Category Archives: Methods & Applications

Posts describing the use of the nmr spectroscopy (MRS) methodology, either from a practical point of view (how to perform certain experiment), or from a more theoretical perspective (description of techniques and their application).

Easy measurement of one-bond proton-carbon and geminal proton-proton coupling constants in diastereotopic methylene groups

Straightforward measurement of individual 1J(CH) and 2J(HH) in diastereotopic CH2 groups” by Josep Saurí, Laura Castañar, Pau Nolis, Albert Virgili and Teodor ParellaJournal of Magnetic Resonance 242 (2014) 33–40DOI: 10.1016/j.jmr.2014.02.003

The C-HA cross-peak corresponding to a diastereotopic CHAHB methylene spin system exhibits a characteristic 1:0:1 multiplet pattern along the indirect dimension of a ω1-coupled HSQC spectrum. Continue reading Easy measurement of one-bond proton-carbon and geminal proton-proton coupling constants in diastereotopic methylene groups

CcpNmr Analysis – A useful tool for organic chemistry nmr?

SeRMN seminar

  • Date: Thursday 13th February, 2014
  • Hour: 10 am
  • Location: SeRMN, Facultats de Ciències i Biociències, C2/-135
  • Speaker: Miquel Cabañas, SeRMN

CcpNmr Analysis is a graphics-based interactive NMR spectrum visualisation, resonance assignment and data analysis program developed by The Collaborative Computing Project for NMR. as part of the CcpNmr suite of programs. Continue reading CcpNmr Analysis – A useful tool for organic chemistry nmr?

Stroke Therapy in Mice

PLoSONEcover“Factors Secreted by Endothelial Progenitor Cells Enhance Neurorepair Responses after Cerebral Ischemia in Mice” by Rosell, A., Morancho, A., Navarro-Sobrino, M., Martínez-Saez, E., Hernández-Guillamon, M., Lope-Piedrafita, S., Barceló, V., Borrás, F., Penalba, A., García-Bonilla, L., Montaner, J. PLoS ONE 8 (2013), e73244. DOI: 10.1371/journal.pone.0073244

Cell therapy with endothelial progenitor cells (EPCs) has emerged as a promising strategy to regenerate the brain after stroke. Continue reading Stroke Therapy in Mice

Pure Shift NMR & HOBS Experiments

SeRMN seminar

  • Date:  Monday 16th December, 2013
  • Hour: 10 am
  • Location:  SeRMN,  Facultats de Ciències i Biociències, C2/-135
  • Speaker:  Laura Castañar, SeRMN PhD Student & Teaching Assistant, Dept. of Chemistry.

Pure Shift NMR Spectroscopy (05-09-2013)

A NMR pulse scheme that provides full sensitivity in homodecouped band-selective NMR experiments is proposed. Continue reading Pure Shift NMR & HOBS Experiments

Implementing homo- and heterodecoupling in region-selective HSQMBC experiments

S10907807Implementing homo- and heterodecoupling in region-selective HSQMBC experiments” by Laura Castañar, Josep Sauri, Pau Nolis, Albert Virgili and Teodor ParellaJournal of Magnetic Resonance 238 (2014) 63-69.
DOI: 10.1016/j.jmr.2013.10.022
 

A NMR method to enhance the sensitivity and resolution in band-selective long-range heteronuclear correlation spectra is proposed. The excellent in-phase nature of the selHSQMBC experiment allows that homonuclear and/or heteronuclear decoupling can be achieved in the detected dimension of a 2D multiple-bond correlation map, obtaining simplified cross-peaks without their characteristic fine J multiplet structure. The experimental result is a resolution improvement while the highest sensitivity is also achieved. Specifically, it is shown that the 1H-homodecoupled band-selective (HOBS) HSQMBC experiment represents a new way to measure heteronuclear coupling constants from the simplified in-phase doublets generated along the detected dimension.

abstract

Pulse Programs Code for Bruker:

Data set Example:

References:

“Full sensitivity and enhanced resolution in homodecoupled band-selective NMR experiments” by L. Castañar, P. Nolis, A. Virgili and T. Parella. Chem. Eur. J. 2013, 19, 17283-17286. DOI: https://dx.doi.org/10.1002/chem.201303235

Enantiodifferentiation through 13C NMR Spectroscopy and CSAs

 13ac10887(85)13C NMR spectroscopy for the differentiation of enantiomers using chiral solvating agents” Míriam Pérez-Trujillo, Eva Monteagudo and Teodor Parella. Analytical Chemistry, 2013, 85 (22), pp 10887–10894. DOI: 10.1021/ac402580j

The utility of 13C NMR spectroscopy for the differentiation of enantiomers using chiral solvating agents (CSA) is stated. Three examples involving the enantiodifferentiation of a drug, a metabolite and a reactant in aqueous and organic solutions have been chosen to show it. Continue reading Enantiodifferentiation through 13C NMR Spectroscopy and CSAs

Full sensitivity and enhanced resolution in homodecoupled band-selective NMR experiments

cover“Full sensitivity and enhanced resolution in homodecoupled band-selective NMR experiments” by Laura Castañar, Pau Nolis, Albert Virgili and Teodor Parella. Chem. Eur. J. 2013, 19, 17283-17286.

DOI: 10.1002/chem.201303235

 

A NMR pulse scheme that provides full sensitivity in homodecouped band-selective NMR experiments is proposed. Continue reading Full sensitivity and enhanced resolution in homodecoupled band-selective NMR experiments

Simultaneous multi-slice excitation in Spatially encoded NMR experiments

cover“Simultaneous multi-slice excitation in Spatially encoded NMR experiments” by Laura Castañar, Pau Nolis, Albert Virgili and Teodor Parella. Chem. Eur. J. 2013, 19, 15472–1547. DOI: 10.1002/chem.201303272

multiple-sliceA novel strategy to enhance the experimental sensitivity in spatially encoded NMR experiments has been developed. Continue reading Simultaneous multi-slice excitation in Spatially encoded NMR experiments

Efficient and fast sign-sensitive determination of heteronuclear coupling constants

“Efficient and fast sign-sensitive determination of heteronuclear coupling constants” by Josep Saurí, Pau Nolis and Teodor ParellaJournal of Magnetic Resonance 236 (2013) 66–69. DOI: https://dx.doi.org/10.1016/j.jmr.2013.08.013

Two complementary 1D NMR approaches for the fast and easy determination of the magnitude and the sign of heteronuclear J(XH) coupling constants are proposed:The Up&Down technique relies on the direct analysis of anti-phase multiplets whereas the Left&Right technique is based on the relative displacement between separate IPAP components.

Continue reading Efficient and fast sign-sensitive determination of heteronuclear coupling constants

Free sugars quantification in intact plant tissue by HR-MAS NMR.

Planta - Journal cover“Assessment of a 1H high-resolution magic angle spinning NMR spectroscopy procedure for free sugars quantification in intact plant tissue” Teresa Delgado-Goñi, Sonia Campo, Juana Martín-Sitjar, Miquel E. Cabañas, Blanca San Segundo, Carles Arús; Planta, 238:397-413, 2013 (PDF file). DOI: 10.1007/s00425-013-1924-y

In most plants, sucrose is the primary product of photosynthesis, the transport form of assimilated carbon, and also one of the main factors determining sweetness in fresh fruits. Traditional methods for sugar quantification (mainly sucrose, glucose and fructose) require obtaining crude plant extracts, which sometimes involve substantial sample manipulation, making the process time-consuming and increasing the risk of sample degradation. Here, we describe and validate a fast method to determine sugar content in intact plant tissue by using high-resolution magic angle spinning nuclear magnetic resonance spectroscopy (HR-MAS NMR). Continue reading Free sugars quantification in intact plant tissue by HR-MAS NMR.