Analytical & Bioanalytical Electrochemistry
Volume:14 Issue: 6, Jun 2022

Organic molecules have occupied an important place by researchers and chemists in the field of corrosion inhibition of metals in various corrosive media such as HCl. Owing to the property of adsorption on the metal surface by the interaction of heteroatoms (O, N, P, S), rings, and double bonds exist in the molecules with the vacant orbital on a metallic surface. These interactions lead to the adsorption of molecules on the metal surface, forming an inhibitory layer, thus decreasing the corrosion rate of the metal, and increasing the inhibition efficiency. The review begins with a history of corrosion inhibitor molecules, then the effect of structure, substitution, heteroatoms, and chain length existing in the molecules on the inhibition efficiency. Comparative study of the inhibitory performance of corrosion inhibiting molecules using weight loss (WL), electrochemical impedance spectroscopy (EIS) techniques, and Potentiodynamique polarization (PDP). Adsorption isotherm models and global quantum chemical descriptors (GQCD) were applied to understand the relation between inhibition efficiency and molecular structure. This summary investigates and evaluates specific organic molecules and their inhibition efficiency in corrosive environments.

The invaluable advantages of smart nanomaterials are being explored in several fields nowadays which have made the nanomaterials applicable in sensing pharmaceuticals products at different concentrations in various media including nanomedicine, drug innovation, and delivery, and water treatment plants. Pharmaceutical detection in the food sector, biomedical diagnostics, and water monitoring are very cogent owing to the risks associated with the composition of these drugs when existing above permissible limits in a matrix. Therefore, this review summarizes the recent research activities on the use of smart nanomaterials for sensing pharmaceuticals in various mediums. Classifications and synthesis of various nanomaterials are also discussed. Lastly, the application of smart nanomaterials in sensing pharmaceuticals in various matrices was also reviewed. It is expected that this review will guide towards tailoring nanomaterials for sensing pharmaceuticals in different matrices and for possible improvement on their applicability.

In this report, different voltammetric tools such as cyclic, linear sweep, and square wave voltammetry were used to investigate acebutolol, a -blocker type of drug that is used to treat a variety of ailments, including cardiovascular disease, using a carbon paste electrode (CPE) under physiological environment. Under various phosphate buffer solutions, the voltammetric behavior of acebutolol displays two oxidation peaks and one reduction peak potentially within the range of -0.2 to 1.4 V, optimum results were obtained for pH 7.0. The electrode reaction was accompanied by two protons and two electrons transferred respectively; a probable electro-oxidation pathway has been proposed. The square wave voltammetric technique (SWV) was applied to perform a quantitative analysis of acebutolol. The linearity range was found to be between 0.06-10 µM. The LOD and LOQ were 2.06 nM and 6.88 nM, respectively which were superior to earlier methods. Furthermore, the new approach was used to determine the amounts of acebutolol in biological samples.

The stability constants of ion-ionophore complexes can determine the selectivity of ion-selective electrodes. In this study, the quantitative structure-property relationship (QSPR) model was employed to predict the complex stability constants of lead ions with different ionophores. The Genetic algorithm-multiple linear regression method (GA-MLR) developed models based on calculated molecular descriptors. Y-randomization testing, cross-validation, and test set compounds were applied to evaluate the predictive ability of the built model. This built model obtained high statistical quantities (R2train= 0.899, R2adj = 0.877, Q2LOO = 0.831, Q2LOO = 0.776, and Q2boot = 0.780) and showed that GA-MLR was a promising tool to predict the complexation stability of pb2+ with different ionophores. The current study introduces an efficient model for testing and assessing selectophores in lead-selective sensors based on complex stability constants. Additionally, this model could guide the design of highly selective ionophores for Pb (II) sensors.

This work is devoted to the electrodeposition of Cu2O on copper-substrate (Cu) by linear-sweep-voltammetry (LSV) method at short time of deposition (10 min) and a bath temperature of 50 °C. The influence of potential value ({E1} = {-100; -200 mV}; {E2 = -200; -300 mV}, {E3 = -300; -400 mV}, {E4= -400; -500 mV}, {E5 = -500; -600 mV} and {E6 = -600; -700 mV}) on structural, optical, and morphological properties of the electrodeposited Cu2O thin-films on Cu-substrate were investigated. The synthesized Cu2O thin films were analyzed by several techniques such as Raman-spectroscopy, X-ray-diffraction, UV-vis measurements and FEG-Scanning-Electron-Microscopy (FE-SEM-EDS). The X-ray-Diffraction has revealed that the electrodeposited thin-films correspond well to the cubic structure (Pn3 ̅m) and has revealed the good crystallinity for those deposited in the potential range -400 to 500 mV. Raman measurement confirm the cubic crystal structure (Pn3 ̅m) of the synthesized samples, all the thin-films have a high light absorption capacity in the visible spectrum and the estimated value of the optical gap are close to 1.9 eV.

Herein, two electrochemical methods are suggested for the determination of spiramycin (SPI) in pharmaceutical finished products. The first method is based on square wave voltammetric strategy (SWV) for the oxidation of SPI at a carbon paste electrode in a surfactant-containing electrolyte. Studying the cyclic voltammetry of SPI showed that the electrochemical oxidation process of SPI is irreversible with a peak current at 0.87 V in Britton- Robinson buffer (pH 9.0). Several important parameters including the influence of surfactants, the pH of the electrolyte and the rate of scan on the peak current were investigated. Under optimal experimental conditions, a linear response was obtained in the concentration range from 5 μM to 450 μM. The second method aims at the fabrication and characterization of a potentiometric homemade screen-printed electrode for the cost-effective determination of SPI. A Nernstian potentiometric response for SPI was achieved using potassium tetrakis (p-chlorophenyl) borate (KTpClPB) as a lipophilic ion exchanger in a polymeric PVC membrane over the concentration range from 1×10-6 to 1×10-2 M. However, the effect of membrane composition with respect to the ion exchanger and the plasticizers on the potentiometric response was remarked. The proposed voltammetric and potentiometric methods were successfully applied for the determination of SPI in bulk powder, in pharmaceutical formulations and monitoring SPI in natural water without extraction or sample pre-treatment.