Electrochemical Study and Direct Determination of Adenosine-5′-Monophosphate Coupled to 6-Thioguanosine and a Glassy Carbon Modified Electrode with Gold Nanoparticles

Background: The total antioxidant capacity of yam food grown in southern African regions was investigated by a polyglycine-glassy carbon modified electrode. The modified electrode was fabricated using glycine solution on glassy carbon electrode by electrodeposition method. The proposed modified electrode is found to be nearly 3.15-fold more sensitive than the bare electrode. For the measurement of the total antioxidants of yam, differential pulse stripping voltammetry (DPSV) was employed with standard quercetin compound. Methods: The total antioxidant capacity of yam was deduced by DPSV and cyclic voltammetry (CV) methods. The basic parameters for the stripping technique such as pH, accumulation time and accumulation potential were optimized as 20 s, 200 mV and a pH of 3 Britton-Robinson (B-R) buffer solutions in 0.5 mg quercetin/L, respectively. Results: In the optimization condition, the linear working range was determined between 5.0 μg/L and 80.0 µg/L for the quercetin. The detection (LOD) and quantification (LOQ) limits of quercetin were found to be 0.39 µg/L and 1.39 µg/L on the modified electrode by DPSV, respectively. The procedure was also applied to natural yam samples and total antioxidant capacity of 0.1 kg of yam was determined as 96.15 ± 0.85 µg/L of equivalent quercetin at 95% confidence level with the relative standard deviations of 0.88%. Conclusion: Sensitive and selective voltammetric method was developed for the determination of total antioxidant capacity in yam. Moreover, the modified polyglycine-glassy carbon electrode was constructed more selectively for quercetin. As a result, a simple, sensitive and rapid new voltammetric method for the determination of antioxidants has been developed using the modified electrode.

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Determination of S(IV) Oxoanions at Poly[Ru(5-NO2-Phen)2Cl] Tetrapyridylporphyrin Glassy Carbon Modified Electrode

Electroanalysis ◽

10.1002/elan.201200038 ◽

2012 ◽

pp. n/a-n/a ◽

Cited By ~ 2

Author(s):

Paulina Dreyse ◽

Diego Quezada ◽

Jessica Honores ◽

María Jesús Aguirre ◽

Leonora Mendoza ◽

...

Keyword(s):

Modified Electrode ◽

Glassy Carbon ◽

Glassy Carbon Modified Electrode

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Simultaneous and selective electrochemical determination of hydroquinone, catechol and resorcinol at poly(1,5-diaminonaphthalene)/glassy carbon-modified electrode in different media

RSC Advances ◽

10.1039/c7ra13665j ◽

2018 ◽

Vol 8 (12) ◽

pp. 6346-6355 ◽

Cited By ~ 9

Author(s):

Khalid Mahmoud Hassan ◽

Abla Ahmed Hathoot ◽

Mohamed Fathi Abo oura ◽

Magdi Abdel Azzem

Keyword(s):

Cyclic Voltammetry ◽

Modified Electrode ◽

Glassy Carbon ◽

Square Wave Voltammetry ◽

Electrochemical Determination ◽

Electrochemical Behaviors ◽

Square Wave ◽

Wave Voltammetry ◽

Glassy Carbon Modified Electrode

Electrochemical behaviors of hydroquinone, catechol and resorcinol were examined at poly(1,5-diaminonaphthalene)/glassy carbon-modified electrode by cyclic voltammetry, square wave voltammetry and chronoamperometry techniques in different media.

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Voltammetric Determination of Mitomycin c Using a Chemically-Modified Glassy Carbon Electrode

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20050178 ◽

2005 ◽

Vol 70 (2) ◽

pp. 178-187 ◽

Cited By ~ 5

Author(s):

Wanyun Qu ◽

Hong Wang ◽

Kangbing Wu

Keyword(s):

Mitomycin C ◽

Glassy Carbon Electrode ◽

Modified Electrode ◽

Glassy Carbon ◽

Low Cost ◽

Direct Determination ◽

High Sensitivity ◽

Carbon Electrode ◽

Oxidation Peak

An electrochemical method for the direct determination of mitomycin c (MMC), based on a multi wall carbon nanotube (MWNT)-modified electrode, has been developed. A well-shaped and highly sensitive oxidation peak at 0.79 V was observed on the MWNT-modified electrode for MMC. Further studies show strong evidence that MWNT-modified electrode significantly enhances the sensitivity of determination of MMC since the oxidation peak current of MMC increases remarkably, compared with that with a bare glassy carbon electrode. All the experimental parameters such as pH, scan rate, accumulation conditions, have been examined. A sensitive linear voltammetric response for MMC was obtained over the concentration range of 2.5 × 10-7-1.0 × 10-4 mol/l; the detection limit is 8 × 10-8 mol/l. Compared with other methods, this new-proposed method possesses advantages such as high sensitivity, fast response, low cost and simplicity. Eventually, the proposed method has been successfully employed to detect MMC in urine samples.

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