• Aucun résultat trouvé

Accurate determination of pH via hyperpolarized $^{129}$Xe NMR

N/A
N/A
Protected

Academic year: 2021

Partager "Accurate determination of pH via hyperpolarized $^{129}$Xe NMR"

Copied!
3
0
0

Texte intégral

(1)

HAL Id: cea-02341010

https://hal-cea.archives-ouvertes.fr/cea-02341010

Submitted on 31 Oct 2019

HAL is a multi-disciplinary open access

archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.

L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Accurate determination of pH via hyperpolarized

129

Xe

NMR

Estelle Léonce, Thierry Brotin, Jean-Pierre Dognon, Patrick Berthault

To cite this version:

Estelle Léonce, Thierry Brotin, Jean-Pierre Dognon, Patrick Berthault. Accurate determination of pH via hyperpolarized 129Xe NMR. 39th FGMR Annual Discussion Meeting, Sep 2017, Bayreuth, Germany. �cea-02341010�

(2)

Accurate determination of pH via hyperpolarized 129Xe NMR

Estelle Léonce!, Thierry Brotin2

, jean-Pierre Dognon', Patrick Berthault'

7NIMBE, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 97797 Gif-sur-Yvette, France

2 ENS Lyon, Laboratoire de Chimie, 69364 Lyon cedex 07, France

Contact: patrick.berthault@cea.fr

Measuring non-invasively and in a local way the in vivo extra-cellular pH is of importance for the diagnosis of insidious pathologies such as various cancers. For one decade, the use of hyperpolarized agents has been proposed; each method possesses its own advantage and inconvenience, and their applicability in the in vivo domain is not always straightforward. For instance,~ome ..., years ago, we proposed the use of cage-molecules bearing ionizable groups, in which laser-polarized xenon exhibits a pH-dependent chemical shift.' However extracting pH from measurement of the absolute chemical shift of caged xenon or even of the chemical shift difference between free and caged xenon is susceptible to be biased by external parameters such as temperature and magnetic susceptibility fluctuation.

Here we present an approach which is simple and fast to implement and which should be exempt of most of the problems encountered in vivo. The idea is to perform a differential measurement by using a pair of pH-sensitive 129Xe NMR-based sensors. The method is rendered very pH-sensitive via the choice of two xenon host molecules in

129XeNMR

~

RO a 0 OR OR

,

0

. / ' \ (CHili (C~l2 (C~J?

1

OR' R'O "0 0/ OR'

~

1 : R = CH2COOH; R' = CH2COOH 2: R = CH2COOH; R'= H Xe@2 76 74 Xe@l T 72 70 ppm

which the frequency of the noble gas signal varies in opposite manner with the H+ concentration. For this proof-of-concept, the two cryptophanes

described in Figure 1 have been used. The measurement shown to independent temperature ionic strength. is be of and

Figure 1. High field region of the 129Xe NMR spectrum of an aqueous solution containing the two cryptophanes 1 and 2 at 1 !-lM each. Evolution as a function of temperature.

(1) Berthault, P.; Desvaux, H.; Wendlinger, T.; Gyejacquot, M.; Stopin, A.; Brotin, T.; Dutasta,

(3)

Abstract submission form for the

39th FGMR Annual Discussion Meeting 2017 Joint Discussion Meeting of the French and German

Magnetic Resonance Societies

Please use this form and the template on next page to write your abstracto

To submit your abstract, save this file as a doc or docx file, na me it as follows:

Surname_FirstName.docx (with the surname and first na me of the presenting

author), and email it to:

'"

fgmr-gmrm-2017@uni-bayreuth.de

Please choose the desired presentation type:

IZI

Oral

IZI

Poster

Please choose the session for presenting your work:

D

EPR methods (chair: Dieter Suter)

D

Small molecules / Homogeneous catalysis (chair: Ruth Gschwind)

r

-D

Soft matter (chair: Kay Saalwachter)

D

Relaxometry (chair: Ernst

Rô~ler)

D

Computational methods / Fast NMR (chair: Steffen Glaser)

D

NMR crystallography / Materials (chair: Charlotte Martineau-Corcos)

D

Structural biology (chair: Bruno Kieffer)

D

Bio-macromolecules and dynamics (chair: Paul Rôsch)

D

MRI (chair: Olivier Girard)

D

New methods (chair: Anne Lesage)

IZI

Hyperpolarization methods (chair: Patrick Berthault)

Figure

Figure 1.  High field region of the 1 2 9Xe  NMR  spectrum of an aqueous solution containing the two  cryptophanes  1  and  2  at  1  !-lM each

Références

Documents relatifs

We treated TGFα-EGFR WT ;InkΔ2/3 −/− ;PTEN lox tumor cell cultures with gefitinib for 16 hours and harvested total RNA at different times and performed qRT-PCR to measure the

SAS+S refers to the method proposed in the present work and intermediate refers to the calculation where only multiple ligand-to-metal charge trans- fer configurations were removed

Elle permet aussi d’observer chez les patients suspects de gonococcie, la présence de polynucléaire contenant des diplocoques à Gram négatif ; ces bactéries sont

Here again, this operation is not really necessary for position measurements: the relevant information is con- tained in the slope at the origin of the unbiased imaginary part of

Alice encodes information in both polarization imodes using a single silicon photonics transmitter.. Bob, on the other hand, uses another copy of the silicon

Figure 4 shows the corresponding indicated power production efficiency, CO emissions and coefficient of variation (COV) in indicated mean effective pressure (imep). The CO

surface supérieure à celle qui serait nécessaire pour produire 92 tonnes de céréales. Dès lors, en dehors de ces critères restrictifs le « privilège de l’agriculteur » n’en est

Fracture of Zircaloy-4 cladding tubes with or without hydride blisters in uniaxial to plane strain conditions with standard and optimized expansion due to compression tests...