scholarly journals Modification of screen printed gold electrode with 1,4-dithiothreitol: Application to sensitive voltammetric determination of Sudan II

Author(s):  
Kuddusi Karaboduk

Abstract Objectives The aim of this study is to investigate the electrochemical behavior of Sudan II (SuII) using a screen printed gold electrode (SPGE) modified with 1,4-dithiothreitol (DTT) and to determine the amount of Sudan II by voltammetry. Materials and Methods A DTT modified screen printed gold electrode (DTT/SPGE) was fabricated and its application for differential pulse voltammetric (DPV) determination of SuII was reported. Fourier transform infrared spectroscopy (FT-IR), cyclic voltammetry (CV) and electrochemical impedance spectroscopy were used for the characterization of modified electrode. The effects of instrumental and chemical parameters were optimized for the determination of SuII. The fabricated electrode was used for the analysis of SuII in fortified and real samples. High performance liquid chromatography (HPLC) was preferred as a reference method for the evaluation of the obtained voltammetric results. Results The electrochemical studies and FT-IR demonstrated that the SPGE was modified with DTT. The obtained peak current at DTT/SPGE was 6.67 times higher than that recorded with SPGE. At the optimized conditions of DPV in pH = 2.5 of H2SO4, the oxidation peak current of SuII was proportional to its concentration in range: 0.001 - 1.500 μmol L -1 with a detection limit of 0.0002 μmol L -1 (S/N=3). For the analysis of SuII, 101.67 - 104.33% of recovery percentage was obtained. Conclusions A new electrode was successfully improved for the determination of SuII. This highly selective and sensitive electrode supplied the fast determination of SuII in ketchup, chili sauce and salsa dip sauce. In addition, voltammetric and chromatographic results are found to be consistent.

Author(s):  
Mohammad Mehmandoust ◽  
Amirhossein Mehmandoust ◽  
Nevin Erk

A selective and facile voltammetric method based on titanium dioxide nanoparticles and Nafion (Nafion/TiO2 NPs) on the screen-printed electrode (SPE) was proposed for olopatadine determination. Followed by the synthesis of TiO2 nanoparticles, various methods, including high-resolution transmission electron microscopy (HR-TEM), ultraviolet-visible spectroscopy (UV-Vis), energy-dispersive X-ray (EDX) Raman spectrum, and electrochemical impedance spectroscopy (EIS) were utilized to characterize the nanomaterials. Nafion/TiO2 on the screen-printed electrode (NFN/TiO2/SPE) was used to determine olopatadine in concentration ranges of 0.01 to 0.07 and 0.07 to 14.6 µM with a limit of quantification as low as 7.0 nM, via differential pulse voltammetry technique. The NFN/TiO2/SPE offered a high-performance ability to determine olopatadine in the eye drop sample with satisfactory recovery data of 98.2–99.0 %. Also, the developed electrode showed good reproducibility, repeatability, and high selectivity features. The obtained results indicate that NFN/TiO2/SPE could be utilized as an appropriate candidate for electrochemical olopatadine sensing.


2019 ◽  
Vol 97 (2) ◽  
pp. 140-146
Author(s):  
Tian Gan ◽  
Zhikai Wang ◽  
Mengru Chen ◽  
Wanqiu Fu ◽  
Haibo Wang ◽  
...  

In this work, the Ag@Cu particles with yolk–shell nanostructure was prepared by facile solvothermal method, which was modified on glassy carbon electrode (GCE) to fabricate electrochemical sensor for the convenient and fast determination of p-aminobenzoic acid (PABA). The surface morphology and electrochemical properties of the as-prepared Ag@Cu nanocomposite modified electrode were characterized by scanning electron microscopy, transmission electron microscopy, chronocoulometry, and electrochemical impedance spectroscopy. Further, the electrochemical sensing of PABA was performed on the Ag@Cu/GCE using cyclic voltammetry and differential pulse voltammetry techniques, showing high catalytic activity. Under the optimal conditions, the sensor exhibited a wide linear range, high sensitivity, and low detection limit of 0.315 μmol/L for PABA. The developed sensor was also successfully applied for PABA detection in anesthetic and cosmetics with satisfactory results.


Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3581
Author(s):  
Jędrzej Kozak ◽  
Katarzyna Tyszczuk-Rotko ◽  
Magdalena Wójciak ◽  
Ireneusz Sowa

In this work, an electrochemically activated screen-printed carbon electrode modified with sodium dodecyl sulfate (aSPCE/SDS) was proposed for the simultaneous determination of paracetamol (PA), diclofenac (DF), and tramadol (TR). Changes of surface morphology and electrochemical behaviour of the electrode after the electrochemical activation with H2O2 and SDS surface modification were studied by scanning electron microscopy (SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The influence of various parameters on the responses of the aSPCE/SDS such as pH and concentration of the buffer, SDS concentration, and techniques parameters were investigated. Using optimised conditions (Eacc. of −0.4 V, tacc. of 120 s, ΔEA of 150 mV, ν of 250 mV s−1, and tm of 10 ms), the aSPCE/SDS showed a good linear response in the concentration ranges of 5.0 × 10−8–2.0 × 10−5 for PA, 1.0 × 10−9–2.0 × 10−7 for DF, and 1.0 × 10−8–2.0 × 10−7 and 2.0 × 10−7–2.0 × 10−6 mol L−1 for TR. The limits of detection obtained during the simultaneous determination of PA, DF, and TR are 1.49 × 10−8 mol L−1, 2.10 × 10−10 mol L−1, and 1.71 × 10−9 mol L−1, respectively. The selectivity of the aSPCE/SDS was evaluated by examination of the impact of some inorganic and organic substances that are commonly present in environmental and biological samples on the responses of PA, DF, and TR. Finally, the differential pulse adsorptive stripping voltammetric (DPAdSV) procedure using the aSPCE/SDS was successfully applied for the determination of PA, DF, and TR in river water and serum samples as well as pharmaceuticals.


2013 ◽  
Vol 78 (9) ◽  
pp. 1373-1385 ◽  
Author(s):  
Marina Nevescanin ◽  
Milka Avramov-Ivic ◽  
Slobodan Petrovic ◽  
Dusan Mijin ◽  
Sonja Banovic-Stevic ◽  
...  

The catalytic abilities of gold electrode were tested for the quantitative determination of amphetamine (A) and 3,4-methylenedioxy-N-methylamphetamine (MDMA) standards by their oxidation using cyclic voltammetry (CV). The value of the oxidative currents of A and MDMA standards at 0.80 V vs. SCE in 0.05 M NaHCO3 at the scan rate of 50 mV/s is linear function of concentration in range of 110.9-258.9 mM and 38.7-229.2 mM, respectively. Square wave voltammetry (SWV) revealed linear increase of current with concentration of MDMA (range 30.9-91.6 mM) and thus quantitative determination of amphetamine derivates. SWV analysis is successfully performed in spiked urine samples as well. A and MDMA in the presence of sucrose and as a content in illegally produced tablets were also analyzed. The voltammetric determination of A and MDMA derivatives using CV and SWV at gold electrode is a rapid, selective and simple procedure and its accuracy was confirmed with reference method, high performance liquid chromatography (HPLC). The spiked urine samples analysis offers additional possibility for the rapid detection of A and MDMA in human urine.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Syeda Aqsa Batool Bukhari ◽  
Habib Nasir ◽  
Lujun Pan ◽  
Mehroz Tasawar ◽  
Manzar Sohail ◽  
...  

AbstractNon-enzymatic electrochemical detection of catechol (CC) and hydroquinone (HQ), the xenobiotic pollutants, was carried out at the surface of novel carbon nanocoils/zinc-tetraphenylporphyrin (CNCs/Zn-TPP) nanocomposite supported on glassy carbon electrode. The synergistic effect of chemoresponsive activity of Zn-TPP and a large surface area and electron transfer ability of CNCs lead to efficient detection of CC and HQ. The nanocomposite was characterized by using FT-IR, UV/vis. spectrophotometer, SEM and energy dispersive X-ray spectroscopy (EDS). Cyclic voltammetry, differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy were used for the electrochemical studies. CNCs/Zn-TPP/GCE nanosensor displayed a limit of detection (LOD), limit of quantification (LOQ) and sensitivity for catechol as 0.9 µM, 3.1 µM and 0.48 µA µM−1 cm−2, respectively in a concentration range of 25–1500 µM. Similarly, a linear trend in the concentration of hydroquinone detection was observed between 25 and 1500 µM with an LOD, LOQ and sensitivity of 1.5 µM, 5.1 µM and 0.35 µA µM−1 cm−2, respectively. DPV of binary mixture pictured well resolved peaks with anodic peak potential difference, ∆Epa(CC-HQ), of 110 mV showing efficient sensing of CC and HQ. The developed nanosensor exhibits stability for up to 30 days, better selectivity and good repeatability for eight measurements (4.5% for CC and 5.4% for HQ).


Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 3926 ◽  
Author(s):  
Umi Mohd Azmi ◽  
Nor Yusof ◽  
Norzila Kusnin ◽  
Jaafar Abdullah ◽  
Siti Suraiya ◽  
...  

A rapid and sensitive sandwich electrochemical immunosensor was developed based on the fabrication of the graphene/polyaniline (GP/PANI) nanocomposite onto screen-printed gold electrode (SPGE) for detection of tuberculosis biomarker 10-kDa culture filtrate protein (CFP10). The prepared GP/PANI nanocomposite was characterized using Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM). The chemical bonding and morphology of GP/PANI-modified SPGE were studied by Raman spectroscopy and FESEM coupled with energy dispersive X-ray spectroscopy, respectively. From both studies, it clearly showed that GP/PANI was successfully coated onto SPGE through drop cast technique. Cyclic voltammetry was used to study the electrochemical properties of the modified electrode. The effective surface area for GP/PANI-modified SPGE was enhanced about five times compared with bare SPGE. Differential pulse voltammetry was used to detect the CFP10 antigen. The GP/PANI-modified SPGE that was fortified with sandwich type immunosensor exhibited a wide linear range (20–100 ng/mL) with a low detection limit of 15 ng/mL. This proposed electrochemical immunosensor is sensitive, low sample volume, rapid and disposable, which is suitable for tuberculosis detection in real samples.


2019 ◽  
Vol 63 (1) ◽  
Author(s):  
Mehdi Jalali ◽  
Zeinab Deris Falahieh ◽  
Mohammad Alimoradi ◽  
Jalal Albadi ◽  
Ali Niazi

The electrochemical behavior of Bi+3 ions on the surface of a glassy carbon electrode, in acidic media and in the presence of tamoxifen, was investigated. Cyclic voltammetry, chronoamperometry, differential pulse voltammetry, electrochemical impedance spectroscopy, and scanning electron microscopy with energy-dispersive X-ray spectroscopy were used to find the probable mechanism contributing to the reduction of the peak height of bismuth oxidation with an increase in the concentration of tamoxifen. The obtained results show a slight interaction between the bismuth species and tamoxifen which co-deposit on the surface of glassy carbon electrode. Therefore, the reduction in the peak height of bismuth oxidation as a function of tamoxifen concentration was used to develop a new differential pulse anodic striping voltammetry method for determination of trace amount of tamoxifen. The effects of experimental parameters on the in situ DPASV of Bi+3 ions in the presence of tamoxifen shown the optimal conditions as: 2 mol L-1 H2SO4 (1% v v-1 MeOH), a deposition potential of -0.5 V, a deposition time of 60 s, and a glassy carbon electrode rotation rate of 300 rpm. The calibration curve was plotted in the range of 0.5 to 6 µg mL-1 and the limits of detection and quantitation were calculated to be 3.1 × 10-5 µg mL-1 and 1.0 × 10-4 µg mL-1, respectively. The mean, RSD, and relative bias for 0.5 µg mL-1 (n=5) were found to be 0.49 µg mL-1, 0.3%, and 2%, respectively. Finally, the proposed method was successfully used for the determination of tamoxifen in serum and pharmaceutical samples.


2019 ◽  
Vol Vol. 14, No.1 ◽  
pp. 5-14 ◽  
Author(s):  
Anastasiya Tkachenko ◽  
Mykyta Onizhuk ◽  
Oleg Tkachenko ◽  
Leliz T. Arenas ◽  
Edilson V. Benvenutt ◽  
...  

In the present study, an electrochemical sensor based on the electrode (SiMImCl/C) consisting of graphite and silica, grafted with 1-n-propyl-3-methylimidazolium chloride was used for ascorbic acid (AA) quantification in pharmaceuticals and food formulations. Cyclic voltammetry and electrochemical impedance spectroscopy were applied for electrochemical characterization of the SiMImCl/C electrode. The cyclic voltammetry study revealed that the oxidation of AA on this electrode is an irreversible process, realized by adsorption and diffusion limited step. The differential pulse voltammetry was applied to develop a procedure for the AA determination. The linear range was found to be 0.3–170 μmol L-1 and the limit of detection – 0.1 μmol L-1. The proposed SiMImCl/C electrode has long term stability and does not show electrochemical activity towards the analytes, which commonly coexist with AA. The sensor was successfully used for quantification of AA in food and pharmaceutical formulations.


2019 ◽  
Vol 9 (2) ◽  
pp. 113-123 ◽  
Author(s):  
Sayed Zia Mohammadi ◽  
Hadi Beitollahi ◽  
Tahereh Rohani ◽  
Hossein Allahabadi

Electrochemical characteristics of carvacrol were investigated on a screen-printed electrode (SPE) modified with La2O3/Co3O4 nanocomposite by using voltammetric techniques, which displayed a well-defined peak for sensitive carvacrol determination in phosphate buffer solution (PBS) at pH 7.0. La2O3/Co3O4 nanoparticles demonstrated suitable catalytic activity for carvacrol determination by differential pulse voltammetry (DPV) technique. Besides, determination of carvacrol in a real samples was recognized in the light of electrochemical findings and a validated voltammetric technique for quantitative analysis of carvacrol in a real formulation was proposed. The DPV peak currents were found to be linear in the concentration range of 10.0 to 800.0 μM. The limit of detection (LOD) was found to be 1.0 μM.


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