Tag Archives: 13C-NMR

Simultaneous Enantiospecific Detection of Multiple Compounds in Mixtures using NMR Spectroscopy

2020-10-02Methods & Applications, Our Publications, Our Research13C-NMR, chiral recognition, chirality, enantiodifferentiation, enantiospecific, metabolic profiling, metabolites, metabolomics, metabonomics, mixture, nmr metholodogy, pure-shift NMR, simultaneousMiriam

Simultaneous Enantiospecific Detection of Multiple Compounds in Mixtures using NMR Spectroscopy, by Lars T. Kuhn, Kumar Motiram-Corral, Toby J. Athersuch, Teodor Parella, Míriam Pérez-Trujillo*

Angew. Chem. Int. Ed., 2020 / doi:10.1002/anie.202011727

Chirality plays a fundamental role in nature, but its detection and quantification still face many limitations. To date, the enantiospecific analysis of mixtures necessarily requires prior separation of the individual components. The simultaneous enantiospecific detection of multiple chiral molecules in a mixture represents a major challenge, which would lead to a significantly better understanding of the underlying biological processes; e.g. via enantiospecifically analysing metabolites in their native environment. Here, we report on the first in situ enantiospecific detection of a thirty‐nine‐component mixture. As a proof of concept, eighteen essential amino acids at physiological concentrations were simultaneously enantiospecifically detected using NMR spectroscopy and a chiral solvating agent. This work represents a first step towards the simultaneous multicomponent enantiospecific analysis of complex mixtures, a capability that will have substantial impact on metabolism studies, metabolic phenotyping, chemical reaction monitoring, and many other fields where complex mixtures containing chiral molecules require efficient characterisation.

^{Simultaneous enantiospecific detection of a mixture of amino acids by NMR spectroscopy}

This work has been selected to be presented as a talk at 2021 scientific conferences:

· 42nd FGMR (German Chemical Society, Magnetic Resonance Section) Annual Discussion Meeting – Virtual, Sep 27 to Oct 1.

· SMASH- Small Molecule NMR Conference 2021 – Virtual, Aug 30 to Sep 2.

· Euromar 2021 Conference – Virtual, 5 to 8 July.

· 10th GERMN (Spanish NMR group of the Real Sociedad Española de Química) biennial & 9th IberoAmerican NMR Meeting – Virtual, 26 to 19 April.

Prenatal cerebral and cardiac metabolic changes in a rabbit model of fetal growth restriction

2019-01-03Our Publications, Our Research13C-NMR, animal-model, hrmMiquel

Simões, Rui V., Miquel E. Cabañas, Carla Loreiro, Miriam Illa, Fatima Crispi & Eduard Gratacós. 2018. Assessment of prenatal cerebral and cardiac metabolic changes in a rabbit model of fetal growth restriction based on ¹³C-labelled substrate infusions and ex vivo multinuclear HRMAS. PLOS ONE 13(12). e0208784. DOI: 10.1371/journal.pone.0208784

Background: We have used a previously reported rabbit model of fetal growth restriction (FGR), reproducing perinatal neurodevelopmental and cardiovascular impairments, to investigate the main relative changes in cerebral and cardiac metabolism of term FGR fetuses during nutrient infusion.

Methods: FGR was induced in 9 pregnant New Zealand rabbits at 25 days of gestation: one horn used as FGR, by partial ligation of uteroplacental vessels, and the contralateral as control (appropriate for gestation age, AGA). At 30 days of gestation, fasted mothers under anesthesia were infused i.v. with 1-¹³C-glucose (4 mothers), 2-¹³C-acetate (3 mothers), or not infused (2 mothers). Fetal brain and heart samples were quickly harvested and frozen down. Brain cortex and heart apex regions from 30 fetuses were studied ex vivo by HRMAS at 4°C, acquiring multinuclear 1D and 2D spectra. The data were processed, quantified by peak deconvolution or integration, and normalized to sample weight.

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SeRMN contribution to Symmetry 2017 Conference

2017-10-26NMR Events & Courses, Our Research13C-NMR, chirality, enantiodifferentiation, hyperpolarization, nmr, sensitivity enhancementMiriam

Some of the SeRMN staff presented our last research work about chirality at The first International Conference on Symmetry, Symmetry 2017, that took place from16th to 18th October in Barcelona. Find below a summary of our contribution.

Míriam Pérez-Trujillo presented a lecture entitled: “Chiral Recognition by Dissolution Dynamic Nuclear Polarization NMR Spectroscopy”

Abstract: The recognition of enantiomeric molecules by chemical analytical techniques is still a challenge. A method based on d-DNP (dissolution dynamic nuclear polarization) NMR spectroscopy to study chiral recognition was described for the first time [1]. DNP allows boosting NMR sensitivity by several orders of magnitude, overcoming one of the main limitations of NMR spectroscopy [2]. A method integrating d-DNP and ¹³C NMR-aided enantiodifferentiation using chiral solvating agents (CSA) was developed, in which only the chiral analyte was hyperpolarized and selectively observed by NMR. The described method enhances the sensitivity of the conventional NMR-based procedure [3] and lightens the common problem of signal overlapping between analyte and CSA. As proof on concept, racemic metabolite ¹³C-labeled DL-methionine was enantiodifferentiated by a single-scan ¹³C NMR experiment. This method entails a step forward in the chiral recognition of small molecules by NMR spectroscopy; it opens new possibilities in situations where the sensitivity is limited, for example, when low analyte concentration available or when measurement of an insensitive nucleus required. The advantages and current limitations of the method, as well as future perspectives, are discussed.

Chiral Recognition by Dissolution DNP NMR Spectroscopy of 13C-Labeled DL-Methionine

2017-04-25Methods & Applications, Our Publications, Our Research13C-NMR, chiral recognition, chirality, d-DNP NMR, dissolution DNP, enantiodifferentiation, hyperpolarization, nmr, sensitivity enhancementEva

“Chiral Recognition by Dissolution DNP NMR Spectroscopy of ¹³C-Labeled DL-Methionine” By Eva Monteagudo^,Albert Virgili, Teodor Parella and Míriam Pérez-Trujillo^.. Anal. Chem., 2017, 89 (9), pp 4939–4944 DOI: 10.1021/acs.analchem.7b00156

A method based on d-DNP NMR spectroscopy to study chiral recognition is described for the first time. The enantiodifferentiation of a racemic metabolite in a millimolar aqueous solution using a chiral solvating agent was performed. Hyperpolarized ¹³C-labeled DL-methionine enantiomers were differently observed with a single-scan ¹³C NMR experiment, while the chiral auxiliary at thermal equilibrium remained unobserved. The method developed entails a step forward in the chiral recognition of small molecules by NMR spectroscopy, opening new possibilities in situations where the sensitivity is limited, for example, when a low concentration of analyte is available or when the measurement of an insensitive nucleus, like ¹³C, is required. The advantages and current limitations of the method, as well as future perspectives, are discussed.

Optimized polarization build-up times in dissolution DNP-NMR using a benzyl amino derivative of BDPA

2016-04-01Methods & Applications, Our Publications, Our Research13C-NMR, dissolution DNP, DNP, hyperpolarization, in-vitro-DNP, radicalsEva

“Optimized polarization build-up times in dissolution DNP-NMR using a benzyl amino derivative of BDPA” by José Luis. Muñoz Gómez, Eva Monteagudo, Vega LLoveras, Teodor Parella, Jaume Veciana and José Vidal Gancedo. RSC Advances, 2016, 6, 27077. DOI: 10.1039/c6ra00635c

The synthesis of two novel BDPA-like radicals, a benzyl amino (BAm-BDPA, 7) and a cyano (CN-BDPA, 5) derivative, is reported and their behaviour as polarizing agents for fast dissolution Dynamic Nuclear Polarization (DNP) is evaluated. Continue reading Optimized polarization build-up times in dissolution DNP-NMR using a benzyl amino derivative of BDPA →

A New Polarizing Agent for Dissolution-DNP

2015-01-26Our Publications13C-NMR, dissolution DNP, DNP, hyperpolarization, in-vitro-DNPEva

“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 →

Hyperpolarized 13C Magnetic Resonance in Acute Liver Failure Rats

2014-10-24Methods & Applications, Our Publications, Our Research13C-NMR, animal-model, biospec, DNP, hyperpolarization, in-vivo-DNP, metabolomics, MRI, MRSSilvia

“Real-time assessment of ¹³C metabolism reveals an early lactate increase in the brain of rats with acute liver failure” by Laia Chavarria, Jordi Romero-Giménez, Eva Monteagudo, Silvia Lope-Piedrafita, Juan Cordoba. NMR in Biomedicine (2014) 28:17-23. DOI: 10.1002/nbm.3226

Intracranial hypertension is a severe complication of acute liver failure (ALF) secondary to brain edema. The pathogenesis of cerebral edema in ALF is not clear, but seems to be related to energy metabolism in which lactate may have an important role. The aim of this study was to follow the synthesis of brain lactate using a novel in vivo metabolic technology in a rat model of ALF. Continue reading Hyperpolarized 13C Magnetic Resonance in Acute Liver Failure Rats →

Presentations at the Joint Annual Meeting ISMRM-ESMRMB 2014

2014-05-08News from the SeRMN, NMR Events & Courses, Our Research13C-NMR, animal-model, cancer, hyperpolarization, in-vivo-DNP, liver, MRSSilvia

Next week several SeRMN members will present our research work at the Joint Annual meeting ISMRM-ESMRMB 2014 that will take place in Milan (Italy) from 10^th to 16^th May. Find below a summary of our contributions.

Continue reading Presentations at the Joint Annual Meeting ISMRM-ESMRMB 2014 →

Enantiodifferentiation through 13C NMR Spectroscopy and CSAs

2013-11-19Methods & Applications, Our Publications, Our Research13C-NMR, chirality, enantiodifferentiation, metabolomicsMiriam

“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 →

Enantiodiscrimination Studies by ¹³C DNP-NMR Spectroscopy

2013-06-27Seminars13C-NMR, chirality, hyperpolarizationEva

SeRMN Seminar

Date: Thursday 27th June, 2013
Hour: 3 pm
Location: SeRMN, Facultats de Ciències i Biociències, C2/-135
Speaker: Eva Monteagudo, technician at SeRMN, UAB

Continue reading Enantiodiscrimination Studies by ¹³C DNP-NMR Spectroscopy →

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