Metallic Film Modified Screen-Printed Carbon Electrode for Determination of 17α-Methyltestosterone

17α-methyltestosterone (MT) is a synthetic androgen. It is used widely for inducing an all-male population of Nile tilapia (Oreochromis niloticus). In this work, the detection of MT was conducted using screen-printed carbon electrodes (SPCE). These were a bare electrode, a bismuth modified electrode (Bi-SPCE) and an antimony modified electrode (Sb-SPCE). The successful electrode modification was confirmed by scanning electron microscopy. The electroanalytical performance of the SPCE modified electrodes for MT detection was examined by cyclic voltammetry. The highest active surface area of 1.073x10-4 cm2 was obtained on Sb-SPCE. This indicates that Sb-SPCE can enhance the sensitivity of MT detection better than the bare-SPCE and the Bi-SPCE. The Sb-SPCE showed a linear response for MT concentrations ranging from 2 to 8 mg.L-1. The sensitivity obtained from the slope of a calibration curve was -0.452 mA.mol-1.L-1 in a Britton-Robinson buffer pH 4.0 containing Sb 16 mg.L-1 with deposition potential and deposition time of 1 V and 90 seconds, respectively. A linear relationship between the square root of the scan rate and the peak current revealed that mass transfer of MT to the electrode was driven by a diffusion mechanism. The limit of detection was found to be 1 mg.L-1.

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Laccase Electrochemical Biosensor Based on Graphene-Gold/Chitosan Nanocomposite Film for Bisphenol A Detection

Current Analytical Chemistry ◽

10.2174/1573411015666190117114804 ◽

2020 ◽

Vol 16 (5) ◽

pp. 570-579

Author(s):

Fuzi M. Fartas ◽

Jaafar Abdullah ◽

Nor A. Yusof ◽

Yusran Sulaiman ◽

Mohd I. Saiman ◽

...

Keyword(s):

Bisphenol A ◽

Electrochemical Biosensor ◽

Limit Of Detection ◽

Modified Electrodes ◽

Electrochemical Performances ◽

Carbon Electrode ◽

Screen Printed Carbon Electrode ◽

Laccase Enzyme ◽

Bisphenol A Detection ◽

Screen Printed

Background: Bisphenol A (BPA) is considered one of the most common chemicals that could cause environmental endocrine disrupting. Therefore, there is an increasing demand for simple, rapid and sensitive methods for BPA detection that result from BPA leaching into foods and beverages from storage containers. Herein, a simple laccase electrochemical biosensor was developed for the determination of BPA based on Screen-Printed Carbon Electrode (SPCE) modified graphenegold/ chitosan. The synergic effect of graphene-gold/chitosan nanocomposite as electrode modifier greatly facilitates electron-transfer processes between the electrolyte and laccase enzyme, thus leads to a remarkably improved sensitivity for bisphenol A detection. Methods: In this study, laccase enzyme is immobilized onto the Screen-Printed Carbon Electrode (SPCE) modified Graphene-Decorated Gold Nanoparticles (Gr-AuNPs) with Chitosan (Chit). The surface structure of nanocomposite was studied using different techniques including Field Emission Scanning Microscopy (FESEM), TRANSMISSION Electron Microscopy (TEM), Raman spectroscopy and Energy Dispersive X-ray (EDX). Meanwhile, the electrochemical performances of the modified electrodes were studied using Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV). Results: The developed laccase biosensor offered excellent analytical performance for the detection of BPA with a sensitivity of 0.271 μA/μM and Limit of Detection (LOD) of 0.023 μM, respectively. Moreover, the constructed biosensor showed good reproducibility, selectivity and stability towards BPA. The sensor has been used to detect BPA in a different type of commercial plastic products as a real sample and satisfactory result was obtained when compared with the HPLC method. Conclusion: The proposed electrochemical laccase biosensor exhibits good result which is considered as a promising candidate for a simple, rapid and sensitive method especially in the resource- limited condition.

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Surface Enhanced CdSe/ZnS QD/SiNP Electrochemical Immunosensor for the Detection of Mycobacterium Tuberculosis by Combination of CFP10-ESAT6 for Better Diagnostic Specificity

Materials ◽

10.3390/ma13010149 ◽

2019 ◽

Vol 13 (1) ◽

pp. 149 ◽

Cited By ~ 5

Author(s):

Noremylia Mohd Bakhori ◽

Nor Azah Yusof ◽

Jaafar Abdullah ◽

Helmi Wasoh ◽

Siti Khadijah Ab Rahman ◽

...

Keyword(s):

Modified Electrode ◽

Limit Of Detection ◽

Active Surface ◽

Differential Pulse ◽

Electrochemical Immunosensor ◽

Enzyme Linked Immunosorbent Assay ◽

Active Surface Area ◽

High Electron ◽

Relative Standard ◽

Antigen Antibody

In this study, an electrochemical immunosensor was introduced for the detection of tuberculosis (TB) via utilization of a modified electrode containing a quantum dot (CdSe/ZnS QD) and functionalized silica nanoparticles (SiNPs) on screen-printed carbon electrode (SPCE) CdSe/ZnS QD/SiNPs/SPCE, by employing indirect enzyme-linked immunosorbent assay (ELISA). Here, the fabricated electrode was linked to the biocatalytic action of enzyme catalase through antigen–antibody binding for the detection of the antigen (CFP10–ESAT6) by means of producing a differential pulse voltammetry (DPV) current. The characterization and cyclic voltammetry (CV) of the modified electrode showed good electrochemical behavior and enhanced high electron transfer between the electrode and analyte. Moreover, the active surface area was 4.14-fold higher than the bare SPCE. The developed method showed high selectivity towards CFP10–ESAT6 compared with the other TB proteins. The detection of CFP10–ESAT6 also showed a linear response towards different concentrations of CFP10–ESAT6 with R2 = 0.9937, yielding a limit of detection (LOD) of as low as 1.5 × 10−10 g/mL for a linear range of 40 to 100 ng/mL of CFP10–ESAT6 concentration. The proposed method showed good reproducibility of target analyte with a relative standard deviation of 1.45%.

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Development of Highly Sensitive Immunosensor for Clenbuterol Detection by Using Poly(3,4-ethylenedioxythiophene)/Graphene Oxide Modified Screen-Printed Carbon Electrode

Sensors ◽

10.3390/s18124324 ◽

2018 ◽

Vol 18 (12) ◽

pp. 4324 ◽

Cited By ~ 9

Author(s):

Nurul Talib ◽

Faridah Salam ◽

Yusran Sulaiman

Keyword(s):

Graphene Oxide ◽

Limit Of Detection ◽

Food Product ◽

Electrochemical Immunosensor ◽

Growth Promoter ◽

Carbon Electrode ◽

Electrochemical Assay ◽

Sensor Platform ◽

Screen Printed Carbon Electrode ◽

Screen Printed

Clenbuterol (CLB) is an antibiotic and illegal growth promoter drug that has a long half-life and easily remains as residue and contaminates the animal-based food product that leads to various health problems. In this work, electrochemical immunosensor based on poly(3,4-ethylenedioxythiophene)/graphene oxide (PEDOT/GO) modified screen-printed carbon electrode (SPCE) for CLB detection was developed for antibiotic monitoring in a food product. The modification of SPCE with PEDOT/GO as a sensor platform was performed through electropolymerization, while the electrochemical assay was accomplished while using direct competitive format in which the free CLB and clenbuterol-horseradish peroxidase (CLB-HRP) in the solution will compete to form binding with the polyclonal anti-clenbuterol antibody (Ab) immobilized onto the modified electrode surface. A linear standard CLB calibration curve with R2 = 0.9619 and low limit of detection (0.196 ng mL−1) was reported. Analysis of milk samples indicated that this immunosensor was able to detect CLB in real samples and the results that were obtained were comparable with enzyme-linked immunosorbent assays (ELISA).

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First Electrochemical Sensor (Screen-Printed Carbon Electrode Modified with Carboxyl Functionalized Multiwalled Carbon Nanotubes) for Ultratrace Determination of Diclofenac

Materials ◽

10.3390/ma13030781 ◽

2020 ◽

Vol 13 (3) ◽

pp. 781 ◽

Cited By ~ 4

Author(s):

Agnieszka Sasal ◽

Katarzyna Tyszczuk-Rotko ◽

Magdalena Wójciak ◽

Ireneusz Sowa

Keyword(s):

Carbon Nanotubes ◽

Electrochemical Sensor ◽

Multiwalled Carbon Nanotubes ◽

Active Surface Area ◽

Carbon Electrode ◽

Multiwalled Carbon ◽

Screen Printed Carbon Electrode ◽

Functionalized Multiwalled Carbon Nanotubes ◽

Screen Printed

A simple, sensitive and time-saving differential-pulse adsorptive stripping voltammetric (DPAdSV) procedure using a screen-printed carbon electrode modified with carboxyl functionalized multiwalled carbon nanotubes (SPCE/MWCNTs-COOH) for the determination of diclofenac (DF) is presented. The sensor was characterized using optical profilometry, SEM, and cyclic voltammetry (CV). The use of carboxyl functionalized MWCNTs as a SPCE modifier improved the electron transfer process and the active surface area of sensor. Under optimum conditions, very sensitive results were obtained with a linear range of 0.1–10.0 nmol L−1 and a limit of detection value of 0.028 nmol L−1. The SPCE/MWCNTs-COOH also exhibited satisfactory repeatability, reproducibility, and selectivity towards potential interferences. Moreover, for the first time, the electrochemical sensor allows determining the real concentrations of DF in environmental water samples without sample pretreatment steps.

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Sensitive Electrochemical Detection of Caffeic Acid in Wine Based on Fluorine-Doped Graphene Oxide

Sensors ◽

10.3390/s19071604 ◽

2019 ◽

Vol 19 (7) ◽

pp. 1604 ◽

Cited By ~ 13

Author(s):

Venkatesh Manikandan ◽

Boopathi Sidhureddy ◽

Antony Thiruppathi ◽

Aicheng Chen

Keyword(s):

Graphene Oxide ◽

Electrochemical Sensor ◽

Caffeic Acid ◽

Photoelectron Spectroscopy ◽

Limit Of Detection ◽

Active Surface ◽

Differential Pulse ◽

Active Surface Area ◽

Food And Beverage ◽

Doped Graphene

We report here a novel electrochemical sensor developed using fluorine-doped graphene oxide (F-GO) for the detection of caffeic acid (CA). The synthesized graphene oxide (GO) and F-GO nanomaterials were systematically characterized with a scanning electron microscope (SEM), and the presence of semi-ionic bonds was confirmed in the F-GO using X-ray photoelectron spectroscopy. The electrochemical behaviours of bare glassy carbon electrode (GCE), F-GO/GCE, and GO/GCE toward the oxidation of CA were studied using cyclic voltammetry (CV), and the results obtained from the CV investigation revealed that F-GO/GCE exhibited the highest electrochemically active surface area and electrocatalytic activity in contrast to the other electrodes. Differential pulse voltammetry (DPV) was employed for the analytical quantitation of CA, and the F-GO/GCE produced a stable oxidation signal over the selected CA concentration range (0.5 to 100.0 μM) with a low limit of detection of 0.018 μM. Furthermore, the acquired results from the selectivity studies revealed a strong anti-interference capability of the F-GO/GCE in the presence of other hydroxycinnamic acids and ascorbic acid. Moreover, the F-GO/GCE offered a good sensitivity, long-term stability, and an excellent reproducibility. The practical application of the electrochemical F-GO sensor was verified using various brands of commercially available wine. The developed electrochemical sensor successfully displayed its ability to directly detect CA in wine samples without pretreatment, making it a promising candidate for food and beverage quality control.

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Voltammetric Determination of Amoxicillin Using a Reduced Graphite Oxide Nanosheet Electrode

Journal of Analytical Methods in Chemistry ◽

10.1155/2021/8823452 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Thi Hai Yen Pham ◽

Thi Trang Mai ◽

Hoang Anh Nguyen ◽

Thi Thu Hien Chu ◽

Thi Thu Ha Vu ◽

...

Keyword(s):

Graphite Oxide ◽

Graphite Electrode ◽

Limit Of Detection ◽

Reduction Process ◽

Stripping Voltammetry ◽

Active Surface ◽

Active Surface Area ◽

Accumulation Time ◽

Reduced Graphite Oxide

A reduced graphite oxide nanosheet electrode (RGOnS) was prepared as a sensor for amoxicillin (AMX) detection, an antibiotic commonly used in the livestock farm, by the square-wave adsorptive stripping voltammetry technique. Graphite oxide with nanosheet shape was produced from a graphite electrode by a chronoamperometry process at 5 V and then an electrochemical reduction process was carried out to form RGOnS with restored long-range conjugated networks and better conductivity. The electrodes were characterized by SEM, EDX, and FTIR spectroscopy. The RGOnS electrode prepared at an optimal reduction potential of −1 V for 120 s exhibits a larger electrochemical active surface area, and the obtained oxidation signal of AMX is approximately ten times higher than that of the pristine graphite electrode. The analytical conditions such as the pH of electrolyte and accumulation time were optimized. The calibration curve built under the optimal conditions provided a good linear relationship in the range of AMX concentration from 0.5–80 µM with the correlation coefficient of 0.9992. The limit of detection was calculated as 0.193 µM. Satisfactory results are obtained from the detection of the AMX in different samples using the prepared electrode.

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Simultaneous Determination of Four DNA bases at Graphene Oxide/Multi-Walled Carbon Nanotube Nanocomposite-Modified Electrode

Micromachines ◽

10.3390/mi11030294 ◽

2020 ◽

Vol 11 (3) ◽

pp. 294 ◽

Cited By ~ 1

Author(s):

Shuting Wang ◽

Celia Ferrag ◽

Meissam Noroozifar ◽

Kagan Kerman

Keyword(s):

Graphene Oxide ◽

Carbon Nanotube ◽

Modified Electrode ◽

Rate Constant ◽

Artificial Saliva ◽

Simultaneous Detection ◽

Internal Standard ◽

Active Surface ◽

Active Surface Area ◽

Multi Walled Carbon Nanotube

In this study, we developed a modified glassy carbon electrode (GCE) with graphene oxide, multi-walled carbon nanotube hybrid nanocomposite in chitosan (GCE/GO-MWCNT-CHT) to achieve simultaneous detection of four nucleobases (i.e., guanine (G), adenine (A), thymine (T) and cytosine (C)) along with uric acid (UA) as an internal standard. The nanocomposite was characterized using TEM and FT-IR. The linearity ranges were up to 151.0, 78.0, 79.5, 227.5, and 162.5 µM with a detection limit of 0.15, 0.12, 0.44, 4.02, 4.0, and 3.30 µM for UA, G, A, T, and C, respectively. Compared to a bare GCE, the nanocomposite-modified GCE demonstrated a large enhancement (~36.6%) of the electrochemical active surface area. Through chronoamperometric studies, the diffusion coefficients (D), standard catalytic rate constant (Ks), and heterogenous rate constant (Kh) were calculated for the analytes. Moreover, the nanocomposite-modified electrode was used for simultaneous detection in human serum, human saliva, and artificial saliva samples with recovery values ranging from 95% to 105%.

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An Electrocatalytic Screen-Printed Amperometric Sensor for the Selective Measurement of Thiamine (Vitamin B1) in Food Supplements

Biosensors ◽

10.3390/bios9030098 ◽

2019 ◽

Vol 9 (3) ◽

pp. 98 ◽

Cited By ~ 2

Author(s):

Amy Smart ◽

Kelly L. Westmacott ◽

Adrian Crew ◽

Olena Doran ◽

John P. Hart

Keyword(s):

Limit Of Detection ◽

Vitamin B1 ◽

Underlying Mechanism ◽

Food Supplements ◽

Screen Printed Carbon Electrode ◽

Thiolate Anion ◽

Analytical Response ◽

Operating Potential ◽

Response Current ◽

Screen Printed

An electrocatalytic screen-printed sensor has been investigated for the measurement of the biologically important biomolecule vitamin B1 (thiamine) for the first time in food supplements. Under basic conditions, the vitamin was converted to its electrochemically active thiolate anion species. It was shown that an electrocatalytic oxidation reaction occurred with the screen-printed carbon electrode containing the mediator cobalt phthalocyanine (CoPC-SPCE). This had the advantage of producing an analytical response current at an operating potential of 0 V vs. Ag/AgCl compared to +0.34 V obtained with plain SPCEs. This resulted in improved selectivity and limit of detection. Detailed studies on the underlying mechanism occurring with the sensor are reported in this paper. A linear response was obtained between 0.1 and 20 µg mL−1, which was suitable for the quantification of the vitamin in two commercial products containing vitamin B1. The mean recovery for a multivitamin tablet with a declared content of 5 mg was 101% (coefficient of variation (CV) of 9.6%). A multivitamin drink, which had a much lower concentration of vitamin B1 (0.22 mg/100 mL), gave a mean recovery of 93.3% (CV 7.2%). These results indicate that our sensor holds promise for quality control of food supplements and other food types.

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Uric Acid Biosensor Based on Biofilm of L. plantarum using Screen-Printed Carbon Electrode Modified by Magnetite

Al-Kimia ◽

10.24252/al-kimia.v6i2.6300 ◽

2018 ◽

Vol 6 (2) ◽

Author(s):

Dian Siska Rahma Fatonah ◽

Deden Saprudin ◽

Dyah Iswantini ◽

Novik Nurhidayat

Keyword(s):

Uric Acid ◽

Limit Of Detection ◽

Clinical Analysis ◽

Carbon Electrode ◽

Range Limit ◽

Good Electrocatalytic Activity ◽

Screen Printed Carbon Electrode ◽

Limit Of Quantitation ◽

The Stability ◽

Screen Printed

Biosensor based on biofilm of L. plantarum has been successfully done for determination of uric acid in human urine compared with colorimetric enzymatic produced relative error of less than 5%. L. plantarum has uricase activity to react with uric acid, to maintain the stability of bacteria forming themselves into biofilms. Magnetite is known to increase sensitivity of the biosensor. The combination of magnetite-polyethylene glycol (Fe3O4-PEG) was used to modify the surface of Screen-Printed Carbon Electrode modified (SPCE) and the resulting modified electrode (biofilm/Fe3O4/PEG/SPCE) displayed good electrocatalytic activity to the oxidation of UA. The composition of biofilms with optical density 1, magnetite 100 mgmL-1 and PEG 3% v / v were able to increase the current up to 48% in 4mM of UA. The biosensor with an optimum composition produced good linearity with a concentration range, limit of detection, limit of quantitation, sensitivity, and repeatability were found to be 0.1 - 4.3 mM, 70 µM, 234 µM, 25.392 µA mM-1, 2.38%, respectively. This biosensor stable up to 49 days of measurement with the remaining activity was 90.70% and selective for interference compounds such as salt, urea, glucose, ascorbic acid. This method has a good stability, sensitivity, and potential application in clinical analysis. Keyword: biofilm, biosensor, L. plantarum, magnetite, uric acid.

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Poly(1,5-Diaminonaphthalene)-Modified Screen-Printed Device for Electrochemical Lead Ion Sensing

Advances in Polymer Technology ◽

10.1155/2021/6637316 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Mai T. T. Nguyen ◽

Huy L. Nguyen ◽

Dung T. Nguyen

Keyword(s):

Surface Defects ◽

Limit Of Detection ◽

Tap Water ◽

Anodic Stripping Voltammetry ◽

Modified Electrodes ◽

Stripping Voltammetry ◽

Electrochemical Determination ◽

Lead Ion ◽

Ion Sensing ◽

Screen Printed

Poly(1,5-diaminonaphthalene) has been electropolymerized on the screen-printed device with a three-electrode configuration. The modified electrodes have been developed as the new electrode for electrochemical determination of trace levels of lead ions (Pb2+). The poly(1,5-diaminonaphthalene) film prevents the deposition of Pb2+ into the surface defects of the bare carbon screen-printed electrode and possesses sensitivity to heavy metal ions thanks to amine and secondary amino groups on the polymer chain. The square wave anodic stripping voltammetry was applied to detect Pb2+ ions, showing a sharp stripping peak with the linear range from 0.5 μg·L-1 to 5.0 μg·L-1 ( R 2 = 0.9929 ). The limit of detection was found to be 0.30 μg·L-1. The sensors were applied to the analysis of Pb2+ in the tap water sample matrix with satisfactory results.

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