Determination of stability constant of copper(II) with thiosemicarbazide by use of a cupric ion-selective electrode

Abstract A method for determining biuret in urea and mixed fertilizers by using a cupric ion selective electrode (CISE) has been developed to take advantage of the simplicity of the apparatus. The method is based on the same principle as the atomic absorption spectrophotometric (AAS) method, 2.091-2.093: formation of a biuret-copper complex, elimination of excess copper, and determination of complexed copper. However, some changes were needed to eliminate starch and alcohol interferences. The method was tested for ruggedness and then compared with the AAS method for 4 fertilizer samples. Averages and variances were equivalent at the 99% confidence level according to t- and F-tests. A collaborative study is recommended to compare behavior of both methods in different laboratories.

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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.

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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.

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