% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@ARTICLE{Schepkin:120657,
      author       = {V. D. Schepkin and A. Neubauer and A. Nagel$^*$ and T. F.
                      Budinger},
      title        = {{C}omparison of potassium and sodium binding in vivo and in
                      agarose samples using {TQTPPI} pulse sequence.},
      journal      = {Journal of magnetic resonance},
      volume       = {277},
      issn         = {1090-7807},
      address      = {Amsterdam [u.a.]},
      publisher    = {Elsevier},
      reportid     = {DKFZ-2017-01084},
      pages        = {162 - 168},
      year         = {2017},
      abstract     = {Potassium and sodium specific binding in vivo were explored
                      at 21.1T by triple quantum (TQ) magnetic resonance (MR)
                      signals without filtration to achieve high sensitivities and
                      precise quantifications. The pulse sequence used time
                      proportional phase increments (TPPI). During simultaneous
                      phase-time increments, it provided total single quantum (SQ)
                      and TQ MR signals in the second dimension at single and
                      triple quantum frequencies, respectively. The detection of
                      both TQ and SQ signals was performed at identical
                      experimental conditions and the resulting TQ signal equals
                      $60±3\%$ of the SQ signal when all ions experience
                      sufficient time for binding. In a rat head in vivo the TQ
                      percentage relative to SQ for potassium is $41.5±3\%$ and
                      for sodium is $16.1±1\%.$ These percentages were compared
                      to the matching values in an agarose tissue model with MR
                      relaxation times similar to those of mammalian brain tissue.
                      The sodium TQ signal in agarose samples decreased in the
                      presence of potassium, suggesting a competitive binding of
                      potassium relative to sodium ions for the same binding
                      sites. The TQTPPI signals correspond to almost two times
                      more effective binding of potassium than sodium. In vivo, up
                      to $∼69\%$ of total potassium and $∼27\%$ of total
                      sodium can be regarded as bound or experiencing an
                      association time in the range of several milliseconds.
                      Experimental data analyses show that more than half of the
                      in vivo total sodium TQ signal could be from extracellular
                      space, which is an important factor for quantification of
                      intracellular MR signals.},
      cin          = {E020},
      ddc          = {550},
      cid          = {I:(DE-He78)E020-20160331},
      pnm          = {315 - Imaging and radiooncology (POF3-315)},
      pid          = {G:(DE-HGF)POF3-315},
      typ          = {PUB:(DE-HGF)16},
      pubmed       = {pmid:28314206},
      doi          = {10.1016/j.jmr.2017.03.003},
      url          = {https://inrepo02.dkfz.de/record/120657},
}