Stephane Viel Dosy

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  • Principles and selected applications of Diffusion-Ordered NMR SpectroscopyStphane Viel, Ph. D.Assistant ProfessorAix-Marseille UniversityMolecular Sciences Institute II (UMR-6263)Chemometrics and Spectroscopy LaboratoryMarseilles (France)

  • DOSY ?Diffusion Ordered NMR SpectroscopyWeb of Science, 12 / 2007

  • DOSY ?Diffusion Ordered NMR SpectroscopyWeb of Science, 12 / 2007

  • NMR and DiffusionPGSEPulsed Gradient Spin Echo1965

  • NMR and DiffusionDOSYDiffusion Ordered SpectroscopY1992

  • NMR and DiffusionDOSYDiffusion Ordered SpectroscopY1992PGSEPulsed Gradient Spin Echo1965

  • General outlinePart 1: Theory about molecular mobility

    Self-diffusionStudy of self-diffusion by NMRPrinciples of Pulsed Gradient Spin Echo (PGSE)Diffusion ordered NMR spectroscopy (DOSY)

    Part 2: Selected applications of DOSY

  • Self-diffusionRandom translational motion of molecules or ions that arises from the thermal energy under conditions of thermodynamic equilibriumNo thermal gradient (convection)No concentration gradient (mutual diffusion)

  • Self-diffusion by Brown, 1828 Random jostling of molecules which leads to their net displacement over time

  • Self-diffusion coefficient DD is related to the hydrodynamic volume of the diffusing particle through

  • Self-diffusion coefficient DD is related to the hydrodynamic volume of the diffusing particle throughD self-diffusion coefficientk Boltzmanns constantT absolute temperaturef friction factorSphere

  • For a sphere diffusing in an isotropic and continuous medium of viscosity :Stokes Einstein equation

  • Pulsed Gradient Spin Echo (PGSE)Stejskal and Tanner, 1965Gradients of magnetic field (Pulsed)Study of self-diffusion by NMRGradientPulses

  • Study of self-diffusion by NMR1. Spatially label the nuclear spins using gradients of magnetic field.2. Monitor their displacement by measuring their spatial positions at 2 distinct times.Principle: 2 steps

  • Larmor frequencyIn NMR, each nuclear spin is identified by its Larmor precession frequency 0

  • Magnetic field gradientMagnetic field gradientFor a single and constant gradient oriented along the z direction

  • Magnetic field gradientMagnetic field gradientFor a single and constant gradient oriented along the z directionNotion of effective gradient

  • Phase shift of nuclear spinsAssume that the magnetic fieldgradient is active during a time A nuclear spin acquires a phase shift

  • Assume that the magnetic fieldgradient is active during a time Phase shift of nuclear spinsA nuclear spin acquires a phase shift

  • Phase shift of nuclear spinsAssume that the magnetic fieldgradient is active during a time A nuclear spin acquires a phase shift The spatial position of the nuclear spins is encoded into a phase shiftNuclear spin spatial labelling

  • Rotating frameIn NMR, a common simplification consists in describing the evolution of the magnetization in a frame rotating at the Larmor frequency 0For nuclear spins on resonance, the phase shift reduces to

  • Spin Echo or Hahn Echo (SE)Without magnetic field gradientsEcho

  • Spin Echo or Hahn Echo (SE)With magnetic field gradients

  • Spin Echo or Hahn Echo (SE)With magnetic field gradientsEcho

  • Spin Echo or Hahn Echo (SE)With magnetic field gradients

  • Spin Echo or Hahn Echo (SE)With magnetic field gradientsEcho

  • Spin Echo or Hahn Echo (SE)With magnetic field gradientsAttenuation factor

  • Iecho: Intensity at the echo with gradientsI0: Intensity at the echo without gradients D: Self-diffusion coefficient : gradient pulse duration : Diffusion time q: gradient pulse areaAttenuation factor

  • How do we actually obtain D? Attenuation factor

  • How do we actually obtain D? Attenuation factor

  • Stimulated Echo (STE)With magnetic field gradients

  • BPP-STE-LED sequenceStimulated Echo (STE) with Bipolar gradient (BPP) pulses and longitudinal eddy current delay (LED)

  • The BPP-STE-LED sequenceStimulated Echo (STE): T1 relaxation vs. T2 relaxationNo artefacts due to J modulationBipolar gradient pulses (BPP):Reduced eddy currentsLongitudinal Eddy currents Delay (LED):Less spectral distortions due to eddy currents

  • Stimulated Echo (STE) with Bipolar gradient (BPP) pulses and longitudinal eddy current delay (LED)The BPP-STE-LED sequence

  • The BPP-STE-LED sequenceStimulated Echo (STE): T1 relaxation vs. T2 relaxationNo artefacts due to J modulationBipolar gradient pulses (BPP):Reduced eddy currentsLongitudinal Eddy currents Delay (LED):Less spectral distortions due to eddy currents

  • Stimulated Echo (STE) with Bipolar gradient (BPP) pulses and longitudinal eddy current delay (LED)The BPP-STE-LED sequence

  • The BPP-STE-LED sequenceStimulated Echo (STE): T1 relaxation vs. T2 relaxationNo artefacts due to J modulationBipolar gradient pulses (BPP):Reduced eddy currentsLongitudinal Eddy currents Delay (LED):Less spectral distortions due to eddy currents

  • Stimulated Echo (STE) with Bipolar gradient (BPP) pulses and longitudinal eddy current delay (LED)The BPP-STE-LED sequenceEchoSignal

  • Stimulated Echo (STE) with Bipolar gradient (BPP) pulses and longitudinal eddy current delay (LED)SquenceBPP-STE-LED

  • How can we use PGSE data?NMR spectrum (frequency scale, ppm)DB

  • NMR spectrum (ppm scale)DBSIZEJames & McDonald, 1978Stilbs & Moseley, 1978-80

  • Size Resolved SpectrometryNMR spectrum (ppm scale)BCCStilbs, 1981

  • ppmDADCDBDHighLow

  • DADCDBDHighLow

  • Diffusion Ordered NMR SpectroscopYMorris & Johnson, 1992DOSYAntalek, B. Concepts in Magn. Reson 2002, 14, 225-258

  • DOSYDiffusion Ordered NMR SpectroscopYMorris & Johnson, 1992Signal processingMany processings available:- MaxEnt (Delsuc, M. A.)- DECRA (Antalek, B.)- CORE (Stilbs, P.)- MCR (van Gorkom, L. C. M.)- MULVADO (Huo, R.)- iRRT (Mandelstham, V.)

  • DOSYDiffusion Ordered NMR SpectroscopYMorris & Johnson, 1992Signal processingMany processings available:- MaxEnt (Delsuc, M. A.)- DECRA (Antalek, B.)- CORE (Stilbs, P.)- MCR (van Gorkom, L. C. M.)- MULVADO (Huo, R.)- iRRT (Mandelstham, V.)

  • DOSY mapAdapted from Nilsson et al.

  • Distortions due to spectral overlapAdapted from Nilsson et al.

  • iRRT

    inverseRegularized ResolventTransformMixture of 2 isomersV. MandelshtamA. J. ShakaThureau, P.; Thvand, A.; Ancian, B.; Escavabaja, P.; Armstrong, G. S.; Mandelshtam, V. A., ChemPhysChem 2005, 6, 1Armstrong, G. S.; Loening, N. M.; Curtis, J. E.; Shaka, A. J.; Mandelshtam, V. A., J. Magn. Reson. 2003, 163, 139

  • Part 1: Theory about molecular mobility

    Self-diffusionStudy of self-diffusion by NMRPrinciples of Pulsed Gradient Spin Echo (PGSE)Diffusion ordered NMR spectroscopy (DOSY)

    Part 2: Selected applications of DOSY General outline

  • Chiral recognitionChiral recognition of dipeptides in a biomembrane modelC. Bombelli, S. Borocci, F. Lupi, G. Mancini, L. Mannina, A. L. Segre, S. VielJ. Am. Chem. Soc. 2004, 126, 13354-13362

  • Introduction The organization of biomembranes is based on molecular recognition phenomena (chiral recognition) To investigate the non covalent interactions involved in such systems, models are usedC. Bombelli, S. Borocci, F. Lupi, G. Mancini, L. Mannina, A. L. Segre, S. VielJ. Am. Chem. Soc. 2004, 126, 13354-13362we used Sodium N-doceanoyl-L-prolinate (SDP)Here

  • Introduction (2)We studied by NMR the chiral recognition in SDP micelles of 2 dipeptidesNMR techniques: 1H, PGSE, ROESY+Molecular mechanic calculationsC. Bombelli, S. Borocci, F. Lupi, G. Mancini, L. Mannina, A. L. Segre, S. VielJ. Am. Chem. Soc. 2004, 126, 13354-13362

  • 1H experiments: LL/DD coupleDitryptophan (1)+SDP micellesDiphenylalanine (2)+SDP micellesC. Bombelli, S. Borocci, F. Lupi, G. Mancini, L. Mannina, A. L. Segre, S. VielJ. Am. Chem. Soc. 2004, 126, 13354-13362

  • 1H experiments: LD/DL coupleDitryptophan (1)+SDP micellesDiphenylalanine (2)+SDP micellesC. Bombelli, S. Borocci, F. Lupi, G. Mancini, L. Mannina, A. L. Segre, S. VielJ. Am. Chem. Soc. 2004, 126, 13354-13362

  • PGSE experiments Monitor the D values of the dipeptides by PGSE experiments 2-site model: dipeptide in equilibrium between the bound (b) and free (f) phase+FreeStateBoundStateC. Bombelli, S. Borocci, F. Lupi, G. Mancini, L. Mannina, A. L. Segre, S. VielJ. Am. Chem. Soc. 2004, 126, 13354-13362

  • PGSE experiments Monitor the D values of the dipeptides by PGSE experiments 2-site model: dipeptide in equilibrium between the bound (b) and free (f) phase+C. Bombelli, S. Borocci, F. Lupi, G. Mancini, L. Mannina, A. L. Segre, S. VielJ. Am. Chem. Soc. 2004, 126, 13354-13362

  • PGSE experimentsDetermine the partition coefficient of the dipeptides in the 2 phasesC. Bombelli, S. Borocci, F. Lupi, G. Mancini, L. Mannina, A. L. Segre, S. VielJ. Am. Chem. Soc. 2004, 126, 13354-13362

  • PGSE experimentsBound molar fractions xb and partition coefficients pC. Bombelli, S. Borocci, F. Lupi, G. Mancini, L. Mannina, A. L. Segre, S. VielJ. Am. Chem. Soc. 2004, 126, 13354-13362

  • PGSE experimentsBound molar fractions xb and partition coefficients pC. Bombelli, S. Borocci, F. Lupi, G. Mancini, L. Mannina, A. L. Segre, S. VielJ. Am. Chem. Soc. 2004, 126, 13354-13362

  • PGSE experimentsBound molar fractions xb and partition coefficients pC. Bombelli, S. Borocci, F. Lupi, G. Mancini, L. Mannina, A. L. Segre, S. VielJ. Am. Chem. Soc.

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