Analytical & Bioanalytical Electrochemistry
Volume:16 Issue: 6, Jun 2024

Environmental issues have received considerable attention in recent years, and the use of green corrosion inhibitors has become the main topic of most researchers. The current study was focused on evaluating the essential oil from aerial parts of the Ruta Graveolens L. (RG-(EO)) has been used as an eco-friendly corrosion inhibitor on Mild Steel (MS) at 1 M HCl solution. The characterization method (i.e., gas chromatography-mass spectrometry (GC/MS)) identified 21 constituents representing 95.3% of the total amount and undecan-2-one (U2ONE) has been identified as the main constituent of RG-(EO). The inhibiting effect of RG-(EO) on the corrosion of MS in 1 M HCl solution was tested by the measurements of Weight loss (WL), potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) as well as quantum chemical calculation methods. The PDP test findings showed that the effectiveness of MS inhibition increased with the addition of the RG-(EO), reaching almost 94.80% at 2.00 g/L. The thermodynamic analysis showed that the inhibition efficiency increases slightly with an increase in the temperature of the medium (308-343 K). Moreover, the thermodynamic kinetic parameters showed that the adsorption of RG-(EO) on MS surface sites is subject to the Langmuir adsorption isotherm. Finally, the theoretical studies based on quantum chemical analysis (i.e. density functional theory (DFT)) and Monte Carlo (MC) simulation were also performed for understanding the adsorption mechanism of U2ONE onto Fe-surface.

The pyrazole derivatives and its metal complexes are considered to be pharmacologically significant with a variety of pharmacological applications. The present investigation highlights the synthesis of pyrazole based novel ligand, 4-[(E)-(3-hydroxypyridin-2-yl)diazenyl]-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one (PDP) and its Co(II), Ni(II), Cu(II) complexes. The structure of the synthesized compounds has been evaluated using various physicochemical and spectroscopic techniques. Cyclic Voltammetry (CV) results are used to confirm the electrocatalytic ability of the modified electrode, [Co(PDP)2]Cl2.2H2O/GCE for the detection of Folic acid (FA) at different concentrations. The CV results displayed good electro-catalytic activity with 10-120 µML-1 with limits of detection (LOD) of 0.0666 µML-1. This electrode has a sensitivity of 2.8784 µAµM-1cm-2 for FA. The bio-efficacy of the synthesized ligand and its complexes have been evaluated against the bacteria (S.aures and E.coli) and fungal (A.flavus and P.anomala) strains using standard method. Antidiabetic study on two different enzymes, α- amylase and α-Glucosidase indicating excellent inhibition by the metal complexes having the maximum IC50 Value of 105.34 for α-amylase and 107.15 mg/mL for α- Glucosidase.

Corrosion of mild steel is a disturbing phenomenon that deserves effective measures to avert accidents, equipment breakdown, and economic downturns. The corrosion inhibitory potentials of zinc oxide nanoparticles/tenofovir disoproxil fumarate nanocomposite (Z+D) was investigated using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS).  PDP analysis revealed that the alteration in corrosion potential values in the presence of Z+D (compared to corrosion potential obtained in the absence of Z+D) was less than 85 mV which suggest that Z+D operated as a mixed-type inhibitor. Corrosion current density (Icorr) decreased tremendously from 1241 μAcm-2 (in the absence of Z+D) to 321 μAcm-2 in the presence of 1000 ppm of the inhibitor. The inhibition efficiency increased with an increase in concentration of inhibitor to reach 74% when 1000 ppm of the inhibitor was introduced. EIS studies revealed a tremendous increase in charge transfer resistance (Rct) from 3533 Ω cm2 (in the absence of the inhibitor) to 21464×cm2 when 1000 ppm of Z+D was introduced. The highest inhibition efficiency (i.e 84%) computed from EIS analysis was obtained when 1000 ppm of the inhibitor was introduced. Electrochemical findings suggest that Z+D exhibited good attributes as a corrosion inhibitor for mild steel in 1 M hydrochloric acid.

This work reports on an inhibition and adsorption performance study of two quinazoline derivatives ((2-(2-chlorophenyl)-2,3-dihydroquinazolin-4(1H)-one) and (2-(2,4-dichlorophenyl)-2,3-dihydroquinazolin-4(1H)-one)) named ZB3 and ZB4, which were synthesized and examined using carbon nuclear magnetic resonance (13C NMR) and proton nuclear magnetic resonance (1H NMR) spectroscopy. The assessment of the corrosion prevention of these two compounds for MS in 1.0 M HCl was performed employing potentio-dynamic polarization (PDP) and (EIS) electronic impedance spectroscopy. The experiments performed showed that both derivatives operate well to prevent corrosion and their efficiencies exceed 85% at a concentration of 10-3. Moreover, it is discovered that the three chemicals' adsorption on the m-steel surface complies with Langmuir adsorption isotherm equation. The m-steel surface submerged in the corrosive solution was characterized by scanning electron spectroscopy (SEM) in conjunction with energy dispersive spectroscopy (EDS), spectroscopy using atomic force microscopy (AFM), X-Ray diffraction, and FTIR analysis. The findings showed that the examined inhibitors are well adsorbed, generating a barrier layer for the m-steel's surface. DFT calculations and Monte Carlo (MC) simulation were used to directly correlate the electronic and adsorption properties, respectively, with the experimental corrosion inhibition efficiencies obtained for quinazoline and its 2 investigated derivatives.

In the current effort, the nanoparticles of copper oxide (CuO/NP) were obtained by the co-precipitation procedure and characterized by the scanning electron microscope (SEM) X-ray powder diffraction (XRD), and energy dispersive spectroscopy (EDS) strategys. The CuO/MCPE was polymerized by utilising the N-Cetyl-N,N,N-trimethylammonium bromide (CTAB) surfactant, has been studied by cyclic voltammetric (CV) and linear sweep voltammetric (LSV) techniques. The analytical factors, such as pH, sweep rate, and concentration were evaluated. The limits of detection (LOD) and quantification (LOQ) was determined under optimized conditions and the values were arise to be 0.1179 µM, 0.391 µM, and 0.1942 µM, 0.6475 µM for Catechol (CC) and Hydroquinone (HQ), respectively. Moreover, the CuO/ pretreated CTAB/MCPE was employed for the sensitive and selective determination of CC and HQ in true samples.

Deep brain stimulation (DBS) is a surgical procedure that involves implanting a medical device to send electrical signals to specific brain areas to improve movement disorder symptoms. There are many efforts to introduce closed-loop-based stimulation in DBS therapy, but most are in the experimental stages.  The current study is the characterization of a hybrid electrode for closed-loop control of the DBS adaptive stimulations. The electrode is fabricated as an interdigitated woven model and accommodates current steering stimulation and a sensing mechanism to provide input for the adaptive close loop system.  The study incorporates the identification of damaging effects of stimulation, estimation of safe charge injection limits which eliminate tissue damage, and estimation of safe charge injection limits to minimise electrode damage through electrochemical analyses, including Cyclic Voltammetry, Electrochemical Impedance spectroscopy, and Chronopotentiometry.  The study also addresses the development of an appropriate electrical equivalent model that could be employed in later analytical studies. The study has derived that for an electrode (ø1.3mm×1.5mm) to safeguard against physiological mass action-induced damage, the maximum permissible charge injection per phase during stimulation should be set to Qma=2.08 µC, corresponding to a charge density of 33.98 µC/cm2. In the case of the Pt-10Ir electrode (ø1.3mm×1.5mm), the safe charge injection threshold to prevent damage from electrochemical reactions is established at 4.1 µC (at a rate of 67 µC/cm2), surpassing Shannon's tissue-damaging limit of 2.08 µC (at 33.98 µC/cm2).