The intracellular sodium concentration and intracellular volume of human red blood cells were determined from 23Na and 1H NMR spectra. It is shown that sodium dissolved in the intracellular water has a concentration higher than that previously published. The intracellular sodium concentration measur
Measurement of the intracellular concentration of oxygen in a cell perfusion system
โ Scribed by Kai Chen; Cheng E. Ng; Jay L. Zweier; Periannan Kuppusamy; Jerry D. Glickson; Harold M. Swartz
- Publisher
- John Wiley and Sons
- Year
- 1994
- Tongue
- English
- Weight
- 479 KB
- Volume
- 31
- Category
- Article
- ISSN
- 0740-3194
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โฆ Synopsis
Abstract
[O~2~] was measured in the embedding material (alginate) in a typical apparatus for conducting studies of viable cells with NMR, using low frequency EPR. In suspension cultures respiration was independent of [O~2~] in the perfusing media down to about 1 ฮผM while in alginate beads, the comparable value was 70 ฮผM, indicating that the alginate was a very substantial barrier to the free diffusion of oxygen. With knowledge of [O~2~] in the various compartments, [O~2~] in the perfusing medium can be increased and the full power of NMR can be used to provide information on metabolism under various conditions. These results also provide evidence supporting the feasibility and usefulness of EPR techniques using nitroxides to measure [O~2~] in macroscopic samples such as NMR perfusion tubes. This technique is rapid, apparently nonperturbing, and enables one to differentiate between the concentrations of oxygen in different compartments.
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