3D-Printed graphene/polylactic acid electrode for bioanalysis: Biosensing of glucose and simultaneous determination of uric acid and nitrite in biological fluids

A simple and selective electrochemical method was investigated for the simultaneous determination of quercetin (Qu) and uric acid (UA) in aqueous media (citrate buffer solution, pH 4.0) on a glassy carbon electrode modified with graphene nanosheets as a sensing platform (GNSs/GCE). Cyclic voltammetry, transmission electron microscopy, and Fourier transform infrared spectroscopy were employed to characterize the nanostructure of the sensor. Separation of the oxidation peak potentials for Qu and UA was about 160 mV, and the anodic currents for the oxidation of both Qu and UA are greatly increased at GNSs/GCE, which makes it suitable for simultaneous determination of these compounds. The detection limits were 0.0011 and 0.0137 μmol/L for Qu and UA, respectively. The method was applied to the determination of Qu and UA in human blood serum and urine samples.

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Carbon-nanotube Modified Screen-printed Electrode for the Simultaneous Determination of Nitrite and Uric Acid in Biological Fluids Using Batch-injection Amperometric Detection

Electroanalysis ◽

10.1002/elan.201800189 ◽

2018 ◽

Vol 30 (8) ◽

pp. 1870-1879 ◽

Cited By ~ 7

Author(s):

Larissa P. Caetano ◽

Ana P. Lima ◽

Thiago F. Tormin ◽

Eduardo M. Richter ◽

Foued S. Espindola ◽

...

Keyword(s):

Uric Acid ◽

Carbon Nanotube ◽

Simultaneous Determination ◽

Biological Fluids ◽

Amperometric Detection ◽

Screen Printed Electrode ◽

Screen Printed

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Simultaneous Determination of Uric Acid and Xanthine Using a Poly(Methylene Blue) and Electrochemically Reduced Graphene Oxide Composite Film Modified Electrode

Journal of Analytical Methods in Chemistry ◽

10.1155/2014/984314 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

Gen Liu ◽

Wei Ma ◽

Yan Luo ◽

Deng-ming Sun ◽

Shuang Shao

Keyword(s):

Methylene Blue ◽

Uric Acid ◽

Graphene Oxide ◽

Composite Film ◽

Simultaneous Determination ◽

Reduced Graphene Oxide ◽

Modified Electrode ◽

Reduced Graphene ◽

Electrochemically Reduced Graphene Oxide

Poly(methylene blue) and electrochemically reduced graphene oxide composite film modified electrode (PMB-ERGO/GCE) was successfully fabricated by electropolymerization and was used for simultaneous determination of uric acid (UA) and xanthine (Xa). Based on the excellent electrocatalytic activity of PMB-ERGO/GCE, the electrochemical behaviors of UA and Xa were studied by cyclic voltammetry (CV) and square wave voltammetry (SWV). Two anodic sensitive peaks at 0.630 V (versus Ag/AgCl) for UA and 1.006 V (versus Ag/AgCl) for Xa were given by CV in pH 3.0 phosphate buffer. The calibration curves for UA and Xa were obtained in the range of 8.00 × 10−8~4.00 × 10−4 M and 1.00 × 10−7~4.00 × 10−4 M, respectively, by SWV. The detection limits for UA and Xa were3.00×10-8 M and5.00×10-8 M, respectively. Finally, the proposed method was applied to simultaneously determine UA and Xa in human urine with good selectivity and high sensitivity.

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