Matad Mallikarjunaiah Vinay; Kempugonapla Virupakshappa Basavarajappa; Puttaiah Manjunatha; Hanumasagara Thimmappa Purushothama; Rangapura Onkarappa Yathisha; Yanjerappa Arthoba Nayaka
Volume 12, Issue 2 , February 2020, , Pages 155-167
Abstract
A rapid electrochemical analysis of sulfadiazine (SFZ) has been carried out by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods by employing a sensitive single walled carbon nanotube-molybdenum disulfide nanocomposite/poly ethylene glycol modified carbon paste electrode (SWCNT-MoS2/PEG/CPE). ...
Read More
A rapid electrochemical analysis of sulfadiazine (SFZ) has been carried out by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods by employing a sensitive single walled carbon nanotube-molybdenum disulfide nanocomposite/poly ethylene glycol modified carbon paste electrode (SWCNT-MoS2/PEG/CPE). The SFZ shows anodic peak potential at 0.94 V (vs. Ag/AgCl) in 0.1 M PBS of pH 7.0. The SFZ has been examined at different scan rate from 50 to 300 mVs-1 in 0.1 M PBS of pH 7.0 and the nature of mass transfer route is diffusion-controlled process. The different pH from 5.6 to 8.0 was analyzed at SFZ and obtained the slope value 0.063 proves the equal number of electrons and protons were involved in the reaction. In DPV mode LOD of SFZ in the linear range of 2-90 μM was found to be 1.69 μM. The prepared electrode was examined by electrochemical impedance spectroscopy (EIS) using 5 mM K3[Fe(CN)6] in 0.1 M KCl. The effective surface area of SWCNT-MoS2/PEG/CPE was found to be 0.262 cm2. This method could be successfully employed to determine the concentration of SFZ in biological fluids.
Niloofar Dehdashtian; Seyed-Ahmad Shahidi; Majedeh Bijad
Volume 12, Issue 3 , March 2020, , Pages 289-300
Abstract
Fast and sensitive response electrochemical sensor based on CoFe2O4 nanoparticle and 1-buthyl-3-methyl imidazolium bromide room temperature ionic liquids carbon paste electrode (CoFe2O4/NP/ILs/CPE) is fabricated for the determination of Xanthine (Xt) in the presences of Caffeine in fish and fruit samples. ...
Read More
Fast and sensitive response electrochemical sensor based on CoFe2O4 nanoparticle and 1-buthyl-3-methyl imidazolium bromide room temperature ionic liquids carbon paste electrode (CoFe2O4/NP/ILs/CPE) is fabricated for the determination of Xanthine (Xt) in the presences of Caffeine in fish and fruit samples. In the first step, CoFe2O4/NP was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) and results showed synthesized nanoparticle with diameter between 26.92-29.22 nm. The electro-oxidation of Xt and Caffeine occurred at a potential about 0.7 V and 1.1 V, which was much better in comparison with bare carbon paste electrode in phosphate buffer (pH=6.0) at the surface of the (CoFe2O4/NP/ILs/CPE). Other electrochemical techniques were also investigated including cyclic voltammetry, differential pulse voltammetry (DPV) and chronoamperometry at CoFe2O4/NP/ILs/CPE. At optimized conditions for Xt and Caffeine analysis, DPV peak currents showed a wide linear dynamic ranging from 8.0 nM to 500 μM and detection limit for Xt was 3.0 nM and of course we obtained good dynamic range between 0.1 to 300 μM and good limit of detection 0.05 μM for caffeine. As a result, the proposed electrode could determine Xt in the presences of Caffeine in real samples with good selectivity and high sensitivity.
Muna Shueai Yahya; Ghizlan Kaichouh; Mariam Khachani; Miloud El Karbane; Mohammed Azeem Arshad; Abdelkader Zarrouk; Kacem El Kacemi
Volume 12, Issue 4 , April 2020, , Pages 425-436
Abstract
The aim of this work is to study the degradation and mineralization of antibiotic ofloxacin in aqueous medium using the Electro-Fenton method as advanced oxidation technology. In this context, Pt/carbon-felt cell was used to investigate the influence of various parameters including initial pH, different ...
Read More
The aim of this work is to study the degradation and mineralization of antibiotic ofloxacin in aqueous medium using the Electro-Fenton method as advanced oxidation technology. In this context, Pt/carbon-felt cell was used to investigate the influence of various parameters including initial pH, different supporting electrolytes, different metal ions as a catalyst and antibiotic concentration over the mineralization rate and instantaneous current efficiency. The chemical oxygen demand (COD) measurements during the electrolysis allowed the evaluation of the kinetic of organic matter decay and the mineralization efficiency reaches 90% COD removal at only 200 mA for 300 min of electrolysis.
Hayat EL Ouafy; Tarik EL Ouafy; Mustapha Oubenali; Mohammed EL Idrissi; Malika Echajia; Aziz EL Haimouti; Mohamed Mbarki; Hassan Oulfajrite
Volume 12, Issue 2 , February 2020, , Pages 168-179
Abstract
Clay modified carbon paste electrode (CPE-C) its applicability for electroanalysis of N, N’-ethylene-2,2’-bipyridinium (diquat) has been described in the present work. Electrochemical modification was performed by electronic impedance spectroscopy (EIS) and cyclic voltammetry (CV) in the ...
Read More
Clay modified carbon paste electrode (CPE-C) its applicability for electroanalysis of N, N’-ethylene-2,2’-bipyridinium (diquat) has been described in the present work. Electrochemical modification was performed by electronic impedance spectroscopy (EIS) and cyclic voltammetry (CV) in the range of -0.6 V to 1.2 V in 0.1 M K2SO4 (pH 3). The voltammetric method behavior of DQ is suggested where an anodic and cathodic peak appeared at Epa=0.55 V and Epc=0.1 V, successively. These peaks obtained from the reversible redox of DQ at the CPE-C surface. The optimal preconcentration time and percentage of clay insert were 10 min and 20% respectively. The proposed method exhibits certainly an electro-catalytic success toward DQ redox. The peaks current recorded using cyclic voltammetry has been linearly dependent on the DQ concentration ranging from 1×10-5 to 5×10-5 molL-1. The detection limit (DL) calculated for the anodic peak is 5.33×10-8 molL-1. Then relative standard deviation for 2×10-5 molL-1 diquat has been 4.3% for nine repetitions. The proposed detector has been successfully applied for DQ electroanalysis in a river water sample with a DL of 8.17×10-8 molL-1.
Arash Fattah-alhosseini; Kazem Babaei
Volume 12, Issue 3 , March 2020, , Pages 301-317
Abstract
Mg alloys have a vast usage where weight reduction is really significant since they do the features really well for materials of ultra-light weight. However, Mg is inherently a reactive metal and its alloys generally possess quite weak corrosion resistance that widely restricts their technological usages, ...
Read More
Mg alloys have a vast usage where weight reduction is really significant since they do the features really well for materials of ultra-light weight. However, Mg is inherently a reactive metal and its alloys generally possess quite weak corrosion resistance that widely restricts their technological usages, especially in some rough service conditions. Despite, many investigations on the passive and electrochemical properties of Mg alloys and their relation with the microstructure of these alloys, few reports have been devoted to investigate the semiconducting behavior of the formed oxide layers on these alloys. Mott–Schottky measurement is a major in-situ technique to analyze semiconductor behavior of passive layers. In this review, the semiconducting properties of formed passive layers on Mg alloys (AZ91D, AZ31B, AZ80, Mg-Y-Rare Earth-Zr alloys) by Mott–Schottky measurement has been assessed. Mott–Schottky measurements revealed the formed passive films on Mg alloys show mainly n-type behavior regardless the microstructure, pH, immersion time, and temperature of electrolyte.
Caio Machado Fernandes; Thayssa da S. F. Fagundes; Nazir E. dos Santos; Bruno Sergio do Amaral; Quezia B. Cass; Alessandra L. Valverde; Júlio César M. Silva; Odivaldo C. Alves; Eduardo A. Ponzio
Volume 12, Issue 4 , April 2020, , Pages 437-457
Abstract
In the context of highly efficient, non-toxic and natural organic corrosion inhibitors, Phyllogorgia dilatata was studied as an anticorrosive for mild steel in acid medium. The marine octocoral crude extract (PDCE) was characterized and analyzed by LC-HRMS, revealing the presence of 16 different organic ...
Read More
In the context of highly efficient, non-toxic and natural organic corrosion inhibitors, Phyllogorgia dilatata was studied as an anticorrosive for mild steel in acid medium. The marine octocoral crude extract (PDCE) was characterized and analyzed by LC-HRMS, revealing the presence of 16 different organic molecules. The corrosion inhibition was evaluated via weight loss study and electrochemical techniques. The obtained polarization curves showed that PDCE acts as a mixed-type inhibitor and gravimetric, Electrochemical Impedance Spectroscopy and Linear Polarization Resistance analyses reached an average maximum anticorrosive efficiency of 93.4% at 1 g L-1. The data crossing between gravimetric and electrochemical measurements indicated that the protection mechanism is due to adsorption, blocking electro-active sites. The adsorption data followed the Freundlich theory and SEM/EDX images confirmed the formation of a protective multilayer film.
Soheyla Sharif Manesh; Mahboubeh Masrournia; Ali Beyram Abady
Volume 12, Issue 2 , February 2020, , Pages 180-192
Abstract
In the study, novel and sensitive carbon paste electrodes (CPEs) developed for thepotentiometric measurement of Cr(III) and Mg(II) ions in pharmacological and water samples.CPEs as indicator electrodes were prepared from a mixture of four components, includinggraphite powder, paraffin oil, multi-walled ...
Read More
In the study, novel and sensitive carbon paste electrodes (CPEs) developed for thepotentiometric measurement of Cr(III) and Mg(II) ions in pharmacological and water samples.CPEs as indicator electrodes were prepared from a mixture of four components, includinggraphite powder, paraffin oil, multi-walled carbon nanotubes (MWCNTs), and a greenionophore (Chitosan Schiff base derivative). Optimization of CPE composites indicated thatthe critical factor in the preparation of the CPEs was chitosan Schiff base derivative whichselectivity proposed sensors highly depended on this factor. Effects of various parameters suchas pH, lifetime, response time, and selectivity of the potentiometric sensors to determine Cr(III)and Mg(II) ions were also evaluated. The results indicated that the proposed sensors can beapplied in a relatively wide range of pH, long lifetimes, short response times, and excellentselectivity for the analyte determination. The prepared sensors show Nernstian slopes of 19.53and 29.83 mVdecade−1, and LODs of 5.6×10– 8 and 4.4×10−9 with RSDs lower than 2.3% forCr(III) and Mg(II) ion determination, respectively. The calibration curves were linear in theconcentration ranges of 1.0×10-7-1.0×10-2 and 1.0×10-8-1.0×10-3 M, and R-square of 0.989 and0.987 for the measurement of Cr(III) and Mg(II) ions, respectively. Besides, the sensors weresuccessfully utilized for the Cr(III) and Mg(II) ion measurement in real samples such as tabletand tap water samples with suitable recovery higher than 97.6%.
Vinod Kumar Vashistha; Deepak Kumar Das; Anubha Yadav; Deepak Saini; Anuj Kumar
Volume 12, Issue 3 , March 2020, , Pages 318-328
Abstract
Macrocycles and p-benzoquinones (p-BQ) have been generally connected as potential co-synergist redox models in aerobic oxidation. To get insight for the synergist oxidation of hydroquinones (H2Q), thus, we synthesized and characterized dibenzotetraaza [14]annulene type macrocycles of FeIII and CoII metal ...
Read More
Macrocycles and p-benzoquinones (p-BQ) have been generally connected as potential co-synergist redox models in aerobic oxidation. To get insight for the synergist oxidation of hydroquinones (H2Q), thus, we synthesized and characterized dibenzotetraaza [14]annulene type macrocycles of FeIII and CoII metal ions and described by utilizing different examinations including molar conductance, IR, UV-Vis, mass and cyclic voltammetric measurements. The spectroscopic and computational studies proposed that the macrocycles have saddle shape distorted octahedral structure. These macrocycles demonstrated the reversible and quasi-reversible redox process pursued by Randles-Sevcik equation, demonstrating the adjustment of unusual oxidation conditions of metal ions. Further, the experimental consequences presented herein enlighten the catalytic activity of these macrocycles towards the oxidation of H2Q. The results indicated that in the absence of macrocycles, the molecular oxygen is inactive with H2Q but in presence of synthesized macrocycles H2Q initiates prompt oxidation with the production of H2O2. Moreover, CoII macrocycle was found to be an efficient catalyst for the oxidation of H2Q into corresponding benzoquinones.
Ebrahim Naghian; esmail sohouli
Volume 12, Issue 4 , April 2020, , Pages 458-467
Abstract
Zolpidem is a drug that is easily attached to the GABA receptors in the brain. This property makes it very effective for tranquilizing as well as hypnagogia. According to the advantages of electrochemical analysis like high selectivity, high sensitivity, low concentration of analyte, cost-effective, ...
Read More
Zolpidem is a drug that is easily attached to the GABA receptors in the brain. This property makes it very effective for tranquilizing as well as hypnagogia. According to the advantages of electrochemical analysis like high selectivity, high sensitivity, low concentration of analyte, cost-effective, portable and easy-to-use setup, they gained high amount of attention among scientists for determination of different compounds. So in the work, an electrochemical sensor was prepared by the modification of a carbon paste with sulfur-tin@tin oxide nanocomposite (SnS@SnO2NP/CPE) and was investigated for the determination of zolpidem in an aqueous solution. For this reason the electrochemical characteristic of SnS@SnO2NP /CPE including cyclic voltammetry and electrochemical impedance techniques were used. Cyclic voltammetry studies indicated that the process was irreversible. Determination of zolpidem was performed using differential pulse differential technique at the modified electrode surface and linear relationship of oxidation peak current with concentration of this drug show a LOD of 0.66 μM was in the range of 2-80 μM.
Moha Afrokh; Said Baroud; Mohamed Rbaa; Issam Sadki; Abdelhakim Hatimi; Saida Tahrouch; Mohamed Tabyaoui; Abdellah Guenbour; Ismail Warad; Abdelkader Zarrouk
Volume 12, Issue 2 , February 2020, , Pages 193-207
Abstract
This study set out to examine the cystoseira gibraltarica extract (CG) as an environmentally sustainable corrosion inhibitor for carbon steel in 1.0 M HCl medium. The corrosion inhibiting effect has been studied by conventional methods such as gravimetric (weight loss) and electrochemical (EIS and PDP) ...
Read More
This study set out to examine the cystoseira gibraltarica extract (CG) as an environmentally sustainable corrosion inhibitor for carbon steel in 1.0 M HCl medium. The corrosion inhibiting effect has been studied by conventional methods such as gravimetric (weight loss) and electrochemical (EIS and PDP) methods. All the methods used in this study confirm that cystoseira gibraltarica extract has a potential inhibitory effect of carbon steel in hydrochloric acid medium. The inhibitory efficiency reached at a maximum value of 90.3% at a concentration of 0.8 g/L, this efficiency was slightly decreased at high temperature. The results obtained by the polarization show that this ecological inhibitor acts as a mixed inhibitor. The parameters thermodynamics show that the studied inhibitor is adsorbed on the metal surface following Langmuir isotherm.
Faiza Kakaa; Mosbah Ferkhi; Mesbah Lahouel
Volume 12, Issue 3 , March 2020, , Pages 329-344
Abstract
The objective of this work was to demonstrate the effect of fluoride and propolis extract on the corrosion behavior of commercially pur titanium (cp-Ti grade 2) in artificial saliva. The inhibition studies were approved out on cp-Ti as dental implant in Fusayama-Meyer with the propolis extract using ...
Read More
The objective of this work was to demonstrate the effect of fluoride and propolis extract on the corrosion behavior of commercially pur titanium (cp-Ti grade 2) in artificial saliva. The inhibition studies were approved out on cp-Ti as dental implant in Fusayama-Meyer with the propolis extract using potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS). Parameters, such as concentration of the inhibitor, time of immersion were varied and optimized. The results showed that either the NaF or the presence of propolis extract in medium saliva had a significant influence on the corrosion rate (Icorr) and polarization resistance (Rp): the Icorr value increased and Rp decreased in medium containing fluoride, but the presence of propolis in media improved the corrosion resistance of this metal.
Negar Mohammadi; Manochehr Bahmaei; Amirabdolah Mehrdad Sharif
Volume 12, Issue 4 , April 2020, , Pages 468-485
Abstract
In this study, AuPdCu-rGO-MWCNTs nanocomposite was synthesised by a chemical reduction method which was applied to fabricate an electrochemical sensor for simultaneous determination Dopamine (DA), Acetaminophen (AC) and Tryptophan (Trp) by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) ...
Read More
In this study, AuPdCu-rGO-MWCNTs nanocomposite was synthesised by a chemical reduction method which was applied to fabricate an electrochemical sensor for simultaneous determination Dopamine (DA), Acetaminophen (AC) and Tryptophan (Trp) by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The formation of Au, Pd, and Cu nanoparticles on rGO-MWCNTs nanocomposite are characterized by XRD, FTIR, and SEM techniques. The relationship between the concentration of DA, AC, and Trp with the response of AuPdCu-rGO-MWCNTs/CPE was linear in the range of 10 nM to 8.3 μM, 20 nM to 12.5 μM and 10 nM to 9.4 μM by DPV technique, and 0.007-8.0, 0.011-11.6 and 0.008-8.8 μM by amperometric method, respectively. Also, the detection limits for DA, AC, and Trp were calculated to be 3, 7 and 4 nM, respectively by the voltammetric method and 2, 5 and 3 nM for DA, AC and Trp, by amperometric method. The investigations show that AuPdCu-rGO-MWCNTs/CPE has acceptable selectivity, stability, repeatability, and reproducibility. Finally, AuPdCu-rGO-MWCNTs/CPE was successfully applied to determine the analytes in the urine, blood plasma, and AC Tablet by desirable percentage of relative standard deviation and recovery.
Santosh B. Konnur; Sharanappa T. Nandibewoor
Volume 12, Issue 2 , February 2020, , Pages 208-222
Abstract
Electro analysis of 2-Aminothiazole (2-AT) by a low cost poly Glycine modified Pencil Graphite Electrode (poly Gly/PGE) was studied using of cyclic voltammetric (CV) and differential pulse voltammetric (DPV) techniques. The optimal experimental conditions to determine 2-AT was setup by the variation ...
Read More
Electro analysis of 2-Aminothiazole (2-AT) by a low cost poly Glycine modified Pencil Graphite Electrode (poly Gly/PGE) was studied using of cyclic voltammetric (CV) and differential pulse voltammetric (DPV) techniques. The optimal experimental conditions to determine 2-AT was setup by the variation of the current with scan rate, concentration and pH. Electrochemical performance of the 2-AT at poly Gly/PGE was found adsorption-controlled reaction. A plausible electro oxidation mechanism was proposed. The anodic peak current of DPV was found to be linearly proportional to the 2-AT concentrations in the range from 1.0×10-6 to 12.0×10-6 M with a detection limit 7.29×10-8 M with better selectivity and sensitivity under the optimal conditions. Quantitative analysis of 2-AT levels in urine as real sample was carried out by applying this proposed method. Moreover, some common interfering substances were used to the study of interference. The clinical and quality control laboratories can employ this method to determine 2-AT.
Rubin Gulaboski; Pavlinka Kokoskarova; Sofija Petkovska
Volume 12, Issue 3 , March 2020, , Pages 345-364
Abstract
In this review, we focus on cyclic voltammetry as a reliable electrochemical technique to study mechanisms, kinetics and thermodynamics of various types of drug-drug interactions. While we present and discuss six theoretical models relevant to analyze drug-drug (or drug-DNA) interactions, we also give ...
Read More
In this review, we focus on cyclic voltammetry as a reliable electrochemical technique to study mechanisms, kinetics and thermodynamics of various types of drug-drug interactions. While we present and discuss six theoretical models relevant to analyze drug-drug (or drug-DNA) interactions, we also give hints about recent experimental achievements in this field. In addition, we provide the readers several sets of simulated voltammograms and data in tabular form, which can be used to recognize particular mechanism of drug-drug interactions in cyclic voltammetry. Moreover, we give hints to the voltammetric procedures that allow access to kinetics and thermodynamics parameters, which are relevant to various types of drug-drug interactions. The results we present in this work can be of big help to the scientists working in the field of pharmacy, pharmacology, medicinal chemistry and bio-electrochemistry.
Ali Babaei; Akbar Yousefi
Volume 12, Issue 4 , April 2020, , Pages 486-501
Abstract
In this study a novel method was developed to fabricate cadmium sulfide nanoparticles/multiwalled carbon nanotubes composite modified gold electrode (CdSNPs/MWCNTS/AuE) to measure trace amounts of norepinephrine(NE), indomethacin (IND), and uric acid (UA) simultaneously. Electrochemical investigations ...
Read More
In this study a novel method was developed to fabricate cadmium sulfide nanoparticles/multiwalled carbon nanotubes composite modified gold electrode (CdSNPs/MWCNTS/AuE) to measure trace amounts of norepinephrine(NE), indomethacin (IND), and uric acid (UA) simultaneously. Electrochemical investigations were carried out using cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamprometery (CA) methods. Using DPV method under optimum condition, the NE anodic peak current represented a linear relationship in the two concentration ranges of 0.3 to 100.0 μM and 100.0 to 500.0 μM. For UA, the corresponding anodic peak current showed linear ranges from 0.5 to 100.0 μM and from 100.0 to 350.0 μM, and IND the corresponding linear range was between 2.0 to 80.0 μM, respectively. Detection limits have been calculated equal to 0.16 μM for NE, 0.09 μM for UA, and 0.46 μM for IND, respectively. The modified electrode has been applied for the determination of NE, UA and IND in human urine and blood serum with satisfactory results.
Ahmed A. Habib; Hassan A. M. Hendawy; Sherin F. Hammad; Lories I. Bebawy; Marian A. Girges
Volume 12, Issue 2 , February 2020, , Pages 223-237
Abstract
The electrochemical behavior of tetrahydrozoline (THZ) was explored by cyclic voltammetry and differential pulse voltammetry. A well-defined peak at 915 mV using gold nanomodified electrode (AuNPts/CP) in presence of sodium dodecyl sulphate (SDS) was detected. Different buffers, pH and scan rates on ...
Read More
The electrochemical behavior of tetrahydrozoline (THZ) was explored by cyclic voltammetry and differential pulse voltammetry. A well-defined peak at 915 mV using gold nanomodified electrode (AuNPts/CP) in presence of sodium dodecyl sulphate (SDS) was detected. Different buffers, pH and scan rates on oxidation peak current were studied. Linear calibration curve was achieved in the range of 1.99×10−5 to 7.79×10-5 M with a limit of detection (LOD) 5.54×10-6 M and limit of quantification (LOQ) 1.69×10−5 M, respectively.The suggested method was successfully utilized to the eye drops dosage form and urine sample with percentage recovery, 98.86%±0.77, and 101.13±0.62, respectively.
Ameneh Amani; Mahdi Jamshidi
Volume 12, Issue 3 , March 2020, , Pages 365-375
Abstract
Electrochemical oxidation of leaves extract of lemon verbena and the flowers extract of echium amoenum have been studied in the absence and presence of barbituric acid and 1,3 dimethyl barbituric acidin aqueous solutions and biological pH, using cyclic voltammetry method. The results showed that the ...
Read More
Electrochemical oxidation of leaves extract of lemon verbena and the flowers extract of echium amoenum have been studied in the absence and presence of barbituric acid and 1,3 dimethyl barbituric acidin aqueous solutions and biological pH, using cyclic voltammetry method. The results showed that the electrochemically generated compounds in leaves extract of lemon verbena and the flowers extract of echium amoenum, participate in the chemical reaction with barbituric acid and 1,3 dimethyl barbituric acid. Based on our results, leaves extractof lemon verbena and the flowers extract of echium amoenum have a high antioxidant activity in comparison with galic acid, salicylic acid and quercetin as standard antioxidants and simultaneous can be useful for the treatment of barbiturate poisoning before starting clinical treatments. The antioxidant activity of luteoline and verbascoside (as the main and natural compounds in lemon verbena) against some of the reactive oxygen species (ROS) generation enzymes, Cytochrome P450 3A4 (4D75), Myeloperoxidase (1DNW) and Thyosine (3nm8) has been performed through molecular docking studies. The results indicated that these natural compounds bound exclusively to the binding site of ROS generation enzymes and has a remarkable role in suppressing the destructive effects of oxidative stress in the biological system of the human body.
Aya T. Soudi; Ola G. Hussein; Eman S. Elzanfaly; Hala E. Zaazaa; Mohamed Abdelkawy
Volume 12, Issue 4 , April 2020, , Pages 502-516
Abstract
Direct drug determination without any pervious treatment steps is the most environmentally friendly method of analysis. Traditional analysis methods usually involve a pre-treatment step before analysis and this consumes time and organic solvents. This work describes direct potentiometric method by using ...
Read More
Direct drug determination without any pervious treatment steps is the most environmentally friendly method of analysis. Traditional analysis methods usually involve a pre-treatment step before analysis and this consumes time and organic solvents. This work describes direct potentiometric method by using ion selective electrode to determine Montelukast Sodium in its pure drug substance and in tablet formulation and for inline monitoring of its release from its tablet form without any sample pretreatment. A Sensor was fabricated using PVC based membrane containing tetradodecyl ammonium bromide (TDB) being as an anionic exchanger and 2-nitrophenyl-octyl-ether (2-NPOE) being a plasticizer. The validation of the proposed method was done according to International union of pure and applied chemistry recommendations, in which the proposed sensor show a linear dynamic range from 1.0×10-6 to 1.0×10-2 mol/L. The proposed sensor was applied to determine Montelukast sodium in bulk powder, tablets dosage form with no extraction. The sensor was also used as bench-top real-time analyser for in process tracking of Montelukast sodium concentration during monitoring of its dissolution behaviour, under U.S. Food and Drug Administration dissolution regulations, with clear discrimination from its common excipients. Results obtained by the proposed potentiometric method were compared with those obtained by the official HPLC method.
Shokoofeh Sheibani; Seyed Iman Mirzaie; Mehdi Fardmanesh; Parviz Norouzi
Volume 12, Issue 2 , February 2020, , Pages 238-249
Abstract
A novel recognition method for selective determination of the hyoscine N-Butyl bromide (HBB), an antispasmodic agent for smooth muscles, was devised using extended gate field-effect transistor (EG-FET) as transducing unit. For this purpose a PVC membrane, containing hyoscine n-butyl-tetraphenyl borate ...
Read More
A novel recognition method for selective determination of the hyoscine N-Butyl bromide (HBB), an antispasmodic agent for smooth muscles, was devised using extended gate field-effect transistor (EG-FET) as transducing unit. For this purpose a PVC membrane, containing hyoscine n-butyl-tetraphenyl borate ion-pair as recognition component, was coated on Ag/AgCl wire, which was connected to the extended metal gate. In optimal conditions, the linear range for HBB was 10-8-10-5 molL−1 with limit of detection 1.7×10-9 molL-1. The proposed sensor was applied in real sample, it showed fast response with high accuracy, and therefore it could be used as HPLC detector in the pharmaceutical samples in quality control.
Esmat Shojaeia; Mahboubeh Masrournia; Ali Beyramabadi; Hossein Behmadi
Volume 12, Issue 3 , March 2020, , Pages 376-391
Abstract
The strontium ion, in water-soluble forms, is one of the major pollutant in drinking water. Therefore, a simple, rapid, selective, and sensitive potentiometric carbon paste electrode was developed to measure strontium ion in real samples with complex matrices. To prepare the potentiometric sensor, a ...
Read More
The strontium ion, in water-soluble forms, is one of the major pollutant in drinking water. Therefore, a simple, rapid, selective, and sensitive potentiometric carbon paste electrode was developed to measure strontium ion in real samples with complex matrices. To prepare the potentiometric sensor, a synthetic ligand ((E)-4-(((2-amino-4-chlorophenyl)imino)methyl)-5-(hydroxymethyl)-2-methyl pyridine-3-ol) as an efficient ionophore and an ionic liquid (1-Butyl-3-methylimidazolium hexafluorophosphate) as a suitable binder were dispersed in a mixture of graphite powder and graphene oxide. The composition of the sensor was optimized using a central composite design (full factorial) to reduce the number of experimental runs and investigate interactions between effective factors. The proposed sensor showed a Nernstian behavior in the linear concentration range of 1×10-8 to 1.0×10-1 M with a low detection limit (1.59×10−9 M) and suitable relative standard division (1.01 %). The proposed sensor can be well applied in the pH range of 3.00-9.50 for the analyte determination. Moreover, the proposed electrode as an indicator electrode was successfully used to measure the Sr(II) concentration in the depilatory powder, toothpaste, and raticide samples.
Arash Fattah-alhosseini; Maryam Molaei; Kazem Babaei
Volume 12, Issue 4 , April 2020, , Pages 517-535
Abstract
Recently, PEO process of tantalum has been developed as a method of producing corrosion-resistant, hard, wear-resistant, and biocompatible as well as having good adhesion coatings. In this review, we present the results of PEO process of tantalum in three main electrolytes. This review tries to measure ...
Read More
Recently, PEO process of tantalum has been developed as a method of producing corrosion-resistant, hard, wear-resistant, and biocompatible as well as having good adhesion coatings. In this review, we present the results of PEO process of tantalum in three main electrolytes. This review tries to measure the effect of electrolyte composition and voltage that were used within PEO procedure on the surface behavior of the produced oxide coatings on Ta. The results of the PEO treatment of Ta in H4SiW12O40 electrolyte revealed that the morphology of oxide coatings really depends on the PEO procedure time. Density of discharge channels declines as their diameter rises. This leads to an increase in the oxide coating roughness within the PEO procedure of tantalum. In electrolytes of β-glycerophosphate disodium and calcium acetate, the results indicated that the employed voltage significantly affected morphologies, the coatings bond strength and the phase components. However, it affected surface chemical species a little. Finally, in 0.5 M Ca (H2PO2)2 electrolytes, the results revealed that using a precise control on the procedure voltage, tuning the obtained coatings thickness is possible in addition to their roughness, adhesion strength and relative values of the electrolyte type inside the modified surfaces of tantalum.
Taher Alizadeh; Somayeh Amjadi
Volume 12, Issue 2 , February 2020, , Pages 250-262
Abstract
The foregone studies have shown that nicotinic acid cannot produce noticeable reductive signal at carbon-based electrodes without appropriate modification of the electrode. This is an obvious reason that mercury is known as the main electrode material for electro-reduction of nicotinic acid. In this ...
Read More
The foregone studies have shown that nicotinic acid cannot produce noticeable reductive signal at carbon-based electrodes without appropriate modification of the electrode. This is an obvious reason that mercury is known as the main electrode material for electro-reduction of nicotinic acid. In this study, it has been shown that it is possible to create a remarkable reduction signal for NA at a carbon paste electrode (CPE) without any modification. This achieved by precisely adjustment of electroanalysis pH, appropriately choosing of binder kind, precisely controlling of the percentage of the binder in the electrode composition and utilizing of an effective voltammetric technique. A carbon paste electrode, containing 30% of n-eicosane (as binder) was shown to be the best electrode for NA determination. It was also shown that utilizing of square wave voltammetry in place of differential pulse voltammetry led to remarkably improvement in the analytical signal of NA. The pH value of the electroanalysis solution was shown to be a crucially effective factor for creating of NA signal and an optimum value of pH equal to 2.2 was chosen as the best pH condition. The optimized method exhibited a dynamic concentration linear range of 3.0×10−6-3.0×10−3 molL-1 with a detection limit of 5.63×10−7 molL-1. As an analytical application, the proposed sensor was successfully used for determination of nicotinic acid in the urine, serum and pharmaceutical samples.
Baha Öndeş; Mihrican Muti
Volume 12, Issue 3 , March 2020, , Pages 392-401
Abstract
Disposable, selective and low-cost carbon nanotube modified electrodes were fabricated for the electrochemical detection of neonicotinoid insecticide, Clothianidin (CLT). Almost 2 folds’ increase at Clothianidin reduction signal was obtained by using single-walled carbon nanotube modified electrodes ...
Read More
Disposable, selective and low-cost carbon nanotube modified electrodes were fabricated for the electrochemical detection of neonicotinoid insecticide, Clothianidin (CLT). Almost 2 folds’ increase at Clothianidin reduction signal was obtained by using single-walled carbon nanotube modified electrodes (SWCNT-PGE) compared to unmodified electrodes. These nanomaterials modified electrodes developed in this study will enable simple, rapid and inexpensive identification of the neonicotinoid insecticides, Clothianidin and it is hoped that this technique developed by using these nanosensors will be an alternative to the expensive and time consuming chromatographic techniques with its advantages of adapting to the sensor chip technology for the routine analysis of agricultural products.
Atieh Zabihollahpoor; Mostafa Rahimnejad; Ghasem Najafpour-Darzi; Ali Akbar Moghadamnia
Volume 12, Issue 4 , April 2020, , Pages 536-552
Abstract
Herein, gold nanoparticle had been successfully synthesized through a simple, inexpensive and clean electrochemical technique. Gold nanoparticles were directly deposited on the electrode surface using an electrochemical strategy. Then, the electrochemical deposition parameters (such as applied potential ...
Read More
Herein, gold nanoparticle had been successfully synthesized through a simple, inexpensive and clean electrochemical technique. Gold nanoparticles were directly deposited on the electrode surface using an electrochemical strategy. Then, the electrochemical deposition parameters (such as applied potential and deposition time) were optimized. 1.1 V and 250 s were applied as the optimal electrodeposition potential and time in the rest of the investigations. The fabricated electrode was morphologically characterized by field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy methods. Under the optimized condition, the proposed sensor demonstrated the lowest detection limit (7.04 nM) in the linear range of 0.01–1 μM obtained by differential pulse voltammetry. The electrochemical properties of fabricated modified electrode were investigated by a different techniques such as cyclic voltammetry, linear sweep voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy. The constructed electrode also showed a negligible response from common interferences and the fabricated sensor was applied for Gabapentin analysis in pharmaceutical samples.
Hamid Reza Naderi; Ali Sobhani-Nasab; Esmail Sohouli; Kourosh Adib; Ebrahim Naghian
Volume 12, Issue 2 , February 2020, , Pages 263-276
Abstract
Nanoparticles of ytterbium tungstate prepared through the direct addition of an Yb3+ solution to a tungstate solution, were computed through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS). Further the supercapacitive characteristics ...
Read More
Nanoparticles of ytterbium tungstate prepared through the direct addition of an Yb3+ solution to a tungstate solution, were computed through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS). Further the supercapacitive characteristics of the nanoparticles, as a potential material for constructing electrodes, were evaluated through cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS). Electrodes made of the Yb2(WO4)3 had a specific capacitance (SC) value of 336 F g-1 in a 2.0 M H2SO4 solution at a potential scan rate of 2 mV s-1; and 298 F g-1 at a current density of 1 A g-1 based on GCD tests. The electrodes also revealed to have a 95.8% cycling durability after 4000 potential cycles.
