All posts by Miriam

Simultaneous 1H and 13C NMR enantiodifferentiation from highly-resolved pure shift HSQC spectra

CoverIssue“Simultaneous 1H and 13C NMR enantiodifferentiation from highly-resolved pure shift HSQC spectra” by Miriam Pérez-Trujillo, Laura Castañar, Eva Monteagudo, Lars T. Kuhn, Pau Nolis, Albert Virgili, R. Thomas Williamson and Teodor Parella. Chemical Communications  50:10214-10217 (2014). DOI: 10.1039/C4CC04077E

NMR-aided discrimination of enantiomers using chiral solvating agents (CSAs) is a well established method of enantiodifferentiation and measurement of enantiomeric ratios (er). The analysis is traditionally performed by observing chemical shift differences (ΔΔδ) in 1H signals by conventional 1D 1H NMR spectra. However, low ΔΔδ values and signal overlap caused by complex multiplets lead to the lack of spectral signal dispersion that preclude a straightforward analysis. Continue reading Simultaneous 1H and 13C NMR enantiodifferentiation from highly-resolved pure shift HSQC spectra

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

Presentations at the SMASH NMR Conference 2013

Next week several SeRMN members will present our research work at the SMASH NMR Conference 2013 that will take place in Santiago de Compostela (Spain) from 22nd to 25th September. Find below a summary of our contributions.SMASH-2 Continue reading Presentations at the SMASH NMR Conference 2013

NMR-based Protocol for Ecometabolomics

13MEE“Ecometabolomics: Optimized NMR-based method” by Albert Rivas-Ubach, Miriam Pérez-Trujillo, Jordi Sardans, Albert Gargallo-Garriga, Teodor Parella, Josep Peñuelas. Methods in Ecology and Evolution, February 2013. DOI: 10.1111/2041-210X.12028

Metabolomics is allowing great advances in biological sciences and in particular Ecometabolomics (metabolomic approach for ecological studies). Ecometabolomics is a powerful tool that allows identifying changes in the metabolome of individuals of the same species associated to environmental changes, detecting and identifying biological markers. Continue reading NMR-based Protocol for Ecometabolomics

Tuberculosis mycobacterium and microscopic cords formation. Related to their virulence

“Cyclopropanation of α-mycolic acids is not required for cording in non-tuberculous mycobacteria” Cecilia Brambilla, Alejandro Sánchez-Chardi, Míriam Pérez-Trujillo, Esther Julián, Marina Luquin.  Microbiology, March 2012. DOI: 10.1099/mic.0.057919-0

Mycobacterium tuberculosis and Mycobacterium bovis are the principal agents responsible for human tuberculosis and tuberculosis in domestic and wild animals. Both form microscopic cords, a phenotypic characteristic that has been related to their virulence. The compounds responsible for cording are unknown, but a recent work has shown that cording could be related to the fine structure of α-mycolic acids. Continue reading Tuberculosis mycobacterium and microscopic cords formation. Related to their virulence

Metabolic profiling for the detection of early effects of environmental and lifestyle exposure to cadmium.

“Metabolic Profiling Detects Early Effects of Environmental and Lifestyle Exposure to Cadmium in a Human Population” JK Ellis, TJ Athersuch, LDK Thomas, F Teichert, M Pérez-Trujillo, C Svendsen, D J. Spurgeon, R Singh, L Järup, JG Bundy and HC Keun.  BMC Medicine, February 2012.  DOI: 10.1186/1741-7015-10-61

The ‘exposome’ represents the accumulation of all environmental exposures across a lifetime. Top-down strategies are required to assess something this comprehensive, and could transform our understanding of how environmental factors affect human health. Metabolic profiling (metabonomics / metabolomics)  defines an individual’s metabolic phenotype, which is influenced by genotype, diet, lifestyle, health and xenobiotic exposure, and could also reveal intermediate biomarkers for disease risk that reflect adaptive response to exposure. Continue reading Metabolic profiling for the detection of early effects of environmental and lifestyle exposure to cadmium.

Presentations to the Ibero-American NMR & GERMN Bienal & Iberian NMR joint meeting

Next week several SeRMN members will present our research work at the IV Ibero-American NMR – VI GERMN Bienal – III Iberian NMR joint meeting that will take place in Aveiro (Portugal) from 25th to 28th September. Find below a summary of our contributions.

Continue reading Presentations to the Ibero-American NMR & GERMN Bienal & Iberian NMR joint meeting

ECOMETABOLOMICS: Metabolomics in Ecological Studies

“Strong relationship between elemental stoichiometry and metabolome in plants” Albert Rivas-Ubach, Jordi Sardans, Miriam Pérez-Trujillo, Marc Estiarte and Josep Peñuelas.  PNAS, February 2012. DOI: 10.1073/pnas.1116092109

Shifts in the elemental stoichiometry of organisms in response to their ontogeny and to changing environmental conditions should be related to metabolomic changes because elements operate mostly as parts of molecular compounds. Here we show this relationship in leaves of Erica multiflora throughout their seasonal development and in response to moderate experimental field conditions of drought and warming. Continue reading ECOMETABOLOMICS: Metabolomics in Ecological Studies

HPLC-DAD-(SPE)-NMR/MS II: fundamentals and working modes

This hyphenated technique combines HPLC with three complementary detection techniques – NMR Spectroscopy, Mass Spectrometry and Diode Array Detection. It is a highly rich information source, which can be obtained by one-shot analysis.

There are three different modes of work: Flow-NMR, Stop-Flow and SPE-storage; and depending on the scientific problem one or another will be the most adequate. Continue reading HPLC-DAD-(SPE)-NMR/MS II: fundamentals and working modes