Selective Determination of Uric Acid by Using a β-Cyclodextrin Modified Electrode

Zheng, Li; Wu, Shouguo; Lin, Xucong; Nie, Lei; Lei, Rui

doi:10.1002/1521-4109(200111)13:16<1351::aid-elan1351>3.0.co;2-f

Cited by 59 publications

(20 citation statements)

References 27 publications

(24 reference statements)

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“…Surface modifications are based on the immobilization of enzyme uricase, [6][7][8] or the modification of a UA sensing matrix layer. 9 On the other hand, activated electrodes, 10 diamonds 11 and carbon nanotube electrodes 12 have been employed as novel electrode materials.…”

Section: Introductionsupporting

confidence: 91%

Electrochemical Selective Detection of Uric Acid Using a Copper-modified Carbon Electrode

et al. 2011

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Section: Introductionsupporting

confidence: 91%

Electrochemical Selective Detection of Uric Acid Using a Copper-modified Carbon Electrode

et al. 2011

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“…The reason for this phenomenon may originate from the high concentration of UA in the interface of modified electrode due to the selective inclusion effect of β-CD. Since β-CD can readily include the neutral UA than AA monoanionic species at pH 7.0 [44]. Compared with curve B, the peak currents of AA and UA at SWCNTs/β-CD/GCE (curve C) was smaller than that of SWCNTs-β-CD/GCE, and its oxida tive potentials shifted positively.…”

Section: Electrochemical Sensor Of Aa and Ua By Swcnts-β-cd Modified Gcementioning

confidence: 99%

<i>β</i>-cyclodextrin Covalently Functionalized Single-Walled Carbon Nanotubes: Synthesis, Characterization and a Sensitive Biosensor Platform

Gao¹,

Cao²,

Song³

et al. 2011

JBNB

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In this study, we presented the preparation of β-cyclodextrin (β-CD) covalently functionalized single-walled carbon nanotubes (SWCNTs) and its application in modifying the solid glass carbon electrode (GCE). Cyclic voltammetry (CV) method was employed to evaluate the performance of the modified GCE. Solubility experiment indicated the conjugation of SWCNTs and β-CD, SWCNTs-β-CD with 8 wt% β-CD content could be well dispersed in water. High-resolution transmission electron microscopy (HRTEM) demonstrated that the aggregated SWCNTs bundle were effectively exfoliated to small bundle, even individual tube. The β-CD component was grafted on the side walls as well as tips of SWCNTs, and the grafted β-CD component was not uniformly coated on the surface of SWCNTs. The CV measurements indicated the performance of the GCE modified by SWCNTs-β-CD was better than that of the GCE modified by the hybrid of SWCNTs

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“…5 Its abnormal concentration level in urine and serum are symptoms of several diseases like gout, hyperuricaemia and Lesch-Nyhan syndrome. 6,7 For instance, the concentration of uric acid in the blood of patients suffering from gout increases up to 1 mmol L -1 , which is above the concentration of uric acid in blood for a healthy person. 5,8 According to literature, 8,9 the concentration of UA in serum is about 240-520 µmol L -1 and the urinary excretion is 1.49-4.46 mmol L -1 per 24 h for a healthy person.…”

Section: Introductionmentioning

confidence: 99%

“…Among them a widely used method is to coat the electrode with an ion-exchange membrane such as Nafion film, which is mainly employed to determine UA in the presence of AA at acid medium. 14,15 On the other hand, poly(3,4-dihydroxybenzaldehyde), 16 polypyrroledodecyl sulfate, 17 β-cyclodextrin, 6 carbon nanotube, 13 selfassembly monolayer of thiol 9 and clay modified electrodes 18 were used to determine UA or AA in the presence of the other without an ion-exchange membrane.…”

Section: Introductionmentioning

confidence: 99%

Micelle-mediated method for simultaneous determination of ascorbic acid and uric acid by differential pulse voltammetry

Reis¹,

Tarley²,

Kubota³

2008

J. Braz. Chem. Soc.

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O presente trabalho descreve uma metodologia analítica para determinação simultânea de ácido ascórbico (AA) e ácido úrico (AU) por voltametria de pulso diferencial empregando o surfactante catiônico cloreto de cetilpiridínio. Medidas voltamétricas de pulso diferencial realizadas em pH 7,0 revelaram que o meio micelar catiônico permite separar em 282 mV os picos de oxidação de AA e AU na mesma solução, valor suficiente para determinar ambas as espécies simultaneamente. Como em pH 7,0 o AA está mais ionizado que o AU, sua atração eletrostática em direção às micelas catiônicas, formadas sobre a superfície do eletrodo de carbono vítreo, é maior; desta forma, promove a diminuição no sobrepotencial e o aumento na taxa de transferência de elétrons. Foram construídas curvas de calibração para AA e AU na faixa de concentração de 4,70 até 220 µmol L -1 e 0,50 até 110 µmol L -1 . A metodologia proposta foi aplicada para a determinação de AA e AU em amostras de urina humana.The present work describes an analytical methodology for simultaneous determination of ascorbic acid (AA) and uric acid (UA) by differential pulse voltammetry employing the cationic surfactant, cetylpyridinium chloride. Differential pulse voltammetry measurements revealed that the cationic micellar media may separate the oxidation peak potentials of AA and UA present in the same solution by about 282 mV, which is enough to determine both species simultaneously. As in pH 7.0 the AA is more ionized than UA, its electrostatic attraction towards the cationic micelles formed onto the surface of glassy carbon electrode is higher, therefore, promoting a decrease in the overpotential and increasing the electron transfer rate. Calibration curves to AA and UA in the concentration range from 4.70 up to 220 µmol L -1 and 0.50 up to 110 µmol L -1 were built. The proposed methodology was applied for the simultaneous determination of AA and UA in human urine samples.Keywords: uric acid, ascorbic acid, differential pulse voltammetry, cationic surfactant, micelles IntroductionAscorbic acid (AA) and uric acid (UA) coexist in biological fluids such as blood and urine, 1 being in practical medicine, necessary to determine AA and UA simultaneously. Ascorbic acid (a water soluble vitamin C) plays a vital role in processes of oxidation and reduction in the human organism by participating in many metabolic reactions. 2 AA has also been used to prevent and treat the common cold, mental illness, infertility and cancer. 3 Moreover, ascorbic acid has also been used clinically in the treatment and prevention of scurvy. 4 Uric acid (2,6,8-trihydroxypurine, UA) is the primary product of purine metabolism in the human body and is formed in liver and tissues during the oxidation of aminopurines. 5 Its abnormal concentration level in urine and serum are symptoms of several diseases like gout, hyperuricaemia and Lesch-Nyhan syndrome. 6,7 For instance, the concentration of uric acid in the blood of patients suffering from gout increases up to 1 mmol L -1 , which is above the concentration ...

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Selective Determination of Uric Acid by Using a β-Cyclodextrin Modified Electrode

Cited by 59 publications

References 27 publications

Electrochemical Selective Detection of Uric Acid Using a Copper-modified Carbon Electrode

Electrochemical Selective Detection of Uric Acid Using a Copper-modified Carbon Electrode

<i>β</i>-cyclodextrin Covalently Functionalized Single-Walled Carbon Nanotubes: Synthesis, Characterization and a Sensitive Biosensor Platform

Micelle-mediated method for simultaneous determination of ascorbic acid and uric acid by differential pulse voltammetry

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Selective Determination of Uric Acid by Using a β-Cyclodextrin Modified Electrode

Cited by 59 publications

References 27 publications

Electrochemical Selective Detection of Uric Acid Using a Copper-modified Carbon Electrode

Electrochemical Selective Detection of Uric Acid Using a Copper-modified Carbon Electrode

&lt;i&gt;β&lt;/i&gt;-cyclodextrin Covalently Functionalized Single-Walled Carbon Nanotubes: Synthesis, Characterization and a Sensitive Biosensor Platform

Micelle-mediated method for simultaneous determination of ascorbic acid and uric acid by differential pulse voltammetry

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<i>β</i>-cyclodextrin Covalently Functionalized Single-Walled Carbon Nanotubes: Synthesis, Characterization and a Sensitive Biosensor Platform