Laura Castañar receives award at ENC 2015

Laura CastañarAward to Laura Castañar at the 56th ENC held in Asilomar from 19th to 24th April 2015. was honoured at the 56th Experimental Nuclear Magnetic Resonance Conference (ENC) with the Ritchey Travel Award for her Ph.D. Thesis research on “Development and application of modern pure shift NMR techniques and improved HSQC/HSQMBC experiments”The award ceremony took place at the After-Dinner Program in Asilomar Conference Center in Pacific Grove, California, USA, the 23th April, 2015.

The ENC Ritchey Travel Award to advanced Ph.D. students was established to honor William M. Ritchey, who was Professor Emeritus of Chemistry and Macromolecular Science at Case Western Reserve University and founder of the ENC. Professor William Ritchey founded the ENC in 1960 when he organized a rather informal meeting to discuss experimental problems with early nmr spectrometer and «we decided to meet again the next year and possibly a few more times and to keep our focus on experimental aspects of NMR.» The areas of the Award are to reflect Professor Ritchey’s broad interests in the development and application of NMR to chemical and material sciences.

As part of the award, Laura gave the oral presentation entitled “HOBS: Broadband Homonuclear Decoupled Band-Selective NMR Experiments with Full Sensitivity” in which she explained a novel NMR approach for recording broadband HOmodecoupled Band-Selective (HOBS) NMR spectra with full sensitivity. The HOBS technique allows recording fully homodecoupled singlet signals from chosen parts of the 1H spectrum without loss of sensitivity.

Saurí, a former Ph.D. student at SeRMN currently pursuing a postdoc at Merck Research Laboratories.
Laura shows her diploma of the ENC Ritchey Travel Award. Next to her is Josep Saurí, a former Ph.D. student at SeRMN currently working as postdoc researcher at Merck Research Laboratories.

She also described the straightforward implementation of the HOBS technique for a number of homo and heteronuclear multidimensional experiments (e.g. HOBS-TOCSY, HOBS-HSQC, HOBS-HSQMBC, and more) and she demonstrated that this technique had an ample range of practical applications like the direct measurement of nJCH, the determination of T1 and T2 NMR relaxation times, and enantiodifferentiation studies, among other.

Laura has been working as a Ph.D. candidate at the Department of Chemistry and SeRMN under the co-direction of Dr. Albert Virgili and Dr. Teodor Parella since Sept 2012, when she enrolled in the Department of Chemistry doctoral program at Universitat Autònoma de Barcelona with a fellowship from UAB. She is currently in her third year and expects to defend the doctoral thesis before the summer holiday. You can read about her work on this blog.

Review – Pure shift NMR experiments: recent developments, methods and applications

MRC_teo copy“Broadband 1H homodecoupled NMR experiments: recent developments, methods and applications” by Laura Castañar and Teodor Parella. Magnetic Resonance in Chemistry, 2015. DOI: 10.1002/mrc.4238

In recent years, a great interest in the development of new broadband 1H homonuclear decoupled techniques providing simplified JHH multiplet patterns has emerged again in the field of small molecule NMR. The resulting highly resolved 1H NMR spectra display resonances as collapsed singlets, therefore minimizing signal overlap and expediting spectral analysis. This review aims at presenting the most recent advances in pure shift NMR spectroscopy, with a particular emphasis to the Zangger–Sterk experiment. A detailed discussion about the most relevant practical aspects in terms of pulse sequence design, selectivity, sensitivity, spectral resolution and performance is provided. Finally, the implementation of the different reported strategies into traditional 1D and 2D NMR experiments is described while several practical applications are also reviewed.

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Ultra high-resolution HSQC

SeRMN seminar

  • Date:  Thursday 7th May, 2015
  • Hour: 15:30
  • Location:  SeRMN,  Facultats de Ciències i Biociències, C2/-135
  • Speaker:  Núria Marcó, SeRMN PhD Student

The content of our recently published article entitled “Ultra high-resolution HSQC: Application to the efficient and accurate measurement of heteronuclear coupling constants” will be explained and discussed briefly. A rapid NMR data acquisition strategy in terms of enhanced resolution per time unit for the simple and efficient determination of multiple coupling constants is described. The use of 13C spectral aliasing combined with broadband 1H homodecoupling allows accurate measurements from ultra high resolved 2D HSQC cross-peaks.

Ultra HIgh Resolved HSQCportada

SeRMN presentation at the 56th ENC 2015 Conference

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During these days takes place the 56th Experimental Nuclear Magnetic Resonance Conference (ENC) in Asilomar Conference Grounds (Pacific Grove, California, USA) where Laura Castañar presents an Oral Communication entitled “HOBS: Broadband Homonuclear Decoupled Band-Selective NMR Experiments with Full Sensitivity”

Abstract: Recently, a novel NMR approach for recording broadband HOmodecoupled Band-Selective (HOBS) NMR spectra with full sensitivity has been reported. The HOBS technique is a frequency-selective experiment which affords fully homodecoupled singlet signals in particular areas of the 1H spectrum without sacrificing sensitivity, allowing the fast NMR data acquisition in the same experimental times as regular experiments. Here we present the easy and reliable implementation of the HOBS technique for a number of homo and heteronuclear multidimensional experiments, such as HOBS-TOCSY, HOBS-HSQC, HOBS-HSQMBC, HOBS Inversion-Recovery and HOBS-CPMG-PROJECT. In addition, its practical utility in a wide range of applications, covering the direct measurement of nJCH, the determination of T1 and T2 NMR relaxation times and the enantiodifferentiation studies, among other.

ENC2015_TOC_ Laura Castañar

NMR-Aided Differentiation of Enantiomers: Signal Enantioresolution

15ACA“NMR-Aided Differentiation of Enantiomers: Signal Enantioresolution” by Míriam Pérez-Trujillo, Teodor Parella and Lars T. Kuhn. Analytica Chimica Acta, 2015. DOI: 10.1016/j.aca.2015.02.069

NMR-aided enantiodiscrimination using chiral auxiliaries (CAs) is a recognized method for differentiating enantiomers and for measuring enantiomeric ratios (er). Up to the present, the study, optimization, and comparison of such methods have been performed based on the enantiodifferentiation of NMR signals via analysing non-equivalent chemical-shift values (ΔΔδ) of the diastereoisomeric species formed. However, a poor and non-reliable comparison of results is often obtained via the analysis of ΔΔδ exclusively. In here, the concept of enantioresolution of an individual NMR signal and its importance for NMR-aided enantiodifferentiation studies is introduced and discussed. In addition, the enantioresolution quotient, E, is proposed as the parameter to describe its quantification. Complementary to ΔΔδ, the experimental determination of E allows a more reliable interpretation of the results and opens up new possibilities for the study of enantiodifferentiation data derived from novel NMR experiments, setup improvements or new CAs.

Review: Recent Advances in Small Molecule NMR: Improved HSQC and HSQMBC Experiments

annrep“Recent Advances in Small Molecule NMR: Improved HSQC and HSQMBC Experiments” by Laura Castañar and Teodor Parella. Annual Reports on NMR Spectroscopy, 2015, 84:163–232. DOI: 10.1016/bs.arnmr.2014.10.004

A general description of the latest developments in heteronuclear single-quantum correlation and heteronuclear single-quantum multiple bond correlation experiments designed for small molecules at the natural isotopic abundance is reported. Continue reading Review: Recent Advances in Small Molecule NMR: Improved HSQC and HSQMBC Experiments

In vivo MRS and ex vivo HRMAS in an Ischemic Rat Stroke Model

JCBMcover“In vivo and ex vivo Magnetic Resonance Spectroscopy of the Infarct and the Subventricular Zone in Experimental Stroke” by E. Jiménez-Xarrié, M. Davila, S. Gil-Perotín, A. Jurado-Rodríguez, A.P. Candiota, R. Delgado-Mederos, S. Lope-Piedrafita, J.M. García-Verdugo, C. Arús, J. Martí-Fàbregas. Journal of Cerebral Blood Flow & Metabolism, 2015, 35:828–834. DOI: 10.1038/jcbfm.2014.257

Ischemic stroke changes the metabolic pattern in the infarct area and also in other regions such as the ipsilateral subventricular zone (SVZi) where neural progenitor cells (NPCs) proliferation is enhanced in the mammalian and human brains. Magnetic resonance spectroscopy (MRS) provides metabolic information in vivo. With regard to NPCs proliferation, a resonance at 1.28 ppm has been described as an in vivo MRS biomarker of NPCs in the hippocampus of rats and humans. Continue reading In vivo MRS and ex vivo HRMAS in an Ischemic Rat Stroke Model

A New Polarizing Agent for Dissolution-DNP

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“A Benzyl Alcohol Derivative of BDPA Radical for Fast Dissolution Dynamic Nuclear Polarization NMR Spectroscopy” by José Luis Muñoz Gómez, Eva Monteagudo, Vega Lloveras, Teodor Parella, Jaume Veciana and José Vidal Gancedo. Organic & Biomolecular Chemistry, 2015, 13:2689-2693. DOI: 10.1039/C4OB02356K

 

The synthesis, structural characterization and the successful application of a carbon centered radical derived from 1,3-bisdiphenylene-2-phenylallyl (BDPA), its benzyl alcohol derivative (BA-BDPA), as a polarizing agent for Dynamic Nuclear Polarization (DNP) are described. Continue reading A New Polarizing Agent for Dissolution-DNP

Ultra high-resolution HSQC: Application to the efficient and accurate measurement of heteronuclear coupling constants

Journal cover: Chemical Communications“Ultra high-resolution HSQC: Application to the efficient and accurate measurement of heteronuclear coupling constants” by Núria Marcó,  Andre Fredi and Teodor Parella. Chemical Communications 2015, 51:3262-3265. DOI: 10.1039/C4CC10279G

A rapid NMR data acquisition strategy in terms of enhanced resolution per time unit for the simple and efficient determination of multiple coupling constants is described. The use of 13C spectral aliasing combined with broadband 1H homodecoupling allows accurate measurements from ultra high resolved 2D HSQC cross-peaks.imagen4

 

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Analysis of Sphingolipids Aggregates by NMR

SeRMN seminar

  • Date: Thursday 22th January, 2015
  • Hour: 12 am
  • Location:  SeRMN,  Facultats de Ciències i Biociències, C2/-135
  • Speaker:  André Fredi, SeRMN PhD Student

The sphingosine and sphingosine-1-phosphate are sphingolipids with important functions in different organisms. Continue reading Analysis of Sphingolipids Aggregates by NMR