ChemInform Abstract: ON-STREAM DETERMINATION OF AMMONIA IN BOILER FEED-WATER WITH AN AMMONIUM ION SELECTIVE ELECTRODE AND AN AMMONIUM PROBE

New methods for the determination of L-asparagine and arginine are described. Solutions containing L-asparagine were pumped through an asparaginase tube, which catalyzed the hydrolysis of L-asparagine to L-aspartic acid and ammonium ion. For L-arginine determination, solutions containing L-arginine were pumped through an arginase–urease tube. This dual enzyme tube catalyzed the conversion of L-arginine to L-ornithine, carbon dioxide, and ammonium ion. The ammonium ion concentrations in the effluent of the enzyme tubes were determined quantitatively by an ammonium-ion-selective electrode. The potentiometric response of the electrode was directly proportional to the logarithm of the concentration of L-asparagine and L-arginine in the range of 0.1–50 mM. An equation relating the electrode response and the substrate concentration is derived.

Download Full-text

Enzymatic determination of urea in undiluted whole blood by flow injection analysis using an ammonium ion-selective electrode

Analytica Chimica Acta ◽

10.1016/s0003-2670(00)84567-5 ◽

1988 ◽

Vol 209 ◽

pp. 239-248 ◽

Cited By ~ 29

Author(s):

Bo A. Petersson

Keyword(s):

Flow Injection ◽

Flow Injection Analysis ◽

Whole Blood ◽

Ion Selective Electrode ◽

Ammonium Ion ◽

Selective Electrode ◽

Enzymatic Determination

Download Full-text

Titration of sulphates and lead using lead ion selective electrode

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19810368 ◽

1981 ◽

Vol 46 (2) ◽

pp. 368-376 ◽

Cited By ~ 4

Author(s):

Josef Veselý

Keyword(s):

Ionic Strength ◽

Electrode Surface ◽

Salt Content ◽

Ion Selective Electrode ◽

Lead Ion ◽

Selective Electrode ◽

Limit Of Determination ◽

Total Salt Content ◽

Automatic Titration

Titration of sulphates with lead perchlorate employing lead ion selective electrode indication was studied using additions of various organic solvents at different pH' and ionic strength values. As the optimum emerged systems with 60-70% 1,4-dioxane, pH' 5.3-5.6. After dehydration with sodium hydroxide, dioxane must be freed from the electrode surface-oxidizing impurities by their reduction with sodium metal and subsequent distillation. The method was applied to determination of sulphates in mountain spring waters. Units of ppm can be determined; the limit of determination, however, depends considerably on the content of dioxane, total salt content in the sample, and speed of the semi-automatic titration. Lead can be determined with EDTA in concentrations down to c(Pb2+) = 5 . 10-6 mol l-1.

Download Full-text

Using MoS2/Fe3O4 as Ion-Electron Transduction Layer to Manufacture All-Solid-State Ion-Selective Electrode for Determination of Serum Potassium

Chemosensors ◽

10.3390/chemosensors9070155 ◽

2021 ◽

Vol 9 (7) ◽

pp. 155

Author(s):

Yan Su ◽

Ting Liu ◽

Caiqiao Song ◽

Aiqiao Fan ◽

Nan Zhu ◽

...

Keyword(s):

High Performance ◽

Accurate Determination ◽

Water Layer ◽

Ion Selective Electrode ◽

Potential Response ◽

Selective Electrode ◽

Response Measurement ◽

Long Term Stability

As an essential electrolyte for the human body, the potassium ion (K+) plays many physiological roles in living cells, so the rapid and accurate determination of serum K+ is of great significance. In this work, we developed a solid-contact ion-selective electrode (SC-ISE) using MoS2/Fe3O4 composites as the ion-to-electron transducer to determine serum K+. The potential response measurement of MoS2/Fe3O4/K+-ISE shows a Nernst response by a slope of 55.2 ± 0.1 mV/decade and a low detection limit of 6.3 × 10−6 M. The proposed electrode exhibits outstanding resistance to the interference of O2, CO2, light, and water layer formation. Remarkably, it also presents a high performance in potential reproducibility and long-term stability.

Download Full-text