Non-enzymatic determination of purine nucleotides using a carbon dot modified glassy carbon electrode

A novel composite was firstly synthesized by compositing graphenes (G) and carbon nanotubes (CNTs) and then a new composite modified electrode (G/CNTs/GCE) was prepared by coating the resulting composite on the surface of the glassy carbon electrode (GCE). The composite modified electrode G/CNTs/GCE showed great electrochemical activities which were studied by sensitive determining the electrochemistry behaviors of uric acid (UA). It revealed when the concentration range of UA changed from 1×10-7 mol/L to 1×10-3 mol/L, the peak currents had linear relationship with the concentration of UA in the phosphate buffer solution (PBS) which the value of pH is 7.0. And the linear equation is ip (μA) = 21.55C+28.94 (C: mmol/L), with the related coefficient 0.9964.

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Electrochemical determination of hydrogen peroxide at glassy carbon electrode modified with palladium nanoparticles

Journal of the Serbian Chemical Society ◽

10.2298/jsc120619122k ◽

2013 ◽

Vol 78 (5) ◽

pp. 701-711 ◽

Cited By ~ 12

Author(s):

Addisu Kitte ◽

Desalegn Assresahegn ◽

Refera Soreta

Keyword(s):

Hydrogen Peroxide ◽

Glassy Carbon Electrode ◽

Glassy Carbon ◽

Palladium Nanoparticles ◽

Phosphate Buffer Solution ◽

Reference Electrode ◽

Electrochemical Determination ◽

Carbon Electrode ◽

Buffer Solution ◽

Solution Ph

We report here the modification of glassy carbon electrode (GCE) with palladium nanoparticles and palladium film. The response to hydrogen peroxide on the modified electrode was examined using cyclic voltammetry and amperometry (at -0.2 V vs Ag/AgCl reference electrode in the phosphate buffer solution pH 7.4). The palladium film and palladium nanoparticle modified GCE showed a linear response to hydrogen peroxide in the concentration range between 10 ?M to 14 mM and 1 ?M to 14 mM with detection limit of 6.79 ?M and 0.33 ?M, respectively.

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Sensitive Determination of Epinephrine in the Presence of Ascorbic Acid at Poly(diphenylamine sulfonic acid) Modified Sensor

Sensor Letters ◽

10.1166/sl.2020.4228 ◽

2020 ◽

Vol 18 (4) ◽

pp. 253-258

Author(s):

Gamze Erdoğdu

Keyword(s):

Ascorbic Acid ◽

Sulfonic Acid ◽

Limit Of Detection ◽

Phosphate Buffer Solution ◽

Differential Pulse ◽

Buffer Solution ◽

Sensitive Determination ◽

Pulse Voltammetry ◽

Modified Sensor

A sensitive and simple modified sensor was prepared by electrodeposition of diphenylamine sulfonic acid (DPSA) to the glassy carbon electrode surface by cyclic voltammetry (CV) technique. The electrooxidation of epinephrine (EP) was accomplished by CV and differential pulse voltammetry at poly(DPSA) modified sensor. As a result of the findings, the current values were enhanced and both substances were separated at the modified sensor compared to the bare electrode. There was linearly between the oxidation current and concentration of EP from 0.2 to 100 μM in phosphate buffer solution at pH 7.0. The limit of detection was 5.0 nM and the sensitivity was 0.4205 μA/μM. The determination of EP was successfully and satisfactorily carried out in real samples such as human blood serum and urine at the poly(DPSA) sensor. To the best knowledge of this work, this is the first study that detect the EP in the presence of ascorbic acid at poly(DPSA) sensor in the literature.

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Coated Carbon Nanotubes at Nano Copper Modified GCE for Simultaneous Determination of Dopamine and Uric Acid

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.600.238 ◽

2012 ◽

Vol 600 ◽

pp. 238-241

Author(s):

Xiao Ling Qiang ◽

Jian Fei Xia ◽

Zong Hua Wang ◽

Yan Zhi Xia ◽

Fei Fei Zhang ◽

...

Keyword(s):

Carbon Nanotubes ◽

Uric Acid ◽

Phosphate Buffer Solution ◽

Carbon Electrode ◽

Cu Nanoparticles ◽

Buffer Solution ◽

Solution Ph ◽

Electrochemically Deposited ◽

Coated Carbon

Copper (Cu) nanoparticles have been electrochemically deposited onto the glassy carbon electrode (GCE) surface by potentiostatic deposition method and then carbon nanotubes (CNTs) was dropped on the nano-Cu modified electrode surface to get a CNTs/nano-Cu/GCE electrode. The CNTs/nano-Cu/GCE has shown much higher electrocatalytic activity than the CNTs/GCE towards the oxidation of dopamine (DA) and uric acid (UA) in a phosphate buffer solution (pH 6.9). It can be applied to determine DA and UA with satisfactory results.

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The Application of Glassy Carbon Electrode Modified by Multi-Walled Carbon Nanotubes for the Fast Determination of Hydroquinone in Wastewater

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.1160 ◽

2014 ◽

Vol 955-959 ◽

pp. 1160-1166

Author(s):

Shao Hua Li ◽

Ying Ying Zhao ◽

Jun Qing Yang ◽

Guo Yan Zhang ◽

Ju Rui Qi

Keyword(s):

Carbon Nanotubes ◽

Glassy Carbon Electrode ◽

Glassy Carbon ◽

Phosphate Buffer Solution ◽

Differential Pulse ◽

Carbon Electrode ◽

Buffer Solution ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

A novel multi-walled carbon nanotubes (MWCNTs)-modified glassy carbon electrode (GCE) with excellent stability, repeatability and anti-interference was synthesized and it exhibited an electrocatalytic signal for hydroquinone (HQ) compared to bare GCE, which suggested that the presence of MWCNTs efficiently enhances electron transfer. Various parameters such as pH, modifier volume, and scan rate were optimized using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. Under optimum conditions, linear responses for HQ in 0.1mol·L-1 phosphate buffer solution of pH 6.0 were obtained in the range of 5×10-6 mol·L-1 to 2×10-4 mol·L-1 with detection limits of 2.7×10-6 mol·L-1 (signal-to-noise ratio of 3). Such MWCNTs-modified GCE was successfully applied for the determination of hydroquinone in simulated water samples and can be developed for the the detection of HQ.

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Electrochemical Determination of Albendazole at Glassy Carbon Electrode

Journal of AOAC International ◽

10.5740/jaoacint.16-0009 ◽

2016 ◽

Vol 99 (6) ◽

pp. 1522-1526 ◽

Cited By ~ 2

Author(s):

Jayant I Gowda ◽

Rahul B Kantikar ◽

Devaraddi G Harakuni ◽

Kirankumar Y Jadhav ◽

Vinay C Chanagoudar ◽

...

Keyword(s):

Glassy Carbon Electrode ◽

Glassy Carbon ◽

Saturated Calomel Electrode ◽

Phosphate Buffer Solution ◽

Electrochemical Determination ◽

Carbon Electrode ◽

Buffer Solution ◽

Solution Ph ◽

Electrochemical Parameters ◽

Anodic Peak Current

Abstract In this article, the electrochemical behavior on a glassy carbon electrode (GCE) was investigated and the electrochemical parameters of albendazole (ALB) were calculated. ALB effectively accumulated on the GCE surface and caused a pair of redox peaks at around 1.095 V and 1.028 V and an oxidation peak at 0.844 V (versus saturated calomel electrode) in 0.2 M phosphate buffer solution (pH 3.0). Under optimized conditions, the anodic peak current was linear to the ALB concentration the range of 1.5 × 10−7 M to 4.0 × 10−5 M. The regression equation was: Ipa (10−6 A) = 0.79 [ALB] (μM) + 0.84 (R2 = 0.982). The detection limit 6.08 × 10−8 M was obtained. The proposed method was successfully used to determine ALB content in tablet samples, with satisfactory results.

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Poly (DL-valine) electro-polymerized carbon nanotube paste sensor for determination of antihistamine drug cetirizine

Journal of Electrochemical Science and Engineering ◽

10.5599/jese.934 ◽

2020 ◽

Author(s):

Tigari Girish ◽

Jamballi G. Manjunatha ◽

Pemmatte A. Pushpanjali ◽

Nambudumada S. Prinith ◽

Doddarasinakere K. Ravishankar ◽

...

Keyword(s):

Carbon Nanotube ◽

Organic Molecules ◽

Phosphate Buffer Solution ◽

Multiwalled Carbon Nanotube ◽

Buffer Solution ◽

Solution Ph ◽

Multiwalled Carbon ◽

Accumulation Time ◽

Antihistamine Drug

Poly (DL-valine) modified multiwalled carbon nanotube paste sensor (PVLMCNTPS) was prepared by electro-polymerization route. PVLMCNTPS and bare multiwalled carbon nanotube paste sensor (BMCNTPS) morphologies and sensing properties for cetirizine (CTZ) were confirmed through a field emission scanning electron microscope (FE-SEM) and electrochemical studies, respectively. In contrast to BMCNTPS, PVLMCNTPS surface composite creates an electrocatalytic impact on the oxidation of CTZ. PVLMCNTPS properties were optimized using parameters such as accumulation time, number of polymerization cycles, solution pH, and scan rate. The optimized PVLMCNTPS was applied for the determination of cetirizine in 0.1 M phosphate buffer solution (PBS) of pH 7.0, using cyclic voltammetry (CV). It is shown that PVLMCNTPS provided analytical linearity from 2.0 to 80 µM, with a detection limit of 0.11 µM for CTZ determination. PVLMCNTPS is found highly selective for CTZ in presence of some interfering organic molecules. The stable and selective PVLMCNTPS was applied for CTZ determination in pharmaceutical pills with satisfactory results.

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Electrochemical Polymerised Graphene Paste Electrode and Application to Catechol Sensing

The Open Chemical Engineering Journal ◽

10.2174/1874123101913010081 ◽

2019 ◽

Vol 13 (1) ◽

pp. 81-87 ◽

Cited By ~ 4

Author(s):

Jamballi G. Manjunatha

Keyword(s):

Modified Electrode ◽

Limit Of Detection ◽

Phosphate Buffer Solution ◽

Sample Pretreatment ◽

Differential Pulse ◽

Buffer Solution ◽

Solution Ph ◽

Graphene Paste Electrode ◽

Paste Electrode

Objective: To build up an advantageous strategy for sensitive determination of catechol (CC), a poly (proline) modified graphene paste electrode (PPMGPE) was fabricated and used as a voltammetric sensor for the determination of CC. Methods: The performance of the modified electrode was studied using cyclic voltammetric (CV) and differential pulse voltammetric method (DPV). The modified electrode was characterized by CV and DPV. The surface of the modified electrode was examined by FESEM. The electrochemical behavior of CC in phosphate buffer solution (pH 7.5) was inspected using bare graphene paste electrode (BGPE) and PPMGPE. Results & Conclusion: The PPMGPE shows a lower limit of detection, calculated to be 8.7×10–7mol L−1 (S/N=3). This modified electrode was applied successfully for the determination of CC in water samples without applying any sample pretreatment.

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Electrochemical sensor for determination of hydroxylamine using functionalized Fe3O4 nanoparticles and graphene oxide modified screen-printed electrode

Journal of Electrochemical Science and Engineering ◽

10.5599/jese.1145 ◽

2021 ◽

Author(s):

Hamed Tashakkorian ◽

Behnaz Aflatoonian ◽

Peyman Mohammadzadeh Jahani ◽

Mohammad Reza Aflatoonian

Keyword(s):

Graphene Oxide ◽

Electrochemical Sensor ◽

Fe3o4 Nanoparticles ◽

Phosphate Buffer Solution ◽

Electrochemical Process ◽

Screen Printed Electrode ◽

Buffer Solution ◽

Solution Ph ◽

Screen Printed

A simple strategy for determination of hydroxylamine based on Fe3O4 nanoparticles functionnalized by [2-(4-((3-(trimethoxysilyl)propylthio)methyl)1-H1,2,3-triazol-1-yl)aceticacid] (FNPs) and graphene oxide (GO) modified screen-printed electrode (SPE), denoted as (Fe3O4 FNPs/GO/SPE), is reported. The electrochemical behavior of hydroxylamine was investigated at Fe3O4FNPs/GO/SPE by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry (CHA) techniques in phosphate buffer solution (pH 7.0). Fe3O4 FNPs/GO/SPE as a novel electrochemical sensor exhibited catalytic activity toward the oxidation of hydroxylamine. The potential of hydroxylamine oxidation was shifted to more negative potentials, and its oxidation peak current increased on the modified electrode, also indicating that under these conditions, the electrochemical process is irreversible. The electrocatalytic current of hydroxylamine showed a good relationship in the concentration range of 0.05–700.0 μM, with a detection limit of 10.0 nM. The proposed electrode was applied for the determination of hydroxylamine in water samples, too.

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Sensitive and Simultaneous Determination of Hydroquinone and Catechol in Water Using an Anodized Glassy Carbon Electrode with Polymerized 2-(Phenylazo) Chromotropic Acid

Journal of Chemistry ◽

10.1155/2019/2327064 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Miao Zhang ◽

Chuang-ye Ge ◽

Ya-feng Jin ◽

Liang-bin Hu ◽

Hai-zhen Mo ◽

...

Keyword(s):

Glassy Carbon Electrode ◽

Glassy Carbon ◽

Environmental Pollutants ◽

Phosphate Buffer Solution ◽

Chromotropic Acid ◽

Carbon Electrode ◽

Mixed Solution ◽

Buffer Solution ◽

Recovery Method

Hydroquinone (HQ) and catechol (CT) are considered as environmental pollutants with high toxicity. We have developed a simple electrochemical sensor using an anodized glassy carbon electrode modified with a stable 2-(phenylazo) chromotropic acid- (CH-) conducting polymer (PCH/AGCE). The PCH/AGCE sensor showed good electrocatalytic activity and reversibility towards the redox of HQ and CT in phosphate buffer solution (PBS, pH 7.0). The cyclic voltammetry (CV) in mixed solution of HQ and CT showed that the oxidation peaks of them became well resolved with a peak separation of 0.1 V. The detection limits of HQ and CT were 0.044 and 0.066 μM, respectively, in a wide linear response range of 1–300 μM for both. Moreover, the sensor displayed an excellent selectivity in the presence of common interferences. This study provided a simple, sensitive, and high recovery method for simultaneous and quantitative determination of HQ and CT in aqueous medium.

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