Determination of oxalic acid in spinach with carbon nanotubes-modified electrode

Zheng, Yi; Yang, Changzhu; Pu, Weihua; Zhang, Jingdong

doi:10.1016/j.foodchem.2008.11.021

Cited by 55 publications

(29 citation statements)

References 31 publications

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“…According to Anson's equation [35]: Q=2nFAD 1/2 ct 1/2 /π 1/2 + Q dl +nFΓ, and by using the effective electrode area (A) of 0.42 cm 2 , the diffusion coefficient (D) was calculated as 4.39×10 −4 cm 2 s −1 . The result was larger than a previous reported value of 1.16×10 −4 cm 2 s −1 [14], which indicated a faster diffusion process of OA on GR/CILE than that of multiwalled carbon nanotube-modified glassy carbon electrode (MWCNT/GCE).…”

Section: Chronocoulometric Experimentscontrasting

confidence: 73%

“…The detection limit was estimated to be 0.48 μM (S/N=3), which was calculated by the equation: C L =KS o /S, where C L is the detection limit, K is a constant related to the confidence level, according to the suggestion of IUPAC, K=3 (99 % confidence), S o is the standard deviation of the blank measurements (N=9) and S is the slope of the calibration curve. The result was smaller than the previous reported values of 6.2 μM by HPLC [2], 0.2 mM on palladium nanoparticleloaded carbon nanofiber composites-modified carbon paste electrode (Pd/CNF-CPE) [7], 0.09 mM on a bienzymatic amperometric biosensor [9], 12.0 μM on MWCNT/GCE [14], 0.51 mM on GCE [17] and 0.05 mM on graphitepolystyrene composite electrode [37].…”

Section: Chronocoulometric Experimentscontrasting

confidence: 68%

“…One is the enzymatic method that is the application of various enzymes for reaction with OA and electrochemical detection of the product [9,10]. Another is the direct electrooxidation of OA on different working electrodes such as platinum, gold, borondoped diamond electrode [11][12][13] or chemically modified electrodes such as carbon nanotube [14], SiO 2 /SnO 2 mixed oxide [15] -modified electrode. Ferro et al investigated the electrooxidation of OA on different electrode materials [16].…”

Section: Introductionmentioning

confidence: 99%

“…The electrochemical oxidation of OA at different electrode materials has been reported [11][12][13][14][15][16][17][18]. But to the best of our knowledge, there is no report on OA oxidation and determination using a GR-modified CILE, which exhibits attractive performances for the sensitive OA detection with excellent voltammetric response.…”

Section: Introductionmentioning

confidence: 99%

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Sensitive electrochemical determination of oxalic acid in spinach samples by a graphene-modified carbon ionic liquid electrode

Cheng

You

Sha³

et al. 2014

Ionics

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In this paper, a new electrochemical oxalic acid (OA) sensor based on graphene (GR)-modified carbon ionic liquid electrode (CILE) was proposed. The GR nanosheets were deposited on the surface of CILE by electroreduction with graphene oxide as precursor and electrocatalytic oxidation of OA on GR/CILE was further investigated. As compared with that of bare CILE, the oxidation peak current of OA on GR/CILE were greatly improved with the decrease of the oxidation potential. Electrochemical parameters of the electrooxidation of OA were calculated. Under the selected conditions, the oxidation peak currents increased with OA concentration in the range from 8.0 μM to 6.0 mM with the detection limit as 0.48 μM (3σ). The proposed method exhibited higher sensitivity and wider linear range, which was applied to determination of OA concentration in spinach samples with satisfactory results.

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Section: Chronocoulometric Experimentscontrasting

confidence: 73%

Section: Chronocoulometric Experimentscontrasting

confidence: 68%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Sensitive electrochemical determination of oxalic acid in spinach samples by a graphene-modified carbon ionic liquid electrode

Cheng

You

Sha³

et al. 2014

Ionics

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“…Prior to use, the purification process referred to the literature [26]. BTA in chemical grade was obtained from Shanghai Reagent Co., China.…”

Section: Reagents and Chemicalsmentioning

confidence: 99%

Voltammetric behaviors of an emerging pollutant benzotriazole on multiwall carbon nanotubes (MWNTs)—Nafion modified electrode in various pH mediums

Zheng

Zhang

et al. 2016

Ionics

Self Cite

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The electrochemical behaviors of an emerging pollutant, benzotriazole (BTA), at multiwall carbon nanotubes and Nafion modified glassy carbon electrode (MWNTsNafion/GCE) were investigated systematically. The electrochemical reduction of BTA was significantly improved by MWNTs-Nafion compared to bare GCE, ascribed to the excellent adsorption capacity and electrocatalytic activity of MWNTs. BTA presented well-defined reduction peaks only at pH <3.0, suggesting the involvement of lots of protons in the reduction process. Peak potential shifted negatively and peak current decreased significantly with pH increase. BTA showed various UV-Vis absorption spectra in acidic and alkaline mediums. Cathodic peak current increased linearly with square root of sweep rate as well as with the concentration of BTA from 3.0 × 10 −6 to 1.6 × 10 −4 mol L −1 . This suggests a diffusion-controlled and irreversible electrode process.Diffusion coefficient of BTA on MWNTs-Nafion/GCE was obtained as 2.67 × 10 −2 cm 2 s −1 with four orders of magnitude larger than that on GCE. MWNTs-Nafion/GCE showed a good selectivity between BTA and O 2 but poor selectivity between BTA and tolyltriazole.

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Electrodeposition of PdAu Alloy Nanoparticles on Ionic Liquid Functionalized Graphene Film for the Voltammetric Determination of Oxalic Acid

Shang¹,

Zhao²,

Zeng³

2013

Electroanalysis

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An ionic liquid functionalized graphene film was prepared and PdAu nanoparticles (NPs) were electrodeposited on it. The PdAu NPs were characterized by various methods and they showed the features of alloys. In 0.2 M H2SO4 solution, oxalic acid (OA) exhibited a sensitive anodic peak at the resulting electrode at about 1.1 V (vs. SCE), and the peak current was linear to OA concentration in the range of 5–100 µM with a sensitivity of 45.5 µA/mM. The detection limit was 2.7 µM (S/N=3). The electrode was successfully applied to the determination of OA in real sample.

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Determination of oxalic acid in spinach with carbon nanotubes-modified electrode

Cited by 55 publications

References 31 publications

Sensitive electrochemical determination of oxalic acid in spinach samples by a graphene-modified carbon ionic liquid electrode

Sensitive electrochemical determination of oxalic acid in spinach samples by a graphene-modified carbon ionic liquid electrode

Voltammetric behaviors of an emerging pollutant benzotriazole on multiwall carbon nanotubes (MWNTs)—Nafion modified electrode in various pH mediums

Electrodeposition of PdAu Alloy Nanoparticles on Ionic Liquid Functionalized Graphene Film for the Voltammetric Determination of Oxalic Acid

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