The effect of the supporting electrolyte on the voltammetric determination of the veterinary drug nitroxinil

AbstractIn this study the application of home-made unmodified (GC) and bulk modified boron doped glassy carbon (GCB) electrodes for the voltammetric determination of the linuron was investigated. The electrodes were synthesized with a moderate temperature treatment (1000°C). Obtained results were compared with the electrochemical determination of the linuron using a commercial glassy carbon electrode (GC-Metrohm). The peak potential (E p ) of linuron oxidation in 0.1 mol dm−3 H2SO4 as electrolyte was similar for all applied electrodes: 1.31, 1.34 and 1.28 V for GCB, GC and GC-Metrohm electrodes, respectively. Potential of linuron oxidation and current density depend on the pH of supporting electrolyte. Applying GCB and GC-Metrohm electrodes the most intensive electrochemical response for linuron was obtained in strongly acidic solution (0.1 mol dm−3 H2SO4). Applying the boron doped glassy carbon electrode the broadest linear range (0.005–0.1 µmol cm−3) for the linuron determination was obtained. The results of voltammetric determination of the linuron in spiked water samples showed good correlation between added and found amounts of linuron and also are in good agreement with the results obtained by HPLC-UV method. This appears to be the first application of a boron doped glassy carbon electrode for voltammetric determination of the environmental important compounds.

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Voltammetric Determination of Isopropylmethylphenols in Herbal Spices

Molecules ◽

10.3390/molecules26206095 ◽

2021 ◽

Vol 26 (20) ◽

pp. 6095

Author(s):

Magdalena Jakubczyk ◽

Slawomir Michalkiewicz ◽

Agata Skorupa ◽

Daria Slefarska

Keyword(s):

Electrode Materials ◽

Supporting Electrolyte ◽

Sodium Perchlorate ◽

Total Content ◽

Standard Addition ◽

Differential Pulse ◽

Voltammetric Determination ◽

Pulse Voltammetry ◽

Good Agreement

Thymol and carvacrol—the components of herbal spices—are known for their broad biological activity as antimicrobials and antioxidants. For this reason, it is important to develop new methods for their determination in plant material. A simple, rapid, and sensitive method for determination of total content of these analytes in herbal spices using differential pulse voltammetry (DPV) has been developed. The basis of the research is the oxidation process of isopropylmethylphenols on a platinum microelectrode in glacial acetic acid containing acetonitrile (20%, v/v) and 0.1 mol L−1 sodium perchlorate as the supporting electrolyte. Linear voltammetric responses for thymol and carvacrol were obtained in a wide concentration range from 0.39–1105 and 0.47–640 µg mL−1, with a low detection limit of 0.04 and 0.05 µg mL−1, respectively. The analysis was performed using the multiple standard addition method. The results of the voltammetric determination are in good agreement with the data of the standard chromatographic method. To the best of our knowledge, this is the first presentation of an electrochemical procedure to determine these compounds in these environmental and electrode materials.

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Square-wave voltammetric determination of drospirenone and ethinylestradiol in pharmaceutical dosage form using square wave technique

European Journal of Chemistry ◽

10.5155/eurjchem.10.4.305-316.1901 ◽

2019 ◽

Vol 10 (4) ◽

pp. 305-316

Author(s):

Ibrahim Hassan Habib ◽

Mohammed Salem Rizk ◽

Maha Sultan ◽

Dalia Mohamed ◽

Rehab Moussa Tony

Keyword(s):

Supporting Electrolyte ◽

Reference Method ◽

Pulse Amplitude ◽

Voltammetric Determination ◽

Pharmaceutical Dosage Form ◽

Square Wave ◽

Significant Difference ◽

Scan Rate ◽

Wave Technique

Cathodic voltammetric behaviors of drospirenone and ethinylestradiol were used for the simultaneous determination of both drugs in bulk and in pharmaceutical formulation (Yasmin® tablets) without the interference of excipients. The determinations were made on hanging mercury dropping electrode using square-wave technique in a voltammetric cell containing 10 mL of 0.04 mole/L Britton-Robinson. After every aliquot addition, the solution was stirred for 10 s at 1000 rpm, rested for 10 s then square wave voltammetry mode was ramped from +100 to -1700 mV with scan rate of 100 mV/s, pulse amplitude of 50 mV and measurement time of 5 ms. Several factors such as pH, type of supporting electrolyte, pulse amplitude and scan rate were studied to optimize the condition for voltammetric determination of these drugs. With optimized experimental parameters, a good linearity was obtained for both drugs over a range of 1.36×10-6 to 1.91×10-7 mole/L and 6.75×10-8 to 6.07×10-7 mol/L of drospirenone and ethinylestradiol, respectively. Characterization of the proposed method was done according to International Conference on Harmonization, Q2B: Validation of Analytical procedures. The proposed method was statistically compared with the reference method and the results revealed no significant difference regarding accuracy and precision.

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Voltammetric determination of the trace amounts of bromate in drinking water after pre-concentration on hydrous γ-Al2O3

Open Chemistry ◽

10.2478/bf02476203 ◽

2004 ◽

Vol 2 (3) ◽

pp. 491-499 ◽

Cited By ~ 2

Author(s):

Honorata Kościelna ◽

Maria Ren

Keyword(s):

Drinking Water ◽

Cation Exchange ◽

Exchange Resin ◽

Supporting Electrolyte ◽

Cation Exchange Resin ◽

Differential Pulse ◽

Voltammetric Determination ◽

Reduction Peak ◽

Pre Treatment

AbstractA differential pulse voltammetric (DPV) method for the determination of bromate in drinking water, after pre-concentration on γ-Al2O3, is proposed. The reduction peak of bromate has been observed at the potential Ep-−1.6 V in an ammonia buffer as a supporting electrolyte. The method has been successfully applied to determine a bromate concentration of 2.5 μg·l−1 in drinking water (RSD=6.1%, n=7). A sample pre-treatment with a column filled with mixed cation-exchange resin in Ag, Ba and H forms was needed before pre-concentration of bromate on alumina.

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Voltammetric Determination of Pd(II) Using 5-Hydroxyimino-4-imino-1,3-thiazolidin-2-one after a Thermal Activation of the Interaction

Chemistry & Chemical Technology ◽

10.23939/chcht15.03.324 ◽

2021 ◽

Vol 15 (3) ◽

pp. 324-329

Author(s):

Petro Rydchuk ◽

◽

Oksana Labyk ◽

Lesya Oleksiv ◽

Oleksandr Tymoshuk ◽

...

Keyword(s):

Thermal Activation ◽

Limit Of Detection ◽

Supporting Electrolyte ◽

Voltammetric Determination ◽

Real Sample ◽

Optimal Conditions ◽

Voltammetric Method ◽

The Real ◽

Ph Range

The interaction of Pd(II) with 5-hydroxyimino-4-imino-1,3-thiazolidin-2-one (HITO) was investigated over the pH range of 1.0–10.0. Optimal conditions for the voltammetric determination of Pd(II) were established. A new voltammetric method of Pd(II) determination by the peak of complex using NaCl as a supporting electrolyte at pH 2.0 was developed with the limit of detection 2.0∙10-7 M. The study of the method’s selectivity was presented in the work. The correctness of the method was confirmed by the analysis of model solutions and the real sample (resistor SP5-35B).

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