Proton NMR spectroscopy of solvent-saturable resonances: a new approach to study pH effects in situ.

Abstract:

:It is shown that the effect of pH changes can be measured in proton NMR spectra through the pH sensitivity of the signal intensities of metabolite protons exchanging with water. To observe this phenomenon, pulse sequences must be used that can sensitively observe these exchangeable protons under physiological conditions, which is achieved by avoiding magnetization transfer signal losses due to water saturation for solvent suppression purposes. These methods provide an order-of-magnitude enhancement of many signals between 5 and 10 ppm, containing both N-bound protons as well as aromatic C-H protons coupled to them, the intensity of which is influenced by exchange-relayed saturation. As a first application, the effects of pH change on these resonances are studied ex vivo (perfused cells) and in vivo (cat brain).

journal_name

Magn Reson Med

authors

Mori S,Eleff SM,Pilatus U,Mori N,van Zijl PC

doi

10.1002/mrm.1910400105

subject

Has Abstract

pub_date

1998-07-01 00:00:00

pages

36-42

issue

1

eissn

0740-3194

issn

1522-2594

journal_volume

40

pub_type

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