helm et al. : Destroying gadofullerene aggregates by salt addition in aqueous solution of Gd@C60(OH)x and Gd@C60[C(COOH2)]10; Journal of the American Chemical Society. 2005. DOI : 10.1021/ja052388+.
V. Stavila; A. Gulea; S. Shova; Y. A. Simonov; P. Petrenko et al. : An unexpected influence of the nature of the amine on the crystal structure of some Co(III)-Bi(III) heterobimetallic complexes; Inorganica Chimica Acta. 2004. DOI : 10.1016/j.ica.2004.01.025.
A. Borel; L. Helm; C. A. E. Daul : Hybrid ligand-field theory/quantum chemical calculation of the fine structure and ZFS in lanthanide(III) complexes; Chemical Physics Letters. 2004. DOI : 10.1016/j.cplett.2003.11.082.
G. Novitchi; F. Riblet; L. Helm; R. Scopelliti; A. Gulea et al. : Richness of isomerism in labile octahedral Werner-type cobalt(II) complexes demonstrated by 19F NMR spectroscopy: Structure and stability; Magnetic Resonance in Chemistry. 2004. DOI : 10.1002/mrc.1438.
R. Dessapt; L. Helm; A. E. Merbach : DMSO exchange on [Gd(DMSO)8]3+ - a variable pressure 17O NMR study; Journal of Physics : Condensed Matter. 2004. DOI : 10.1088/0953-8984/16/14/012.
A. Borel; F. Yerly; L. Helm; A. E. Merbach : Molecular dynamics simulations of the internal mobility of Gd3+-based MRI contrast agents: consequences for water proton relaxivity; Chimia. 2004. DOI : 10.2533/000942904777678055.
A. Borel; L. Helm; A. E. Merbach : Molecular dynamics of Gd(III) complexes in aqueous solution by HF EPR; Very High Frequency (VHF) ESR/EPR; New York: Plenum Press, 2004. p. 207-247.
