To determine urea accurately in clinical samples, food samples, dairy products, and agricultural ... more To determine urea accurately in clinical samples, food samples, dairy products, and agricultural samples, a new analytical method is required, and non-enzymatic methods are preferred due to their low cost and ease of use. In this study, bitter gourd peel biomass waste is utilized to modify and structurally transform nickel oxide (NiO) nanostructures during the low-temperature aqueous chemical growth method. As a result of the high concentration of phytochemicals, the surface was highly sensitive to urea oxidation under alkaline conditions of 0.1 M NaOH. We investigated the structure and shape of NiO nanostructures using powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). In spite of their flake-like morphology and excellent crystal quality, NiO nanostructures exhibited cubic phases. An investigation of the effects of bitter gourd juice demonstrated that a large volume of juice produced thin flakes measuring 100 to 200 nanometers in diameter. We are able to detect ...
Cholesterol is considered an essential component in animal bodies that plays a vital role in horm... more Cholesterol is considered an essential component in animal bodies that plays a vital role in hormone production and creating vitamin D. The elevated blood cholesterol level increases the possibility of heart disease. Consequently, the clinical diagnosis of cholesterol concentration is critical for human health care. The electrochemical sensor is one of the leading techniques for detecting cholesterol in biological fluids with high accuracy. Therefore, this review included comparative insights into the enzymatic and non-enzymatic techniques for electrochemical sensing. We discussed the recent progress in the electrochemical determination of cholesterol via various materials, e.g., metal composites, carbonaceous materials, ionic liquid crystals, and polymers. We explained electrochemical sensing techniques like amperometric, potentiometric, conductometric, and impedimetric methods. Furthermore, various enzyme-immobilization approaches were reported, like surface binding and encapsulation. The synergistic effect between the electrode surface and enzymes was demonstrated to clarify the detection mechanism. The review article summarized the outcome detection limits and linear range of detection for various surfaces for enzymatic and non-enzymatic electrochemical techniques within the last twenty years.
The fabrication of enzyme‐free glucose sensors is highly demanded for the biological, clinical, a... more The fabrication of enzyme‐free glucose sensors is highly demanded for the biological, clinical, and food applications. In this study, we have developed a green method for tuning the surface properties of nickel‐cobalt bimetallic oxide (NiCo2O4) by adding mustard (Brassica Campestris) leaves extract during hydrothermal growth. The mustard (Brassica Campestris) leaves extract is rich with a variety of phytochemicals, which can easily tune the surface properties of NiCo2O4 nanostructures, thereby paving the way toward the development of sensitive and selective non‐enzymatic glucose sensors. The effect of various amounts of mustard (Brassica Campestris) leaves extract (0–20 ml) was also studied to find out the optimal conditions for growing surface‐modified NiCo2O4 nanostructures. The morphology and crystalline structure of the nanomaterials were studied by scanning electron microscopy (SEM) and powder X‐ray diffraction (XRD) techniques, respectively. The presence of an increasing quant...
Nickel-based surfaces have received significant attention as an efficient substrate for electroox... more Nickel-based surfaces have received significant attention as an efficient substrate for electrooxidation. This work studied doped nickel surfaces with Cu atoms to enhance the CO-Tolerance. A comparative study was performed for CO adsorption upon different cleavage facets of pristine and Cu-doped nickel surfaces, whereas the adsorption energy, charge transfer, and density of state for CO were estimated using GGA-RPBE calculation method. Several adsorption probabilities were considered, and the change in adsorption energy and bond lengths were used to explain the CO adsorption mechanism. Otherwise, the density of state was employed to study the 3σ and 1π orbital to demonstrate the adsorption of CO onto the different facets. According to our analysis, the Cu-doped nickel surface showed higher CO tolerance than the pristine nickel surface. Whereas the calculated CO adsorption energies of Cu-doped surfaces have more positive values than the non-doped counterparts. The catalytic ability of pristine and Cu-doped Ni(111) was studied to evaluate the ability of surface poisoning resistance. Thus, oxidation of CO to CO2 was studied using the Eley-Rideal mechanism upon the pristine and Cu-doped surfaces of Ni(100) where the rate-determining step for CO oxidation upon the reported surfaces was estimated as CO + O2* → CO2* + O* by an energy barrier of 1.05 and 0.9 eV for pristine, and Cu-doped Ni (100).
The electrochemical performance of NiCo2O4 with urea precursors was evaluated in order to develop... more The electrochemical performance of NiCo2O4 with urea precursors was evaluated in order to develop a non-enzymatic urea sensor. In this study, NiCo2O4 nanostructures were synthesized hydrothermally at different concentrations of urea and characterized using scanning electron microscopy and X-ray diffraction. Nanostructures of NiCo2O4 exhibit a nanorod-like morphology and a cubic phase crystal structure. Urea can be detected with high sensitivity through NiCo2O4 nanostructures driven by urea precursors under alkaline conditions. A low limit of detection of 0.05 and an analytical range of 0.1 mM to 10 mM urea are provided. The concentration of 006 mM was determined by cyclic voltammetry. Chronoamperometry was used to determine the linear range in the range of 0.1 mM to 8 mM. Several analytical parameters were assessed, including selectivity, stability, and repeatability. NiCo2O4 nanostructures can also be used to detect urea in various biological samples in a practical manner.
A new nano-coating of chitosan nanoparticles/polyvinylpyrrolidone/cobalt oxide nanoparticles (CSN... more A new nano-coating of chitosan nanoparticles/polyvinylpyrrolidone/cobalt oxide nanoparticles (CSNPs/PVP/CoONPs) was performed in this work. The newly designed nano-coating comprises a copolymer and inorganic matrices. This nano-coating was used to cover the Ti-6Al-4V alloy surface as a newly designed dental alloy, and then its corrosion properties were studied through different electrochemical techniques. The results reveal that this novel coating improved the corrosion resistance of the Ti-6Al-4V alloy in artificial saliva solution by reaching 17.7 MΩ cm2. The new fabricated biocompatible coating (CSNPs/PVP/CoONPs) greatly enhanced the electrochemical corrosion resistance by giving a high protection efficiency of 90.87% and a low hydrogen evolution rate in artificial saliva solution at 37 °C. The observed results were confirmed by scanning electron microscopy (SEM), Vickers microhardness testing, coating thickness tests, high-resolution transmission electron microscopy (HRTEM), and...
Pd (II) complex was prepared from the interaction with Schiff base based on the condensation amox... more Pd (II) complex was prepared from the interaction with Schiff base based on the condensation amoxicillin trihydrate drug and 4‐N,N‐dimethylaminobenzaldehyde. The complex was prepared on the nanoscale that was investigated using transmission electron microscopy (TEM). The chemical structure of the synthesized Schiff base and its Pd (II) chelate was proved through several techniques. Assays using MTT and lactate dehydrogenase verified the Pd (II) complex ability to inhibit human prostate cancer cells (PC3). According to the findings, the inhibition of PC3 cell growth was directly proportional to the dose of Pd (II) complex. Its highest IC50 value was attained after 48 h of incubation reached to 22.6 μg/mL. As a measure of DNA damage in PC3 cells, this IC50 value demonstrated a significant increase in early and late apoptotic cells with an intense comet nucleus. Given that the concentration of reactive oxygen species (ROS) in treated PC3 cells was much higher than in control ones. Thes...
In this work, the IN738 superalloy used previously in gas turbines was recycled and used as a wor... more In this work, the IN738 superalloy used previously in gas turbines was recycled and used as a working electrode for electrooxidation of different fuels, namely, ethylene glycol, ethanol, and urea. The electrocatalytic efficiency of the electrode was studied by cyclic voltammetry, chronoamperometry, and electrochemical impedance. Several kinetics parameters like diffusion coefficient, Tafel slope, rate constant, and activation energy were calculated. The modified electrode was characterized as received using XRD, SEM, and EDAX to elucidate the crystal structure and surface morphology before and after electrochemical oxidation. The anodic current densities of electrochemical oxidation of ethanol, ethylene glycol, and urea were 29, 17, and 12 mA.cm-2, respectively, in a solution of 1.0 KOH at a potential 0.6 V (vs. Ag/AgCl). The kinetic parameters like diffusion coefficients for ethanol, ethylene glycol, and urea were equaled to 1.5 ×10-6, 1.038×10-6, and 0.64×10-6 cm2 s-1. The charge ...
A modified electrode with conducting polymer (Polyaniline) and NiO nanoflowers was prepared to de... more A modified electrode with conducting polymer (Polyaniline) and NiO nanoflowers was prepared to detect nitrite ions in drinking water. A simple method was used to prepare the NiO nanoflower (NiOnF). Several techniques characterized the as-prepared NiOnF to determine the chemical structure and surface morphology of the NiO, such as XRD, XPS, FT-IR, and TGA. The activity of the electrode toward nitrite sensing was investigated over a wide range of pH (i.e., 2 to 10). The amperometry method was used to determine the linear detection range and limit. Accordingly, the modified electrode GC/PANI/NiOnf showed a linear range of detection at 0.1–1 µM and 1–500 µM. At the same time, the limit of detection (LOD) was 9.7 and 64 nM for low and high concentrations, respectively. Furthermore, the kinetic characteristics of nitrite, such as diffusion and transport coefficients, were investigated in various media. Moreover, the charge transfer resistance was utilized for nitrite electrooxidation in d...
To determine urea accurately in clinical samples, food samples, dairy products, and agricultural ... more To determine urea accurately in clinical samples, food samples, dairy products, and agricultural samples, a new analytical method is required, and non-enzymatic methods are preferred due to their low cost and ease of use. In this study, bitter gourd peel biomass waste is utilized to modify and structurally transform nickel oxide (NiO) nanostructures during the low-temperature aqueous chemical growth method. As a result of the high concentration of phytochemicals, the surface was highly sensitive to urea oxidation under alkaline conditions of 0.1 M NaOH. We investigated the structure and shape of NiO nanostructures using powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). In spite of their flake-like morphology and excellent crystal quality, NiO nanostructures exhibited cubic phases. An investigation of the effects of bitter gourd juice demonstrated that a large volume of juice produced thin flakes measuring 100 to 200 nanometers in diameter. We are able to detect ...
Cholesterol is considered an essential component in animal bodies that plays a vital role in horm... more Cholesterol is considered an essential component in animal bodies that plays a vital role in hormone production and creating vitamin D. The elevated blood cholesterol level increases the possibility of heart disease. Consequently, the clinical diagnosis of cholesterol concentration is critical for human health care. The electrochemical sensor is one of the leading techniques for detecting cholesterol in biological fluids with high accuracy. Therefore, this review included comparative insights into the enzymatic and non-enzymatic techniques for electrochemical sensing. We discussed the recent progress in the electrochemical determination of cholesterol via various materials, e.g., metal composites, carbonaceous materials, ionic liquid crystals, and polymers. We explained electrochemical sensing techniques like amperometric, potentiometric, conductometric, and impedimetric methods. Furthermore, various enzyme-immobilization approaches were reported, like surface binding and encapsulation. The synergistic effect between the electrode surface and enzymes was demonstrated to clarify the detection mechanism. The review article summarized the outcome detection limits and linear range of detection for various surfaces for enzymatic and non-enzymatic electrochemical techniques within the last twenty years.
The fabrication of enzyme‐free glucose sensors is highly demanded for the biological, clinical, a... more The fabrication of enzyme‐free glucose sensors is highly demanded for the biological, clinical, and food applications. In this study, we have developed a green method for tuning the surface properties of nickel‐cobalt bimetallic oxide (NiCo2O4) by adding mustard (Brassica Campestris) leaves extract during hydrothermal growth. The mustard (Brassica Campestris) leaves extract is rich with a variety of phytochemicals, which can easily tune the surface properties of NiCo2O4 nanostructures, thereby paving the way toward the development of sensitive and selective non‐enzymatic glucose sensors. The effect of various amounts of mustard (Brassica Campestris) leaves extract (0–20 ml) was also studied to find out the optimal conditions for growing surface‐modified NiCo2O4 nanostructures. The morphology and crystalline structure of the nanomaterials were studied by scanning electron microscopy (SEM) and powder X‐ray diffraction (XRD) techniques, respectively. The presence of an increasing quant...
Nickel-based surfaces have received significant attention as an efficient substrate for electroox... more Nickel-based surfaces have received significant attention as an efficient substrate for electrooxidation. This work studied doped nickel surfaces with Cu atoms to enhance the CO-Tolerance. A comparative study was performed for CO adsorption upon different cleavage facets of pristine and Cu-doped nickel surfaces, whereas the adsorption energy, charge transfer, and density of state for CO were estimated using GGA-RPBE calculation method. Several adsorption probabilities were considered, and the change in adsorption energy and bond lengths were used to explain the CO adsorption mechanism. Otherwise, the density of state was employed to study the 3σ and 1π orbital to demonstrate the adsorption of CO onto the different facets. According to our analysis, the Cu-doped nickel surface showed higher CO tolerance than the pristine nickel surface. Whereas the calculated CO adsorption energies of Cu-doped surfaces have more positive values than the non-doped counterparts. The catalytic ability of pristine and Cu-doped Ni(111) was studied to evaluate the ability of surface poisoning resistance. Thus, oxidation of CO to CO2 was studied using the Eley-Rideal mechanism upon the pristine and Cu-doped surfaces of Ni(100) where the rate-determining step for CO oxidation upon the reported surfaces was estimated as CO + O2* → CO2* + O* by an energy barrier of 1.05 and 0.9 eV for pristine, and Cu-doped Ni (100).
The electrochemical performance of NiCo2O4 with urea precursors was evaluated in order to develop... more The electrochemical performance of NiCo2O4 with urea precursors was evaluated in order to develop a non-enzymatic urea sensor. In this study, NiCo2O4 nanostructures were synthesized hydrothermally at different concentrations of urea and characterized using scanning electron microscopy and X-ray diffraction. Nanostructures of NiCo2O4 exhibit a nanorod-like morphology and a cubic phase crystal structure. Urea can be detected with high sensitivity through NiCo2O4 nanostructures driven by urea precursors under alkaline conditions. A low limit of detection of 0.05 and an analytical range of 0.1 mM to 10 mM urea are provided. The concentration of 006 mM was determined by cyclic voltammetry. Chronoamperometry was used to determine the linear range in the range of 0.1 mM to 8 mM. Several analytical parameters were assessed, including selectivity, stability, and repeatability. NiCo2O4 nanostructures can also be used to detect urea in various biological samples in a practical manner.
A new nano-coating of chitosan nanoparticles/polyvinylpyrrolidone/cobalt oxide nanoparticles (CSN... more A new nano-coating of chitosan nanoparticles/polyvinylpyrrolidone/cobalt oxide nanoparticles (CSNPs/PVP/CoONPs) was performed in this work. The newly designed nano-coating comprises a copolymer and inorganic matrices. This nano-coating was used to cover the Ti-6Al-4V alloy surface as a newly designed dental alloy, and then its corrosion properties were studied through different electrochemical techniques. The results reveal that this novel coating improved the corrosion resistance of the Ti-6Al-4V alloy in artificial saliva solution by reaching 17.7 MΩ cm2. The new fabricated biocompatible coating (CSNPs/PVP/CoONPs) greatly enhanced the electrochemical corrosion resistance by giving a high protection efficiency of 90.87% and a low hydrogen evolution rate in artificial saliva solution at 37 °C. The observed results were confirmed by scanning electron microscopy (SEM), Vickers microhardness testing, coating thickness tests, high-resolution transmission electron microscopy (HRTEM), and...
Pd (II) complex was prepared from the interaction with Schiff base based on the condensation amox... more Pd (II) complex was prepared from the interaction with Schiff base based on the condensation amoxicillin trihydrate drug and 4‐N,N‐dimethylaminobenzaldehyde. The complex was prepared on the nanoscale that was investigated using transmission electron microscopy (TEM). The chemical structure of the synthesized Schiff base and its Pd (II) chelate was proved through several techniques. Assays using MTT and lactate dehydrogenase verified the Pd (II) complex ability to inhibit human prostate cancer cells (PC3). According to the findings, the inhibition of PC3 cell growth was directly proportional to the dose of Pd (II) complex. Its highest IC50 value was attained after 48 h of incubation reached to 22.6 μg/mL. As a measure of DNA damage in PC3 cells, this IC50 value demonstrated a significant increase in early and late apoptotic cells with an intense comet nucleus. Given that the concentration of reactive oxygen species (ROS) in treated PC3 cells was much higher than in control ones. Thes...
In this work, the IN738 superalloy used previously in gas turbines was recycled and used as a wor... more In this work, the IN738 superalloy used previously in gas turbines was recycled and used as a working electrode for electrooxidation of different fuels, namely, ethylene glycol, ethanol, and urea. The electrocatalytic efficiency of the electrode was studied by cyclic voltammetry, chronoamperometry, and electrochemical impedance. Several kinetics parameters like diffusion coefficient, Tafel slope, rate constant, and activation energy were calculated. The modified electrode was characterized as received using XRD, SEM, and EDAX to elucidate the crystal structure and surface morphology before and after electrochemical oxidation. The anodic current densities of electrochemical oxidation of ethanol, ethylene glycol, and urea were 29, 17, and 12 mA.cm-2, respectively, in a solution of 1.0 KOH at a potential 0.6 V (vs. Ag/AgCl). The kinetic parameters like diffusion coefficients for ethanol, ethylene glycol, and urea were equaled to 1.5 ×10-6, 1.038×10-6, and 0.64×10-6 cm2 s-1. The charge ...
A modified electrode with conducting polymer (Polyaniline) and NiO nanoflowers was prepared to de... more A modified electrode with conducting polymer (Polyaniline) and NiO nanoflowers was prepared to detect nitrite ions in drinking water. A simple method was used to prepare the NiO nanoflower (NiOnF). Several techniques characterized the as-prepared NiOnF to determine the chemical structure and surface morphology of the NiO, such as XRD, XPS, FT-IR, and TGA. The activity of the electrode toward nitrite sensing was investigated over a wide range of pH (i.e., 2 to 10). The amperometry method was used to determine the linear detection range and limit. Accordingly, the modified electrode GC/PANI/NiOnf showed a linear range of detection at 0.1–1 µM and 1–500 µM. At the same time, the limit of detection (LOD) was 9.7 and 64 nM for low and high concentrations, respectively. Furthermore, the kinetic characteristics of nitrite, such as diffusion and transport coefficients, were investigated in various media. Moreover, the charge transfer resistance was utilized for nitrite electrooxidation in d...
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