Spectroscopic, Voltammetric, DFT and Molecular Docking Studies of Copper (II) Complex of Carbothiohydrazide Derivative

In this work, the nature of complexation between copper and N′,2-bis((E)-2-hydroxybenzylidene) hydrazine-1-carbothiohydrazide (a promising metal sensing Schiff base with a marked biological activity) (H4L) has been investigated and experimentally characterized. The investigation includes spectroscopic tools as infrared spectra (FT-IR), XRD, thermal analysis (TG) spectra, ultraviolet spectra (UV) in addition to cyclic voltammetric study. Quantum chemical calculations using density functional theory (DFT) used to predict the structural properties of the complex under investigation and to aid in the explanation of the electronic spectra of the complex. In addition to that, the Molecular docking for the complex under investigation with the 2ylh target protein have been conducted in order to check the biological activity of the complex.

CuCrO4 Nanoparticles Composite Modified Carbon Paste Electrodes for Sensitive Detection of Paracetamol: A Cyclic Voltammetric Study

An electrochemical sensor containing carbon paste electrode (CPE) for paracetamol is developed and modified with the CuCrO4 Nanocomposites. The synthesised CuCrO4 Nanocomposites was discussed with X-Ray Diffraction studies. Experimental studies such as scan rate, concentration and pH was studied by using cyclic voltammetric method. The CuCrO4 Nanocomposites modified CPE (CuCrO4 Nanocomposites MCPE) exhibited excellent electrocatalytic response towards the oxidation of paracetamol (PC). Over potential for oxidation of PC was minimised which considerably enhance the current response on the CuCrO4 Nanocomposites MCPE when compared with bare carbon paste electrode (BCPE). Scan rate study for PC discuss the process of the electrode. Linear calibration curve was obtained with the range of 2 μM to 14 μM having the detection limit and quantification limit value of PC is discussed with CuCrO4 Nanocomposites MCPE. This study shows that electrochemical oxidation of PC at CuCrO4 Nanocomposites MCPE is pH dependent process.

Synthesis, Electrocatalytic and Gas Transport Characteristics of Pentagonally Structured Star-Shaped Nanocrystallites of Pd-Ag

The method of synthesis of bimetallic Pd–Ag pentagonally structured catalyst “nanostar” on the surface of Pd-23%Ag alloy films has been developed. The resulting catalyst was studied as a highly active functional layer for methanol oxidation reaction (MOR) in alkaline media and the intensification of hydrogen transport through the Pd-23%Ag membrane in the processes of hydrogen diffusion purification. A modifying layer with a controlled size, composition and excellent electrocatalytic activity was synthesized by electrochemical deposition at a reduced current density compared to classical methods. The low deposition rate affects the formation of pentagonally structured nanocrystallites, allowing Pd and Ag particles to form well-defined structures due to the properties of the surfactant used. Electrochemical studies have demonstrated that the catalyst synthesized by the “nanostar” method shows better electrocatalytic activity in relation to MOR and demonstrates a higher peak current (up to 17.82 µA cm−2) in comparison with one for the catalyst synthesized by the “nanoparticle” method (up to 10.66 µA cm−2) in a cyclic voltammetric study. The nanostar catalyst electrode releases the highest current density (0.25 µA cm−2) for MOR and demonstrates higher catalytic activity for the oxidation of possible intermediates such as sodium formate in MOR. In the processes of diffusion membrane purification of hydrogen, a multiple increase in the density of the penetrating flux of hydrogen through the membranes modified by the “nanostar” catalyst (up to 10.6 mmol s−1 m−2) was demonstrated in comparison with the membranes modified by the “nanoparticles” method (up to 4.49 mmol s−1 m−2). Research data may indicate that the properties of the developed pentagonally structured catalyst “nanostar” and its enhanced activity with respect to reactions involving hydrogen increase the desorption activity of the membrane, which ultimately accelerates the overall stepwise transfer of hydrogen across the membrane.

Electrochemical study of Nickel Oxide (NiO) nanoparticles from cactus plant extract

ABSTRACTP-type NiO powders with an average crystallite size of 16 nm as shown by x-ray diffraction analysis were produced via biosynthesis using cactus plant extract. SEM showed that the NiO powders consisted of particles with sizes in the 20-35 nm range. A cyclic voltammetric study of the NiO nanopowders showed a quasi-reversible redox processes with the NiO powder showing potential for pseudo capacitance. Through these findings the use of natural Cactus extracts is hereby shown to be a cost-effective and environmentally friendly alternative for preparing Nickel oxide nanosized powders that can be of use in a variety of energy storage applications.

A New Electrochemical Sensor for Direct Detection of Purine Antimetabolites and DNA Degradation

The development of a reliable electrochemical sensor using a hybrid nanocomposite consisting of ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) functionalized graphene oxide (GrO-IL) and gold nanoparticles (AuNPs) stabilized by chitosan (Chit) was described. The new sensor, labelled as GrO-IL-AuNPs-Chit/CSE, exhibited an improved electrocatalytic response to cancer drugs such as purine antimetabolites (6-thioguanine, 6-mercaptopurine, and azathioprine) in a wide concentration range with a low detection limit (20–40 nmol·L−1, S/N = 3), and satisfactory recoveries (97.1–103.0%). The sensor has been also successfully used for cyclic voltammetric study of a salmon sperm double-stranded DNA degradation and DNA-6-mercaptopurine interaction in aqueous solutions (pH 7.4).