Occasionally measurement of the serumn or plasma concentration of sodium may give rise to falsely low results when carried out on a flame photometer or by an indirect reading ion selective electrode. The patients at risk are those with abnormally high serum concentrations of lipid or protein. These are, however, few: initially all low sodium concentrations as measured by flame photometry should...

Separated erythrocytes are washed repeatedly with iso-osmolar magnesium chloride solution, lysed by adding saponin, and sodium potassium measured in the diluted hemolysate by flame photometry. The coefficient of variation for the method was less than 4%. Reference intervals determined for a healthy population and hospitalized (elective surgery) patients without electrolyte disorders were 4.6-7....

Sera from patients with above-normal gamma-globulin concentrations give sodium values as much as 10% higher when measured in the Kodak Ektachem 400 analyzer than results obtained with the Beckman Astra-8 analyzer. Results obtained with the Astra were in agreement with flame photometry. A similar relative bias was observed for potassium measurement in the Ektachem. This discrepancy was corrected...

We describe a unique new approach to analytical spectroscopy, which makes use of a silicon-target vidicon tube to rapidly and repetitively scan ultraviolet and visible spectra. We discuss the concept and characteristics of the vidicon spectrometer and illustrate its application to simultaneousdeterminationof sodium and potassium In serum by flame photometry. Average values of coefficients of va...