Direct potentiometric determination of sodium ion in blood. II. Influence of cations

Autor:	P. Bijster, K. L. J. Vink
Rok vydání:	1984
Předmět:	animal structures Magnesium Sodium Potassium Biochemistry (medical) Clinical Biochemistry Potentiometric titration Analytical chemistry chemistry.chemical_element Electrolyte EMF measurement Ion selective electrode Metal chemistry visual_art visual_art.visual_art_medium
Zdroj:	Clinical Chemistry. 30:865-870
ISSN:	1530-8561 0009-9147
Popis:	We measured the emf of NaCl solutions (120-160 mmol/L), with and without the addition of KCl (5-20 mmol/L), CaCl2 (2-8 mmol/L), or MgCl2 (1-4 mmol/L). Measurements were made with a home-built cell in steady-state and with two commercial direct potentiometric analyzers about 20 s after the sample was introduced. We calculated the sodium ion activity in the mixed NaCl-KCl solutions according to different thermodynamic theories and found almost the same results. We conclude that the influence on the emf of physiological concentrations of these cations was negligible when emf measurements were made in steady-state with the home-built cell. Of the three added cations, K+ caused the greatest increase in apparent sodium ion activity (up to about 4%) when emf measurements were made with commercial analyzers, owing to low salt-bridge concentration and the short measuring time of about 20 s.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::0d6a7bf8e7191075d53909eb2a72982d https://doi.org/10.1093/clinchem/30.6.865 Zobrazit plný text záznamu