scholarly journals A Promising Electrochemical Platform for Dopamine and Uric Acid Detection Based on a Polyaniline/Iron Oxide-Tin Oxide/Reduced Graphene Oxide Ternary Composite

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5869
Author(s):  
Daria Minta ◽  
Adam Moyseowicz ◽  
Stanisław Gryglewicz ◽  
Grażyna Gryglewicz

A ternary polyaniline/Fe2O3-SnO2/reduced graphene oxide (PFSG) nanocomposite was prepared using a simple two-step hydrothermal treatment. The composite was applied as a glassy carbon electrode modifier (GCE) to enhance dopamine (DA) and uric acid (UA) detection. The ternary PFSG composite was compared with its binary precursor Fe2O3-SnO2/reduced graphene oxide (FSG). The influence of the modified GCE electrodes on their performance as a sensing platform was determined. GCE/PFSG showed better sensing parameters than GCE/FSG due to the introduction of polyaniline (PANI), increasing the electrocatalytic properties of the electrode towards the detected analytes. GCE/PFSG enabled the detection of low concentrations of DA (0.076 µM) and UA (1.6 µM). The peak potential separation between DA and UA was very good (180 mV). Moreover, the DA oxidation peak was unaffected even if the concentration of UA was ten times higher. The fabricated sensor showed excellent performance in the simultaneous detection with DA and UA limits of detection: LODDA = 0.15 µM and LODUA = 6.4 µM, and outstanding long-term stability towards DA and UA, holding 100% and 90% of their initial signals respectively, after one month of use.

Carbon ◽  
2018 ◽  
Vol 139 ◽  
pp. 226-233 ◽  
Author(s):  
J.L. Gómez-Urbano ◽  
J.L. Gómez-Cámer ◽  
C. Botas ◽  
N. Díez ◽  
J.M. López del Amo ◽  
...  

Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4427
Author(s):  
Daria Minta ◽  
Zoraida González ◽  
Piotr Wiench ◽  
Stanisław Gryglewicz ◽  
Grażyna Gryglewicz

Gold nanoparticles (AuNPs) were homogeneously electrodeposited on nitrogen-doped reduced graphene oxide (N-rGO) to modify a glassy carbon electrode (GCE/N-rGO-Au) in order to improve the simultaneous detection of dopamine (DA), ascorbic acid (AA), and uric acid (UA). N-rGO was prepared by the hydrothermal treatment of graphene oxide (GO) and urea at 180 °C for 12 h. AuNPs were subsequently electrodeposited onto the surface of GCE/N-rGO using 1 mM HAuCl4 solution. The morphology and chemical composition of the synthesized materials were characterized by field-emission scanning electron microscopy and X-ray photoelectron spectroscopy. The electrochemical performance of the modified electrodes was investigated through cyclic voltammetry and differential pulse voltammetry measurements. Compared to GCE/rGO-Au, GCE/N-rGO-Au exhibited better electrochemical performance towards the simultaneous detection of the three analytes due to the more homogeneous distribution of the metallic nanoparticles as a result of more efficient anchoring on the N-doped areas of the graphene structure. The GCE/N-rGO-Au-based sensor operated in a wide linear range of DA (3–100 µM), AA (550–1500 µM), and UA (20–1000 µM) concentrations with a detection limit of 2.4, 58, and 8.7 µM, respectively, and exhibited satisfactory peak potential separation values of 0.34 V (AA-DA), 0.20 V, (DA-UA) and 0.54 V (AA-UA). Remarkably, GCE/N-rGO-Au showed a very low detection limit of 385 nM towards DA, not being susceptible to interference, and maintained 90% of its initial electrochemical signal after one month, indicating an excellent long-term stability.


2015 ◽  
Vol 08 (03) ◽  
pp. 1540004 ◽  
Author(s):  
Qiaofang Shi ◽  
Guowang Diao ◽  
Shaolin Mu

A given amount of gold is electrodeposited on the reduced graphene oxide (RGO)/glassy carbon (GC) electrodes to form Au /RGO/GC electrodes, which are carried out at different potentials. The Au /RGO/GC electrode with Au loading of 250 μg cm-2 prepared at a constant potential of -0.30 V exhibits the best electrocatalytic activity to glucose oxidation in alkaline solutions because of homogeneous dispersion of gold nanoparticles with smaller sizes. This electrode shows long-term stability, rapid charge transfer ability, and higher current density compared to other gold electrodes reported previously.


2021 ◽  
Vol 83 (3) ◽  
pp. 85-92
Author(s):  
Azleen Rashidah Mohd Rosli ◽  
Farhanini Yusoff ◽  
Saw Hong Loh ◽  
Hanis Mohd Yusoff ◽  
Muhammad Mahadi Abdul Jamil ◽  
...  

A magnetic nanoparticles/reduced graphene oxide modified glassy carbon electrode (MNP/rGO/GCE) was fabricated via one-step facile synthesis route for the simultaneous determination of ascorbic acid (AA), dopamine (DA), along with uric acid (UA). A series of diseases and disorders has been associated with irregular levels of these respective analytes, thus early detection is highly crucial. Physical and electrochemical characterization of the modified electrode was conducted by using Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) analysis, X-Ray Diffraction (XRD) analysis and Brauneur-Emmet-Teller (BET), Cyclic Voltammetry (CV) and Electron Impedance Spectroscopy (EIS). The results obtained confirmed the formation of MNP/rGO composite. Differential pulse voltammetry (DPV) of MNP/rGO/GCE displays three well-defined peaks which associated to AA, DA and UA, respectively. The response towards DA is linear in the concentration range of 15 nM to 100 µM with a detection limit of 0.19 nM while a response to AA and UA is also linear in the concentration range of 10 µM to 100 µM with a limit of detection 0.22 µM and 45 nM respectively. The proposed modified electrode offers a good response towards simultaneous detection of three different electroactive species with excellent electron transfer rate, great capacitance and ideal diffusive control behavior.


2020 ◽  
Vol 56 (95) ◽  
pp. 15068-15071
Author(s):  
Fangfang Dai ◽  
Risheng Yu ◽  
Ruobing Yi ◽  
Jian Lan ◽  
Rujie Yang ◽  
...  

A simple way to fabricate pure rGO membranes shows ultrahigh water permeance and excellent multivalent metal ion rejection, as well as long-term stability.


Nanomaterials ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 602 ◽  
Author(s):  
Szustakiewicz ◽  
Kołsut ◽  
Leniart ◽  
Lewandowski

In this study, we report a universal approach allowing the non-covalent deposition of gold nanoparticles on reduced graphene oxide surface in a controlled fashion. We used a modified Hummers method to obtain graphene oxide, which then underwent surficial functionalization with carboxyl moieties coupled with simultaneous reduction. Nanoparticles were synthesized ex-situ and capped with a thiolated poly-ethylene glycol (PEG) ligand. The interactions between the surface of modified graphene oxide and nanoparticle ligands enabled the formation of stable hybrid graphene-nanoparticles materials in the aqueous phase. Using this technique, we were able to cover the surface of graphene with gold nanoparticles of different shapes (spheres, rods, triangles, stars, and bipyramids), broad range of sizes (from 5 nm to 100 nm) and controlled grafting densities. Moreover, materials obtained with this strategy exhibited long-term stability, which coupled with the versatility and facility of preparation, makes our technique appealing in the light of increasing demand for new graphene-based hybrid nanostructures.


Sensors ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 1256 ◽  
Author(s):  
Zouhour Hsine ◽  
Salma Bizid ◽  
Rym Mlika ◽  
Hélène Sauriat-Dorizon ◽  
Ayoub Haj Said ◽  
...  

In this study, an efficient and simple designed nanohybrid created for individual and simultaneous detection of ascorbic acid (AA), dopamine (DA) and uric acid (UA). This nanohybrid is a combination of chemical reduced graphene oxide (CRGO) and redox poly(para-phenylene) (Fc-ac-PP) modified in a lateral position with ferrrocenyl group CRGO/Fc-ac-PPP. The CRGO/Fc-ac-PPP nanohybrid demonstrated a synergistic effect resulting in a large conductivity, surface area and catalytic properties provided by the redox attached ferrocene. Moreover, this nanocomposite is able to detect individually as well as simultaneously AA, DA and UA in a co-existence system with defined and separated redox peaks oxidation. The linear response ranges for AA, DA and UA, when detected simultaneously, are 0.1–10000 μM, 0.0001–1000 μM and 0.1–10000 μM, respectively, and the detection limits (S/N = 3) are 0.046 μM, 0.2 nM and 0.013 μM, respectively. The proposed sensor shown satisfactory results when applied to real spiked urine samples for measuring the abnormal high or lowconcentration of AA, DA and UA in vivo.


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