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 Medjournal_title
Magnetic resonance in medicineauthors
Mori S,Eleff SM,Pilatus U,Mori N,van Zijl PCdoi
10.1002/mrm.1910400105subject
Has Abstractpub_date
1998-07-01 00:00:00pages
36-42issue
1eissn
0740-3194issn
1522-2594journal_volume
40pub_type
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