Sodium ion binding in human serum.

T R Kissel; J R Sandifer; N Zumbulyadis

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PubMed · 7067085

Sodium ion binding in human serum.

T R Kissel·J R Sandifer·N Zumbulyadis

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Abstract

The amount of sodium ion binding in human sera and in dialyzed human sera was estimated from standard-addition titrations with an ion-selective electrode and from measurements of 23Na nuclear magnetic resonance (NMR) linewidth. For the untreated sera, maximum binding was 1% (1.4 mmol/L) as indicated by NMR; virtually no binding was found via the titration method. For dialyzed sera with low-sodium, normal-protein content, NMR indicated that sodium binding was less than 1.3% (0.14 mmol/L). The same dialyzed fluid analyzed with ion-selective electrodes shows no sodium binding, within the limits of experimental error (+/- 4%). Sodium ion binding to serum protein thus contributes only minimally to differences in sodium measurements observed between the direct (undiluted) ion-selective electrode and flame-photometric methods.

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Blood Proteins Chemistry, Clinical Humans Magnetic Resonance Spectroscopy Protein Binding Sodium Journal Article

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T R Kissel, J R Sandifer, N Zumbulyadis. 1982. Sodium ion binding in human serum.. https://pubmed.ncbi.nlm.nih.gov/7067085/

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