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Analytical & Bioanalytical Electrochemistry - Volume:11 Issue: 3, Mar 2019

Analytical & Bioanalytical Electrochemistry
Volume:11 Issue: 3, Mar 2019

  • تاریخ انتشار: 1398/01/27
  • تعداد عناوین: 10
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  • Nataliya Malakhova *, Anton Tsmokalyuk, Alexandra Ivoilova, ndrey Tumashov, Vladimir Rusinov, Alla Ivanova, Alisa Kozitsina Pages 292-303
    Bare carbon screen-printed electrode based on carbon ink Electrodag 407C was used for quantitation of the new Russian anti-influenza drug Triazavirin. For the first time it was established that an electrochemical activity of an active substance of the drug (sodium salt of 2-methylthio-6-nitro-1,2,4-triazolo[5,1-c][1,2,4]triazin-7-one, dihydrate, triazavirin) is caused by electrochemical reduction of a nitro group bonded to a conjugated aromatic system. The effect of voltammetric mode, pH of electrolyte, scan rate, time and potential of preliminary accumulation on the current of triazavirin reduction were studied. A quick, simple and “green” method for triazavirin determination using a direct square wave cathodic voltammetry was developed. The peak current obtained was linearly related to triazavirin concentration in the range of 0.1 to 180 mg L-1 with correlation coefficient of 0.9996. Good analytical performance was achieved with a detection limit of 0.04 mg L-1, a repeatability of 1.0% and an intermediate precision ˂2%. The developed method was validated and applied for the analysis of Triazavirin capsules. Found values are close to the claimed content and are in good agreement with the results of the HPLC method.
    Keywords: Triazavirin, Bare carbon screen-printed electrode, Square wave voltammetry, Validation
  • Nidhal Sahib Mansoor, Arash Fattah, alhosseini *, Arash Shishehian, Hassan Elmkhah Pages 304-320
    In this paper, corrosion behavior of single and multilayer (TiN, CrN and TiN/CrN) deposited coatings on Ni-Cr dental alloy in artificial saliva using cathodic arc evaporation-physical vapor deposition (CAE-PVD) technique were investigated. The corrosion behavior of uncoated and coated Ni-Cr prosthetic dental alloy has been investigated electrochemically in addition to the other way represented by the quantity measurement of corrosion products which is resulted from the Ni-Cr dental alloys. Fusayama artificial saliva has been utilized as media for measuring all electrochemical behaviors. The surfaces of samples have been analyzed using X-ray diffraction (XRD), energy dispersion spectroscopy (EDS), and scanning electron microscopy (SEM). The results indicated that the coating procedure that has applied to Ni-Cr dental alloy may change wettability by decreasing the hydrophilicity of the surface. The results indicated that the strongest hydrophobic character is exhibited by CrN coating. Potentiodynamic polarization and Nyquist plots showed that CrN coating had an exceptionally high polarization resistance compared to Ni-Cr dental alloy, TiN and TiN/CrN coatings.
    Keywords: Dental alloy, Physical vapor deposition, Corrosion behavior, Artificial saliva
  • Suresh M. Tuwar *, Rohini M. Hanabaratti, Jayant I. Gowda Pages 321-332
    Electrochemical investigations of 4-aminoantipyrine (4-AA) at polyglycine modified glassy carbon electrode (poly(glycine)MGCE) was carried out in acidic phosphate buffer medium. 4-AA exhibited a well-defined oxidation peak at a potential of 0.446 V with an oxidation current of 5.72 μA. Compared to the oxidation currents obtained by bare glassy carbon electrode (GCE) and modified electrode, poly(glycine)MGCE exhibited good catalytic activity towards the determination of 4-AA. Results of scan rate investigation indicate that electrode process was diffusion controlled. Effect of concentration of the analyte on current was studied. With the help of calibration curve, detection limit was calculated and was found to be 0.97 nM. Prepared electrode was applied for the recovery study of drug in urine with spiked as well as real samples.
    Keywords: Poly(glycine) modification, Diffusion controlled, Calibration curve, Urine samples, Detection limit
  • Mohammed Barbouchi *, Bouchra Benzidia, Mostafa El Idrissi, M’barek Choukrad Pages 333-348
    The essential oils of aromatic and medicinal plants are ones of the green corrosion inhibitors they are most valuable environmentally friendly, biodegradable in nature and are synthesis by simple procedure with a low cost. This paper concentrates on the corrosion inhibitory properties of the essential oils: Effect on iron corrosion in neutral chloride media (3% NaCl solution). The essential oils was obtained from twigs, leaves and fruits of Pistacia lentiscus L. (PL), collected in two different regions (Melloussa (MS) and Moulay Idriss Zerhoun (MIZ)) of Morocco. The PL essential oils effect against the corrosion of iron in 3% NaCl solution was carried out using the weight loss, as well as electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) curves. Among tested essential oils, the best inhibitive effect was obtained for essential oil of PL twigs from MIZ. Indeed, the optimum inhibition efficiency 81.45% was achieved in the presence of 3000 ppm inhibitor. The results obtained from different techniques used in this research are in very good agreement and revealed that PL essential oils could serve as a source of green corrosion inhibitors on iron in 3% NaCl solution.
    Keywords: Essential oils, Pistacia lentiscus L., Green corrosion inhibitor, Iron, 3% NaCl
  • Taher Alizadeh *, Sahar Nayeri Pages 349-361
    In this work, a new method was introduced for citric acid determination in real samples. The method is based on a carbon paste electrode, impregnated with magnetite nanoparticles (Fe2O3). The electrocatalytic activity of magnetite nanoparticles-modified carbon paste electrode (Fe2O3-CPE) was substantiated utilizing cyclic voltammetry (CV). Performing of CV in different pH values as well as various scan rates resulted in some evidences on the citric acid electroxidation mechanism. Electrochemical impedance spectroscopy gave obvious indication for the enhancement of charge transfer rate by the magnetite nanoparticles. Various parameters, affecting the electrode performance were studied and optimized. Square wave voltammetry (SWV) method was found to be an appropriate analytical technique to obtain enhanced electroxidation signal and thus it was adopted as the signal recording method. Using SWV and Fe2O3-CPE, a linear dynamic range of 2.5×10-5-1×10-3 mol L-1 as well as detection limit of 1 μmolL-1 was obtained for citric acid determination. Relative standard deviation percent of three repeated determinations was found to be about 4.1%. The developed method was utilized for citric acid amount estimation in different commercial fruit juices samples which led to satisfactory results.
    Keywords: Magnetite nanoparticles, Square wave voltammetry, Carbon paste, Fruit juice
  • Mustafa Aghazadeh* Pages 362-372
    In this paper, with manganese doping into the crystal structure of iron oxide and then surface coating with dextran/PEI layers, two novel types of superparamagnetic particles are fabricated. A simple one-step cathodic electrochemical synthesis is developed for preparation of these magnetic nanoparticles. The deposition and surface coating are simultaneously performed from the dextran or PEI added aqueous solution of 0.1M Fe(II) chloride, 0.2M Fe(III) nitrate and 0.05M manganese nitrate. FT-IR, EDAX and FE-SEM analyses showed nano-size of the prepared iron oxide particles and the polymer layers onto their surface. Negligible remanence and coercivity values exhibited by the prepared iron oxide particles verified their excellent superparamagnetic behavior. Based on the analyses results, it was proven that the prepared magnetic particles are good candidates for biomedical applications.
    Keywords: Iron oxide, Dextran, PEI, Magnetic powder, Electrochemical synthesis
  • El Hassan El Assiri *, Majid Driouch, Zakariae Bensouda, Mustapha Beniken, Ali Elhaloui, Mouhcine Sfaira, Taoufiq Saffaj Pages 373-395
    The Density Functional Theory (DFT) study was used to investigate the corrosion inhibition performance of four inhibitors namely: 2,3-dihydro-1H-pyrrolo [2,1c][1,4] benzodiazepine-5,11(10H,11aH)-dione (BZD1); 2,3-dihydro-1H-pyrrolo [2,1c][1,4] benzodiazepine-5,11(10H,11aH)-dithione (BZD2); 10-benzyl-pyrrolo [2,1-c][1,4] benzodiazepine-5,11-dione (BZD=2O) and 10-benzyl-pyrrolo [2,1-c][1,4] benzodiazepine-5,11-dithione (BZD=2S) on carbon steel using the B3LYP/6-311G(d, p) level of theory. The geometry optimization was conducted only on the neutral form of all benzodiazepine derivatives, without any protonated form as testified by the Marvin software. The most relevant quantum chemical parameters according to their potential action as corrosion inhibitors were calculated. The descriptors considered were: the EHOMO (highest occupied molecular orbital energy), the ELUMO (lowest unoccupied molecular orbital energy), the energy gap (ΔE), the dipole moment (μ), the hardness (η), the softness (σ), the absolute electronegativity (χ), the total energy (Etot), the ionization potential (IP), the electron affinity (EA) and the fraction of electrons transferred (ΔN). Besides, the local reactivity was analyzed through the Fukui function in order to compare the possible sites for nucleophilic and electrophilic attacks. The electronic properties of these inhibitors obtained by DFT were correlated with their experimental efficiencies using two mathematical models, based-QSPR approaches; the multiple linear regressions (MLR) and the multiple polynomial regressions (MPR). The quantum chemical study showed that the theoretical and experimental results were in good agreement, and the statistical results revealed that the MPR was the most relevant and predictive model in comparison with the MLR model, with a very high determination coefficient (R2 = 0.99), adjusted determination coefficient (R2adj = 0.99) and predicted determination coefficient (R2pred = 0.97)
    Keywords: Corrosion inhibition, Benzodiazepine, C-steel, DFT at B3LYP-6-31G**, QSPR
  • Dyamanna Thippeswamy, Yanjerappa Arthoba Nayaka*, Matad Mallikarjunaiah Vinay Pages 396-406
    The electrodeposit of Zn-Mn-V2O5 alloy composite coating has been obtained on the surface of steel using acid sulphate bath. The bath composition and operating variables such as pH, current density and temperature were optimized through Hull-cell experiments. The corrosion properties of Zn, Zn-Mn and Zn-Mn-V2O5 have been studied in 3.5% wt. NaCl using potentiodyanamic polarization measurements like Tafel extrapolation and which showed the corrosion rates (CR) of 7.234×10-5 g h-1, 5.392×10-5 g h-1, and 2.909×10-6 g h-1, respectively. The polarization resistance (RP) values of 938.9 Ω cm2, 3403.8 Ω cm2 and 4287.5 Ω cm2 by electrochemical impedance spectroscopy (EIS) also confirm the better corrosion resistance of Zn-Mn-V2O5 compare to Zn, Zn-Mn alloy coatings. The current efficiency and throwing power of the optimized bath solution were measured. The surface morphology of Zn-Mn-V2O5 composite coating has been analyzed by SEM. The X-ray diffraction analysis (XRD) was employed to study the average crystallite size of the composite coatings.
    Keywords: Corrosion, EDX, EIS, Tafel, Zn- composite coating
  • Isa Karimzadeh* Pages 407-415
    In this research, Co-doped Fe3O4/NH2-graphene nanocomposite is produced by direct current electrodesotion technique from an aqueous electrolyte containing the iron/cobalt chloride/nitrate salts and amine-functionalized porous graphene. The applied electrochemical parameters were i=5 mA/cm2, Tbath=25oC and tdeposition= 15 min. The electrochemical growth of magnetic particles onto graphene layers and formation of Co-IONPs/f-PG composite were tuned through XRD, FT-IR, FE-SEM, VSM and EDAX analyses. The magnetite phase and particle morphology of the deposited iron oxide onto graphene layers was indicated by XRD pattern and FE-SEM images. The cobalt content of deposited iron oxide was clearly revealed in the EDAX data. The magnetic measurement by vibrating sample magnetometer (VSM) technique exhibited superparamagnetic nature with saturation magnetization and retentivity values of 47.65 emu g–1 and 2.26 emu g–1 for the electro-synthesized magnetic nanocomposite. In final, direct cathodic electrodeposited is proposed as simple procedure for production of iron oxides with various graphene-based materials.
    Keywords: Nanocomposite, Iron oxide, cobalt doping, Functionalized graphene, Electrochemical synthesis
  • Saeed Kakaei* Pages 416-426
    In this paper, two-types of superparamagnetic metal-ions doped iron oxide nanoparticles including ethylenediaminetetraacetic acid-grafted Zn2+ doped SPIONs (EDTA-Zn-SPIONs) and polyvinyl chloride-grafted Zn2+ doped SPIONs (PVC-Zn-SPIONs) nanoparticles are reported. These nanoparticles are fabricated through base generation cathodic electrodeposition method. The surface coat onto the prepared particles and zinc-doping into iron oxide were proved though Fourier-transform infrared spectroscopy, Field-emission scanning electron microscopy and Energy Dispersive X-ray analyses. The magnetic data was provided by sample vibrating magnetometer (VSM) technique. The EDTA-Zn-SPIONs exhibited magnetic performances of Ms=34.12 emu/g, Hci= 9.1G, Mr=0.29 emu/g, Mr(+)=+0.21 emu/g, Mr(-)=-0.38 emu/g Hci(+)=11.28G and Hci(-)=-6.75 G. Also, PVC-Zn-SPIONs showed Ms=28.45 emu/g, Hci=5.75G, Mr=0.14 emu/g, Mr(+)=-0.11 emu/g, Mr(-)=-0.18 emu/g, Hci(+)=7.75G and Hci(-)=3.75G. These data confirmed the quality of both prepared particles for biomedical applications.
    Keywords: Nanoparticles, Electrochemical synthesis, Iron oxide, Doping, Surface grafting