Prevalence of Clinically Significant Differences in Sodium Measurements Due to Abnormal Protein Concentrations Using an Indirect Ion-Selective Electrode Method

2019 ◽  
Vol 4 (3) ◽  
pp. 427-432 ◽  
Author(s):  
Waddah Katrangi ◽  
Nikola A. Baumann ◽  
Ryan C. Nett ◽  
Brad S. Karon ◽  
Darci R. Block
1984 ◽  
Vol 56 (14) ◽  
pp. 2919-2920 ◽  
Author(s):  
Brent A. Fulton ◽  
Clifton E. Meloan ◽  
Michael D. Wichman ◽  
Robert C. Fry

Author(s):  
Heba Kashour ◽  
Lina Soubh

In this study, two analytical methods were used to determinate the protein, the ammonia ion selective electrode method and dye binding method using orange G and the spectrophotometer at λmax 478 nm by determining the linearity, accuracy, precision, limit of detection and limit of quantitation of each. In comparison, the dye binding method was chosen for its accuracy, repeatability, sensitivity (LOD, LOQ) and speed of performance. After that, it was applied to samples of prepared plain yogurt to study effect of different properties (source, heat treatment and type) of used milk on protein content of plain yogurt.


2018 ◽  
Vol 3 (3) ◽  
pp. 193
Author(s):  
Husain Sosidi ◽  
Buchari Buchari ◽  
Indra Noviandri

<p>The phenyl-3-methyl-4-benzoyl-5-pyrazolone (HPMBP) synthesized and characterized as ionophore in potentiometric analysis of ion selective electrode method (ISE) with polytetrafluoroethylene (PTFE) as the supporting phase. The pH and concentration of the ionic strength adjuster (ISA) were varied to know at the optimum pH and concentration of the ion-selective electrode (ESI) KNO<sub>3</sub>, thus potential Nd<sup>3+</sup> gives the best performance. Before use the PTFE membrane was immersed in a chloroform-HPMBP solution of 1.5-2.0% w/v for 24 h. The pH variation of the buffer solution was adjusted to the pH range of 2-10 using HCl and NaOH solutions, whereas the concentration of KNO<sub>3</sub> varies from 10<sup>-1</sup> to 10<sup>-3</sup> M. The concentration range of Nd<sup>3+</sup> is between 10<sup>-2</sup> and 10<sup>-7</sup> M. The electrode potential measurement results (E<sub>Nd</sub>) obtained the best performance value at pH 4 with KNO<sub>3</sub> concentration of 10<sup>-2</sup> M, sensitivity (S) 18.39 ± 1.2 mV/decade and response time less than 23 s.</p>


1975 ◽  
Vol 58 (3) ◽  
pp. 477-481 ◽  
Author(s):  
Laszlo Torma

Abstract A rapid and precise method for the determination of fluoride in feeds employs HC1 extraction of the sample. Acetate buffer and sodium citrate are added to control pH and ionic strength. The amount of fluoride is calculated from a standard curve after measuring the potentials of standard and sample solutions. Eight collaborators participated in the study of the method. Statistical values on 3 pairs of samples were calculated. The standard deviation, precision, coefficient of variation, and bias, respectively, were: Pair 1, 0.005071, 0.001763, 3.09, 0.0034; Pair 2, 0.037122, 0.006475, 1.82, 0.0258; Pair 3, 0.034587, 0.013021, 2.63, 0.0227. The results from the proposed method agreed favorably with the values obtained by using the official final action AOAC method, 7.089. The average and standard deviation, respectively, for individual samples by the proposed method were: Sample 3, 0.049, 0.0029; Sample 4, 0.059, 0.0021; Sample 5, 0.334, 0.0114; Sample 6, 0.341, 0.0101; Sample 7, 0.511, 0.0219; Sample 8, 0.492, 0.0237. By the official method the values were: Sample 3, 0.049, 0.0041; Sample 4, 0.058, 0.0029; Sample 5, 0.334, 0.0055; Sample 6, 0.331, 0.0082; Sample 7, 0.517, 0.0183; Sample 8, 0.499, 0.0175. The ion selective electrode method has been adopted as official first action.


1992 ◽  
Vol 38 (12) ◽  
pp. 2419-2422 ◽  
Author(s):  
J A Stone ◽  
J R Moriguchi ◽  
D R Notto ◽  
P E Murphy ◽  
C J Dass ◽  
...  

Abstract We have identified rare (approximately 0.2% of all samples), but clinically significant, discrepancies between serum or plasma sodium concentrations measured with the Kodak Ektachem 700's direct ion-selective electrode (ISE) method and concentrations measured with two other analyzers: the Beckman Synchron CX3's dilutional ISE instrument and the Radiometer KNA2 instrument for sodium-potassium analysis by the direct ISE method. The differences do not appear to be related to any previously identified sources of discrepancy, such as variations in triglycerides, bicarbonate, total protein, albumin, or gamma-globulin, the presence of paraproteins, or interference by benzalkonium chloride from heparinized catheters. They occurred despite the use of Gen 04 reference fluid on the Ektachem. We could not identify any drug or family of drugs that the patients had taken in common and that might influence the results. Until this problem is resolved, Ektachem users should be aware of the potential for discrepancies of &gt; 6 mmol/L in measurements of sodium concentrations.


Sign in / Sign up

Export Citation Format

Share Document