Magnetic resonance imaging (MRI) relies on the topological distribution of the intense water NMR signal and may be used to report about changes in the internal structures of fruits associated to ripening, storing, pathogen infection. Herein the use of CEST-MRI (chemical exchange saturation transfer) is introduced to show that in addition to structural information, insights into the presence in the fruits of specific chemicals may be gained. Asparagine is present in plums at relatively high concentration (≈10-20 mM) and owns two amide protons (at 2.1 and 2.8 ppm down field from water) in slow exchange with water protons. By irradiating the amide resonances with a proper rf-field it is possible to transfer saturated magnetization to the "bulk" water signal. The attained change in signal intensity reflects the extent of prototropic exchange between amide and water protons that is modulated by the local pH.

Asparagine in plums detected by CEST–MRI

DELLI CASTELLI, Daniela;GULLINO, Maria Lodovica;AIME, Silvio
2015-01-01

Abstract

Magnetic resonance imaging (MRI) relies on the topological distribution of the intense water NMR signal and may be used to report about changes in the internal structures of fruits associated to ripening, storing, pathogen infection. Herein the use of CEST-MRI (chemical exchange saturation transfer) is introduced to show that in addition to structural information, insights into the presence in the fruits of specific chemicals may be gained. Asparagine is present in plums at relatively high concentration (≈10-20 mM) and owns two amide protons (at 2.1 and 2.8 ppm down field from water) in slow exchange with water protons. By irradiating the amide resonances with a proper rf-field it is possible to transfer saturated magnetization to the "bulk" water signal. The attained change in signal intensity reflects the extent of prototropic exchange between amide and water protons that is modulated by the local pH.
2015
169
1
4
Rachele Podda;Daniela Delli Castelli;Giuseppe Digilio;Maria Lodovica Gullino;Silvio Aime
File in questo prodotto:
File Dimensione Formato  
postprint.pdf

Accesso aperto

Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 951.27 kB
Formato Adobe PDF
951.27 kB Adobe PDF Visualizza/Apri
pdf editoriale.pdf

Accesso riservato

Tipo di file: PDF EDITORIALE
Dimensione 746.76 kB
Formato Adobe PDF
746.76 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/152982
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 8
  • ???jsp.display-item.citation.isi??? 6
social impact