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A highly specific design and synthesis of an α-Fe2O3@PEDOT core–shell nanoplatform for multifunctional gene/photothermal combination anti-cancer therapy.

The work herein describes the electrochemical detection of heavy metal ions, specifically cadmium and lead. The introduction and modification of functional groups such as Schiff bases leads to an enhanced sensitivity of the electrode to analytes. In this study, a platinum electrode has, for the first time, been modified with poly(3,4-ethylenedioxythiophene) (PEDOT/Schiff base) in CH2Cl2 containing Bu4NPF6 to detect cadmium(II) and lead(II) ions. The structures and morphologies of the polymer coatings were characterised via Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The electrochemical synthesis and redox state response in monomer-free synthesised films have been studied via cyclic voltammetry. Moreover, the effect of scan rate on the electrochemical behaviour of the modified electrodes was also studied. The voltammetric findings have been used to calculate the surface coverage required for the polymer films and the stability of polymer electrodes in the monomer-free solutions. Square wave voltammetry was applied for the determination of cadmium(II) and lead(II) ion concentrations and to assess the effects of pH on aqueous samples. The limits of detection for the modified electrode for cadmium(II) and lead(II) were found to be 0.95 μg L−1 and 1.84 μg L−1, respectively. These findings revealed that modified films can be considered good candidates for application in electrochemical detection devices.

In this study, a new type of multifunctional material PANI/NiO/MnO2 nanocomposite was first time prepared by chemical polymerisation from aniline monomer in the presence of metal oxides (NiO and MnO2) and an oxidant (ammonium persulfate) in acidic aqueous solution for the elimination of methyl orange (MO) dye from water. Herein, the PANI/NiO/MnO2 nanocomposite was found to be a favourable adsorbent for wastewater treatment due to its high adsorption and efficiency, self-regeneration, low cost and easy synthesis. Fourier transform infrared spectroscopy, X-ray diffraction, thermo-gravimetric analysis, transmission electron microscopy, scanning electron microscopy, Brunauer–Emmett–Teller analysis and Zeta potential were employed to characterise the synthesised nanocomposites. The data revealed that PANI nanocomposites doped with NiO and MnO2 nanoparticles had a higher adsorption efficiency (~ 97%) than that found in pure PANI (~ 53%). The adsorption conditions, such as pH of the medium, initial dye concentration, adsorbent dosage, and adsorption time were investigated. Various kinetic and isotherm models were used to analyse the results of the kinetics and the equilibrium adsorption and to interpret the interaction between the dye and nanocomposite adsorbents. The adsorption kinetics data for MO dye on the PANI/NiO/MnO2 were well explained based on a pseudo-second-order model while adsorption isotherm results were analysed based upon the Langmuir isotherm model. In addition, the adsorption process was an endothermic, favourable and spontaneous reaction according to thermodynamic studies. Also, the influence of matrix synthetic waste on MO dye removal was studied and found to show good results with matrix synthetic waste for both PANI/NiO/MnO2 and PANI adsorbents. The experimental adsorption capacity of the PANI/NiO/MnO2 nanocomposite (248.4 mg/g) was considerably greater than that of PANI (57.5 mg/g). The PANI/NiO/MnO2 adsorbent can be recycled up to four times and maintains a good adsorption capacity throughout.

The electrodeposition of cobalt from alternative electrolytes, including ionic liquids and deep eutectic solvents (DES), has become a topic of great interest to the scientific community, with a significant impact in both academic circles and in the development of commercial industrial electrochemical processes. However, very few studies have considered the effects of water on the electrodeposition of metals from deep eutectic solvents. In this work, the electrodeposition of Co from a choline chloride (ChCl) ethylene glycol (EG)-based deep eutectic solvent (DES) containing 10%, 20% and 30% water has been studied, and for the first time a uniform and bright Co deposit has been obtained when the deposition was achieved from an electrolyte containing 20% water. The speciation of Co in a mixed 1:2 ChCl:EG-based liquid (Ethaline 200) has been studied in both the absence and presence of water. The conductivities of the Co electrolyte were increased with increasing amounts of water. The electrochemical properties of the Co electrolytes have been studied using cyclic voltammetry, where it was found that the redox peak current gets larger and shifts in a positive direction when water was included in the Co solution. The resultant surface morphologies, topography, and roughness of the Co deposits were revealed by scanning electron microscopy (SEM) and atomic force microscopy (AFM), which demonstrated that a highly uniform and smooth cobalt coating had been produced when the deposition occurred in Ethaline 200 containing 20% water.

The use of additives to modulate metal electrodeposition from deep eutectic solvents has, to date, apparently been of little interest given the dearth of such studies in the literature. Here, we have actively investigated the effects of nicotinic acid (NA) on the electrodeposition of copper in a choline chloride (ChCl)-ethylene glycol (EG)-based deep eutectic solvent (DES), (1ChCl:2EG), considered a “green solvent” due to its physiochemical properties. Bright copper deposits were formed when NA was added to the Cu electrolyte, while a dull Cu deposit was produced in its absence. New Cu species were found to have formed in the 1ChCl:2EG-based liquid when NA was added to the electrolyte. A number of analytical techniques, in this instance cyclic voltammetry, chronoamperometry, and chronocoulometery, have been employed to determine the various electrochemical properties, nucleation mechanisms, and kinetics of the Cu species reported herein. The diffusion coefficient for the Ethaline-Cu system was found to be affected by the concentration of NA. An electrochemical quartz crystal microbalance (EQCM) was used to monitor the current efficiency of the copper deposition in both systems. The morphologies, thicknesses, roughnesses, and crystal structures of the copper electrodeposited from the NA-modified electrolyte were characterised via scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD), which between them demonstrate that the NA introduced into this system acts as a highly effective brightener, producing highly uniform and smooth copper deposits.

We report herein the electrochemical polymerisation of aniline from a choline chloride (ChCl)-based deep eutectic solvent (DES) at room temperature in both the presence and absence of deionised water in the solvent. The current study used Propeline as the DES electrolyte, which we found to be rich in protons (i.e. similar to protic ionic liquids) and which allowed the polymerisation of aniline in this system. The morphology of films was characterised by scanning electron microscopy (SEM) and atomic force microscopy (AFM), which showed the polymer film to have a compact structure and rough surface. The electrochemical quartz crystal microbalance (EQCM) was used for the first time to investigate the mass changes that occur during the electrochemical deposition of polyaniline (PANI) in situ, and was used to monitor cation, anion, and solvent transport when PANI films were immersed in pure Propeline and 0.5 M H2SO4 solution (monomer free) at 25 °C and 50 °C. In the case of the PANI exposed to pure Propeline at room temperature, the mass change increased continuously in both oxidation and reduction switching due to anion transfer dominating the mass change, while the PANI exposed to pure Propeline at 50 °C was found to form due to a two-step combined mechanism, showing excellent redox switching stability with changing mass. These variations in mass tend to be dominated by cation expulsion in the first oxidative process (the later reductive process being cation insertion) and by anion insertion in the second oxidative stage (the early reductive process being anion expulsion). In aqueous systems, the mechanism of mass change was dominated by anion movement associated with solvent transfer. The movement of neutral species in Propeline and water is in the reverse direction to those of cation or anion transfer.

The effects of nicotinic acid (NA), boric acid (BA) and benzoquinone (BQ) on the electrodeposition of Zn have been studied in a choline chloride (ChCl) ethylene glycol (EG) based deep eutectic solvent (DES), (1ChCl:2 EG), and for the first time a bright zinc coating has been achieved when NA was used. In metal electroplating processes, small-molecule additives are often included in the plating bath to improve properties of coating such as brightness, roughness, thickness, hardness and resistance to corrosion. The effects of additives on the electrodeposition of Zn from aqueous solution have been extensively investigated. However, very few studies have considered the effects of additives on the electrodeposition of Zn from ionic liquids or deep eutectic solvents. The electrochemical properties of the plating liquid have been studied here using cyclic voltammetry, chronocoulometry, chronoamperometry and microgravimetry (EQCM). Redox peak currents decrease when additives were included in the Zn solution and total charge was also reduced in experiments where additives were present. The Zn deposition in the absence of additive is in good agreement with an instantaneous growth mechanism at short experimental time scales (being indeterminate over longer periods), however, this changes to one of a progressive growth mechanism when additives were included in the coating bath. The current efficiency of zinc deposition in the DES without additives was 95%, which was reduced when additives were included. The resultant surface morphologies, thickness, topography, roughness and crystal structure of the Zn coating were revealed by scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray diffraction (XRD), demonstrating that those additives serve as effective brighteners that can produce highly uniform and smooth zinc deposits.

The work herein concentrates on the electrochemical detection of heavy metal ions, specifically cadmium and lead ions. The introduction and modification of functional groups such as Schiff bases had led to an enhanced sensitivity of the electrode to analytes. In this study, a platinum electrode has for the first time been modified with poly(3,4- ethylenedioxythiophene) (PEDOT/Schiff base) in CH2Cl2 containing Bu4NPF6 for use to detection cadmium (II) and lead (II) ions. The structure and morphology of the polymer coatings were characterised by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM), respectively. The electrochemical synthesis and redox state response in monomer-free synthesised films have been studied by cyclic voltammetry. Moreover, the effect of scan rate on the electrochemical behaviour of the modified electrodes was also studied. The voltammetric findings have been used to calculate the surface coverage required for the polymer films and the stability of polymer electrodes in the monomer-free solutions. Square wave voltammetry (SWV) was applied for the determination of cadmium (II) and lead (II) ion concentrations and to assess the effects of pH on aqueous samples. The limits of detection for the modified electrode for cadmium (II) and lead (II) were found to be 0.95 μg L-1 and 1.84 μg L-1, respectively. These findings revealed that modified films can be considered good candidates for application in electrochemical detection devices

Electroactive polymers such as polyaniline and its derivatives have many potential applications, but the nature of the dopants can have an adverse effect on their properties. Polyaniline (PANI), poly(o-methoxyaniline) (POMA) and poly(o-toluidine) (POT) have been synthesised using appropriate organic acid dopants (2-naphthalenesulfonic acid and 1,5-naphthalenedisulfonic acid) via electrochemical and chemical polymerisation methods, where the later was achieved at pH (1–2) in the presence of ammonium persulfate as an oxidant. The effects of the monomers and organic dopants on the physiochemical properties and morphological surface of the polymers were studied by means of Fourier transform infrared spectroscopy, electrical conductivity measurements, thermogravimetric analysis and scanning electron microscopy (SEM). The above films were also synthesised electrochemically whilst varying conditions such as scan rate, scan number and in aqueous solution of organic acids using cyclic voltammetry techniques. Cyclic voltammetry experiments have been employed to analyse the growth behaviour and electrochemical stability of films in the background electrolytes (monomer-free). It was found that PANI salts displayed higher doping levels and conductivity while POMA and POT salts were found to show lower conductivity and doping levels, respectively. Furthermore the electrochemical response of films was different in the stability and this may be because of the methoxy (–OCH3) and methyl (–CH3) groups located at the ortho position of the aromatic ring structure of the monomers (o-methoxyaniline and o-toluidine). The –OCH3 and–CH3 groups have significant steric effects and can reduce to form long chains of polymers and also decrease conductivity. The SEM showed that the morphologies of the prepared conducting polymers were different, which was associated with the nature and size of the dopant and monomer present in the bath solution.

In this work we report the created films of poly derivatives of aniline by using electropolymerization on platinum (Pt) electrode surface in non-aqueous electrolyte (Ethaline). The electropolymerization process of poly (3-amino benzoic acid) was happened in two electrolytes H2SO4 and HClO4 using a chronoamperometry (constant potential) technique for different times (50s, 100s, and 200s). All synthesized conducting polymer films were characterized by using FT-IR. Scanning electron microscopy (SEM) has been applied to study the morphologies of polymer samples. The electrochemical behaviour of prepared conducting films have studied by cyclic voltammetry. The overall findings shown that use a different electrolyte has led to the produce of various polymeric surface films as shown by scanning electron microscopy (SEM). Moreover, the charge consumed during the electropolymerization was calculated with time.

The optical properties of silver nitrates aqueous solution were investigated at different concentrations (1 x10-1, 1 x 10-2, 5 x 10-2 and 1 x 10-3 M). As well thin silver nitrate films of various thickness (210.76, 223.12, 241.56 and287.87 nm) were prepared via pulse laser deposition (PLD) technique using different laser pulses (250, 200, 150, 100 Pulses). Several optical characterizations were studied such as optical absorption properties, optical energy gap, absorption coefficient, extinction coefficient, index of refraction, reflectivity, transmission, optical conductivity and the real and imaginary electrical insulation constant. The results showed that, as one might expect, the absorption increases with increasing concentration of silver nitrate, while the transmission decreases. Furthermore, it has been observed that there is an increase in the absorption coefficient, extinction coefficient and coefficient of refraction as a function of photon energy with increasing the thickness of thin film, while the transmittance decreases with increasing thickness of the film. Also, the linear optical properties were calculated as a function of photon energy and found to increase with increasing thickness of the film. The optical energy gap was calculated for the allowed direct transfer of thin films different thicknesses and was found to decrease with increasing thickness.

This work will show, for the first time, the effect of nicotinic acid (NA) and 2-methylnicotinic acid (MNA)on the synthesis and properties of conducting polyaniline (PANI). The work investigates the effects of sulphuric acid (H2SO4), nicotinic acid (NA), and 2-methylnicotinic acid (MNA) on the synthesis and properties of polyaniline. The results show that the preparation of polyaniline from a sulphuric acid electrolyte is faster than the preparation from nicotinic acid and 2- methylnicotinic acid electrolytes. Moreover, the electrical conductivity and thermal stability of PANI/H2SO4 were greater than PANI/NA and PANI/MNA. All the polymers prepared in this study were identified using FT-IR. Scanning electron microscopy (SEM) was used to examine the morphologies of the PANI samples, from which it was determined that PANI/H2SO4 has a fibrous and open structure with a higher porosity morphology compared to PANI/NA and PANI/MNA. The electrical conductivities of the PANI samples were measured as 1.09 S cm-1, 0.65 S cm-1 and 0.089 S cm-1 for PANI/H2SO4, PANI/NA and PANI/MNA, respectively. The thermal stability of PANI was examined using the Thermogravimetric Analysis (TGA) technique. PANI/H2SO4 was found to degrade between 450-500°C, while PANI/NA and PANI/MNA decomposed at temperatures between 300-400°C.

Novel polyaniline (Pani) and/or graphite (Gr)/molybdenum dioxide (MoO2) composites have been successfully synthesised via an in situ chemical polymerisation method using a Deep Eutectic Solvent (DES) as the electrolyte. The chemical structure and properties of the Pani composites were characterised using various analytical techniques such as Raman, FTIR and UV–Vis spectroscopies, Thermo-Gravimetric Analysis (TGA), X-ray diffraction (XRD) and conductivity measurements, confirming its semi-crystalline nature. The results show shifts in the Raman, XRD and FTIR spectral features associated with the Pani composites, indicating that a matrix of metal oxide and/or graphite had formed in the polymer. Higher electrical conductivity was observed for the Pani/Gr (5.58 S cm−1) and Pani/Gr/MoO2 (9.87 S cm−1) composites compared to pure Pani (1.25 S cm−1). The homogenous growth of Pani chains on the graphite and MoO2 network were clearly observed by Scanning Electron Microscopy (SEM) and Energy Dispersive Analysis by X-ray (EDAX). A larger surface area and greater porosity were achieved in the Pani/MoO2, Pani/Gr/MoO2 and Pani/Gr samples, while a more compact structure was obtained for the Pani sample. These findings support that the idea that the polymer/graphite composites would be more useful for electrochemical charge transport, supercapacitance and energy storage applications compared to those using the pure polymer alone.

This article describes the electroplating of Zn Ni alloy from a modified deep eutectic solvent (DES), a mixture of choline chloride (ChCl) and ethylene glycol (EG) commonly known by its commercial name Ethaline. In this study the Ethaline was modified with propylene carbonate (PC) to decrease the solution viscosity. Boric acid was also used as an additive to improve surface finish and adhesion. The modifications were shown to increase the reduction rate of metal ions through improved mass transport and also to improve the quality of finish (morphology and interfacial adhesion) of the coating. We demonstrate that it is possible to produce dense, thick and adherent coatings of a γ-phase Zn Ni alloy with 81–85% Zn on mild steel substrates using either potentiostatic deposition or controlled current pulse-plating techniques. Mild steel is a typical substrate for a sacrificial anti-corrosion coating used in many applications where the alloy serves to protect the steel from corrosion in harsh environments.

The generation and accumulation of environmental pollutant of industrial contaminations gave it a big challenge to develop many removal strategies of pollution. Textile dyes as dispersive blue 26 dye affected by several decolorization parameters like as temperature, initial pH and initial concentrations of dye. These variables parameter were studied on ZnO-dye suspension solution in dark and photoreaction conditions. In dark reaction, with using thermodynamic and kinetic parameters such as ΔH°, ΔS°, ΔG° and Ea, the type of adsorption was determined and found as a physical adsorption, exothermic and fast reaction. Moreover, the results demonstrated that the photoreaction process under UV-light-A would elevated the rate of reaction, percentage of decolorization and accelerated the half-time of decolorization reaction in 50 ppm of dye. The photoreaction of decolorization of this dye acts as pseudo first order kinetics with endothermic, less random less, non spontenous and fast reaction.

The effects of additives on the electrodeposition of Zn Sn alloy from aqueous electrolyte have been the subject of considerable interest in the literature; however, to date there has been little consideration of their effects on alloy electrodeposition from Deep Eutectic Solvents (DESs). This work will show, for the first time, the effects of boric acid, ammonium chloride and nicotinic acid on the electrodeposition of Zn Sn alloys on copper from a DES consisting of a stoichiometric 1:2 mix of choline chloride and ethylene glycol (Ethaline 200). Cyclic voltammetry has been used to study the electrochemical properties of the Zn Sn electrolyte, and the resultant surface morphologies, composition and roughness of the Zn Sn coating were revealed via SEM/EDX and AFM, demonstrating that boric acid and nicotinic acid function as very effective brighteners, producing highly uniform and smooth Zn Sn deposits. It was found that these additives strongly affect the morphology, composition, and roughness of the Zn Sn coating. XRD was also used to examine the crystal structure of Zn Sn coatings, where it was found that the phase composition of the deposits depends on the additive(s) used. In addition, corrosion of the Zn Sn alloy in salty media was measured using the Tafel method.

Physical properties of pure DESs and DESs mixed with different amounts of water were investigated by different techniques, including, rotational viscometer, Quartz Crystal Microbalance (QCM) and conductivity meter. In order to study heterogeneity of those liquids in nature. Analysis of these data showed some characteristics of heterogeneity, the extent of which depends on the number of hydrogen bond donors in the pure DES.

An economic and sensitive method was developed to measure pyridoxine hydrochloride (vitamin B6) in pharmaceutical formation as an ion pair, as depending on the charge transfer reaction with SDS as a surfactant and a suitable analytical reagent (chlorazol black). The parameters that gave optimum reaction conditions, such as the concentrations of chlorozal black, SDS, pH, equilibration temperature, time and effect of salting were studied to obtain a linear calibration curve where the linearity range was found to lie between 1.22 × 10-3to 34 × 10-2mM, and the detection limit (LOD) 2.56 × 10-4mM. The method was applied successfully to determine vitamin B6 concentrations in various pharmaceutical samples.

A modern and easy procedure performed using the turbidity method for the pre-concentration and estimating of Cu (II) in pharmaceutical samples. The limited solubility complex formed by the reaction of copper ions with cysteine and SDS as the surfactant. The copper content measured using the turbidity method. The effect of chemical and physical parameters including grouping of the ligand, SDS, pH, equilibration temperature and time and effect of salting are studied. The analytical qualities of the technique have been determined, which includes linear range (the range was between 0.158 -47.625µgmL 1), the coefficient of turbidity (k=13.21), limit of detection (LOD=0.1767 µg ml 1nd LOQ=0.5355 µg mL 1).All values are calculated using statistical programs, but the detection limit for Cu(II) ions based on eight times the standard deviation of the blanks (N:8) characterized as 3Sb/m (where Sb is the standard deviation of the blank and m is the slope of the calibration curve) is 0.0096µg mL-1 (3s). The method employed successfully for the determination of Cu2+ in different local pharmaceutical formations.

The concentrations of Ni, Zn, and Cd were examined in forty urine samples. The samples were collected from workers living in Iraq and having different occupations and of different ages. The samples were digested and subsequently assayed via the F-AAS technique. The average concentrations of the Ni, Zn, and Cd were 0.0010 to 0.0543ppm, 0.2923 to 1.1485ppm, and 0.0014 to 0.0487ppm, respectively. The concentrations of Cd and Ni in the urine samples were the lowest. It was found that the concentration of Zn in the urine of people who work in oil refineries was higher than for people working in other vocations. The data were treatment using t-test; F-test and ANOVA test to know the different between the results and the quoted values that published in literature survey.