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The need of quick testing of nicotine (NIC) is vital because of its hurtful impacts on human. NIC detection has been successfully developed using a novel sensitive simple electrochemical sensor. The sensor system is based on modifying a carbon paste electrode (CPE) using Ni and Cu nanoparticles to develop the new nickel/copper nanoparticle–modified carbon paste electrode (NCNMCPE) with low-cost and simple procedure. The sensor showed excellent electrocatalytic activity for NIC oxidation in phosphate buffer solution (pH 7.0) at a lower voltage of 1.3 V, with a linear response from 6.0 to 1000.0 µM. The detection limit (LOD) was estimated to be 0.14 nM. The sensing performance of the NCNMCPE for the electro-oxidation of NIC was examined utilizing cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). Scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX) techniques were used to achieve surface characteristics.

Zn-based alloys have found increasing interest as orthopedic biodegradable implantable materials, hence it was the aim of this work to investigate the microstructure and corrosion behavior of Zn–0.5Al–xMg cast alloys with different Mg additions in simulated body fluid (SBF). The cast samples were prepared using a simple stir casting method and the molten alloys were poured in a cast iron mold. The SEM results showed that adding Mg greatly influenced the microstructure of the Zn-based alloys where the degree of fineness of the microstructure increased with a rise in the Mg content. Moreover, polarization measurements revealed that the Zn–0.5Al–0.6Mg alloy attained the lowest degradation rate of 0.33 mm/year as compared to the other investigated alloys which complies the requirements of ideal corrosion rates for biodegradable bone implants. This corrosion rate helps the implantable metal alloy to last in the body until healing of the bone tissue proceeds. The fine structure and uniform distribution of Aluminum oxide and MgZn2 intermetallic phases along the grain boundaries were most likely the main factors in the superior corrosion stability of the Zn–0.5Al–0.6Mg alloy in SBF. However, higher concentrations of Mg (1 wt%) lowered the corrosion resistance of the Zn–Al–Mg alloy which was attributed to the accelerated galvanic corrosion between Zn and Mg2 Zn11 phases and the inhomogeneous distribution of corrosion products on the alloy surface due to the increased grain size and the coarse structure of the Zn alloy.

Green synthesis of zero-valent copper nanoparticles successfully performed using Ficus benjamina leaves. The novel adsorbent Ficus nano-zero-valent copper (FB-nZVCu) characterized by utilizing scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FT-IR). The size of these nanoparticles typically ranges from 16 to 18 nm. This adsorbent investigated for removal of D-blue 60 from textile wastewater. The impact of different operating parameters, including pH, adsorbent dose, stirring rate, time, and initial dye concentration, had been tested, and optimum conditions were selected to gauge the optimum dye removal performance of the adsorbent. The maximum removal efficiency of D-blue 60 reached 87% under the following proper conditions: adsorbent dose 0.3 g L−1, time 30 min, and pH 8. The Langmuir isotherm was found to be the most appropriate system for the adsorption process (R2 = 0.9994) and (qmax = 30.03 mg g−1). The pseudo-second-order model defined the adsorption. From the data obtained and the fruitful discussion, it detected that the FB-nZVCu green adsorbent strongly recommended as a hopeful substance for removing D-blue 60 from both synthetic and actual waste samples.Highlights Green synthesis of eco-friendly FB-nZVCu nanoparticles utilizing low-cost material Ficus benjamina leaves. The FB-nZVCu nanoparticles are efficient nano-adsorptive agents for removing D-blue 60 from wastewater under optimum conditions. The Langmuir isotherm and PSO kinetics model provided a good fit to the adsorption data.

Herein, nanocomposite coatings consisting of chitosan (CSNPs) and cobalt nanoparticles (CoNPs) were deposited on bare 316L stainless steel alloy (316L SS) as a bone implant. Scanning electron microscope (SEM) and energy dispersive X-ray (EDX) were applied to characterize the morphological and chemical composition of the tested nanocoatings. In-vitro degradation and hydrogen evolution behaviour of the coated samples were examined by means of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques, in Hank's solution containing of 1 × 10−3 M calcium hydrogen phosphate drug at pH 7.4 and temperature 37 °C. This drug used as an inhibitor for protecting the alloy surface from the corrosive medium and minimized the hydrogen evolution rate. Results showed that the di-phasic coating (CoNPs-CSNPs) gave the highest electrochemical corrosion resistance with the lowest hydrogen evolution rate in comparison to the monophasic coatings (CS-NPs & Co-NPs). These corrosion results suggested that a CoNPs-CSNPs nanocomposite coating on 316L SS was effective for renewable or functional implants.

Green synthesis approach was successful used extract was successful in preparing bimetallic zero-valent Iron/Copper nanoparticles [FB-nZVFe/Cu]. Scanning Electron Microscope [SEM], Fourier Transform Infrared Spectroscopy [FTIR], and Dispersive X-ray Spectroscopy [EDX] showing the synthesizing of FB-nZVFe/Cu. The removal efficiency of Caffeine [5 mg L−1] reached 86% under the conditions [0.2 g L−1, 45 min, and pH 5]. The adsorption data are more appropriate by the Langmuir model [R2 = 0.9987] with qmax = 34.34 mg g−1. Kinetic results showed that Caffeine uptake is following pseudo-second-order. Langmuir and pseudo-second-order are more appropriate in linear and non-linear models. Overall, FB-Fe/Cu is a committed green substance for removal Caffeine from aqueous solutions. Functional parameters affect investigated using the Linear regression analysis, we found them to account for over 98% of the variables affecting the removal procedure.

The aim of this research is for decreasing contaminants using alginate beads with activated carbon entrapped (AG-AC) by adsorption. Different sunset yellow FCF concentrations were prepared in the laboratory. The effect of the different parameters was studied (pH, contact time, adsorbent dose, stirring rate, and concentrations) on the removal processes. The results were analyzed according to the Langmuir, Temkin, Freundlich, and Dubinin-Radushkevich adsorption isotherms. The removal efficiency is more appropriate by the Langmuir isotherm. Sunset yellow FCF (10 ppm) percent removal efficiency is (86%) at pH 3 and 10 g\L of the adsorbent dose for 30 min with a fixed stirring rate (100 rpm). The effect of different operating parameters was investigated using Linear regression analysis which occupies more than 97 % of the total of the variables affecting the removal process. Finally, I recommend using this technology for Removal of Sunset Yellow FCF.

Green synthesis of nanoparticles is an eco-friendly treatment technique. Bimetallic nano zero-valent Fe/Cu was successfully prepared by green synthesis by Ficus Benjamina leaves (FB-ZVI/Cu). The nanoscale FB-ZVI/Cu was characterized by scanning electron microscope, Fourier transform infrared spectroscopy, and dispersive X-ray spectroscopy. The characterization revealed that synthesis and presence of iron–copper nanoparticles and biomolecules which could help in capping the bimetallic nanoparticles. Subsequently, nanoscale zero-valent Fe/Cu particles were used to remove carbamazepine from the aqueous medium under varying experimental conditions, including pH, initial carbamazepine concentration, Fe/CuNPs dose, stirring rate, and contact time. The removal efficiency of carbamazepine reached 95% under the condition of dose 0.4 g L−1, time 20 min, and pH 5. The results were analyzed according to the Freundlich and Langmuir adsorption isotherms. The adsorption data are more appropriate by the Langmuir adsorption model (R2 = 0.998) with qmax = 26.15 mg g−1. Overall, FB-nZVFe/Cu is a promising green substance to remove carbamazepine from aqueous solutions. The effect of different operating parameters was investigated using linear regression analysis, they were found to account for more than 97% of the variables affecting the removal process.

The corrosion behaviour and characterisation properties of a novel Ni–P coating on anodised aluminium alloys were inspected by utilising a salt spray technique and a polarisation system in artifici...

Electroless Ni-B and Ni-B-Sn ternary alloy nano-coatings were deposited successfully on aluminum substrate from alkaline borohydride bath. The coatings were analyzed using scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS). X-ray diffraction (XRD) was performed to investigate the phase structure characterization of the coated samples; the crystal size was calculated using Scherrer's equation. The properties of Ni-B-Sn coatings such as hardness and wear resistance were assessed and contrasted with that of Ni-B coating. Moreover, the quality and electrochemical performance of these coatings has been investigated in 3.5% NaCl solution using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The influence of heat treatment on the performance of coated samples was studied at 400 °C for 1 h. The results revealed that, the addition of tin particle and heat treatment provides satisfactory enhancement in hardness and wear resistance of the coatings. The electrochemical corrosion performance was highly improved by the integration of tin to Ni-B coating but heat treatment reduces the anticorrosion ability due to the disappearance of the amorphous characteristics of the as-deposited coating.

The corrosion behavior of the hard anodizing coating layer, formed on Aluminum alloys in sulphuric acid electrolyte containing sodium lignin sulphonate, was investigated by using salt spray procedure and Potentiodynamic polarization technique, in 3.5% sodium chloride solution. The anodic process was performed on different groups of Aluminum alloys as Al2014, Al6061and Al7075, which are used in military industries. The results showed that the corrosion resistance and the anodized coating layer are influenced by the type of the alloy and the anodizing conditions such as current density, acid concentration and time of duration. Moreover, changes in film thickness, anodic coating weight and hardness of Aluminum alloys have been studied and the obtained results were compared and analyzed. Adsorption of sodium lignin sulphonate on oxide surface has been confirmed by Fourier transform infrared spectroscopy (FTIR). The phenolic and carboxylic groups in lignin inhibitor are responsible for forming a complex on the metal oxide surface, that improves the corrosion resistance.

Magnesium and magnesium-zinc-calcium based alloys are so attractive as a biodegradable implant materials. The corrosion behavior of pure Mg (≥99.99% wt.) and three Mg based alloys Mg–xZn–yCa (x = 1,2 and 2.5 wt% & y = 0.6, 0.6 and 1.5 wt%) have been performed in simulated body fluid (SBF) at 37 °C using hydrogen evolution, weight loss, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. Surface morphology and microstructure was studied using scanning electron microscope (SEM), and energy dispersive X- ray spectroscopy (EDX). The addition of Ca and Zn to magnesium alloys has a grain refinement and improving its hardness. The microstructure of the alloys containing primary Mg and eutectic phases (α Mg + Mg2Ca + Ca2Mg6Zn3) mainly dispersed straight to the grain boundaries. The electrochemical tests proved that the Mg–2Zn–0.6Ca alloy has the highest corrosion resistance. Adding Zn improved well the corrosion behavior of the alloy due to the construction of Ca2Mg6Zn3 phase. Whereas adding Ca more than 0.6 wt. % resulted in a decrease of the corrosion behavior owing to the formation of Mg2Ca.

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Zinc and its alloys have been given promising consideration as a new biodegradable implant for use in the human body. Compact and uniform nano hydroxyapatite coatings containing chitosan were successfully deposited onto zinc substrate in an aqueous solution utilizing microwave-assisted process in about 10 min. The quick composite coatings are derived by microwave heating compared with the coatings derived by electrodeposition. The as-deposited coatings formed by electrodeposition synthesis were known as brushite, which was converted to hydroxyapatite after 1 h of immersion (post treated) in 1 M aqueous sodium hydroxide solutions at 100 °C. The incorporation of chitosan (from 0.01–0.05 g/l) into the coating composition results in a smooth and uniform coating structure. SEM, EDS, and an X-ray diffractometer were utilized to analyze coated samples' surfaces to evaluate their surface morphology, chemical composition, and crystalline structures. The in vitro degradation behavior of the composite-coated samples in simulated body fluid at pH 7.4 and 37 °C was evaluated using electrochemical impedance spectroscopy and potentiodynamic polarization. The outcomes showed that microwave-derived coatings provided superior corrosion resistance for zinc implants as compared to electrodeposited coatings. Furthermore, the use of chitosan in hydroxyapatite coatings increased electrochemical corrosion performance. Low chitosan concentrations (0.01–0.03 g/l) exhibit superior anti-corrosion properties than higher concentrations (0.05 g/l). Against Staphylococcus aureus, the coatings demonstrated strong antibacterial efficacy. These corrosion outcomes and the fruitful deposition of a hydroxyapatite/chitosan composite coating on zinc substrate indicate that the coating is efficient for the creation of new composite coatings for either functional implants or regenerative medicine. The resultant coating may be an excellent option for bone implants.

Green synthesis approach using Ficus benjamina leaves extract was successfully used for preparing bimetallic zero-valent iron/copper nanoparticles. The characterization using scanning dispersive X-ray spectroscopy, scanning electron microscopy, and Fourier-transform infrared spectroscopy confirmed the synthesis of bimetallic nanoparticles. The removal efficiency of metformin HCl (MF) concentration (10 mg/L) reached 73% under the (pH 5, dose 0.2 g/L, and time 30 min). Ficus nano-zero-valent Fe/Cu has good durability and stability and possesses excellent reusability for the MF removal even after being reused five times. Langmuir adsorption model is more appropriate with isotherm by the high correlation coefficients (R2 = 0.9991) with qmax = 42.82 mg g−1. The results of adsorption kinetics indicate that MF uptake on Ficus benjamina ZVFe/Cu nanoparticles is following the pseudo-second-order kinetic model. Overall, green Ficus nZVFe/Cu particle is a committed substance to remove MF. Operational parameters effect was more than 97% on the removal process, which was studied using SPSS linear regression analysis. The formation of FB-nZVFe/Cu.

Firstly, the electrochemical behavior of 316L stainless steel alloy (316L SS) as a bone implant has been studied in Hanks’ solution (pH 7.4) at 37 °C without and/or with calcium hydrogen phosphate drug of different concentrations (1 × 10−5–1 × 10−3 M). This drug acts as an inhibitor to protect the surface of the alloy from the surrounding corrosive physiological medium. The results illustrate that 1 × 10−3 M concentration of the drug is the most protective to 316L SS bone implant. Secondly, a novel sensor was developed electrochemically to sense the corrosion behavior of 316L SS in Hanks’ solution containing various concentrations of calcium hydrogen phosphate drug, by sensing the drug concentration in the solution. The sensor was built up from carbon paste modified with chitosan, cellulose acetate phthalate, and silver nanoparticles. The ACCMCPE sensor senses well the drug and exhibits a fast (1.5 s) and a stable response over different concentration ranges (1 × 10−5–1 × 10−3 M) at 50 mV/s. The techniques utilized to explore the corrosion behavior and electrocatalytic activity of the sensor are electrochemical impendence spectroscopy, potentiodynamic polarization, cyclic voltammetry, differential pulse voltammetry, and chronoamperometry. The results was confirmed well with morphological studies.

Magnetic nanosorbents proved to be highly effective in inorganic and organic contaminants removal from aqueous solutions, especially nano zero valent iron (nZVI). The main purpose of this study is to investigate the effect of using nZVI in removing benzene, toluene, ethyl benzene and xylene (BTEX) contaminants from aqueous solutions. The nZVI and the standard BTEX solution were prepared in the laboratory. X-ray diffraction (XRD), UV spectrophotometry, and scanning electron microscopy (SEM) analysis were used for nZVI characterization. The effects of contact time, initial BTEX mixture concentration, adsorbent dose, temperature, and pH on the amount of BTEX absorbed were investigated. The highest removal efficiency of 97% for the BTEX mixture was achieved at a stirring rate of 100 rpm, temperature of 60°C, and pH 7. The minimum effective time for efficient removal was 30 min, while the effective dose for BTEX compounds removal was 0.22 g/L. The Freundlich model was the best fit of experimental data. An artificial neural network (ANN) was used to predict the BTEX removal efficiency. Modeling results showed that ANN with average absolute error of 0.6272% is reliable in describing the adsorption of BTEX onto the iron nanoparticles. It is estimated that the cost of BTEX removal by nZVI under the optimal conditions will be about 3.5 USD per cubic meter.

Glassy carbon (GC) electrode is modified by stepwise manual casting of successive layers of ionic liquid crystals (ILC)/carbon nanotubes (CNTs) and magnetite nanoparticles. The composite [GC/(ILC-CNTs)/Fe 3 O 4 )] is used as a successful NADH biosensor. Molecular interaction of NADH is improved through the conductive and dense structure of ILC/CNTs. Magnetite nanoparticles act as electron-exchange “antennas” resulting in enhanced charge transfer at the interface, selective and sensitive oxidation of NADH. The type of ionic liquid used is key factor for sensor performance. The figures of merit for the proposed NADH sensor are: linear dynamic range of 5–700 μmol L −1 , a sensitivity of 0.0102 μA μmol −1 L, a detection limit of 34.6 nmol L −1 and a limit of quantification of 0.115 μmol L −1 . The sensor showed a stable amperometric response and anti-interfering ability in presence of ascorbic acid, tryptophan, ibuprofen and morphine.

The aim of this study is to decrease ethinylestradiol contaminants using entrapped activated carbon in alginate biopolymer (AG-AC) by adsorption. Different ethinylestradiol concentrations were prepared in the laboratory. The effect of the operating parameter was studied by using different operating parameters (e.g., contact time, pH, concentrations, adsorbent dose and stirring rate). The results were analyzed according to the Freundlich, Langmuir, Temkin and Dubinin–Radushkevich adsorption isotherms. The adsorption data are more appropriate by the Freundlich isotherm. Removal efficiency percentages for ethinylestradiol at pH 3 using dose 10 g/L of the adsorbent for 30 min with a fixed stirring rate at 100 rpm were ~ 84%. The effect of different operating parameters was investigated using linear regression analysis, and they were found to account for more than 99% of the variables affecting the removal process.

A simple and efficient electrochemical sensor is presented for detecting H2O2 in human blood serum based on ionic liquid crystal (ILC), carbon nanotubes (CNTs) and Fe-Ni alloy nanoparticles modified glassy carbon electrode (GC). The sensor is fabricated by drop-casting two successive thin layers of ILC and (CNT-Fe-Ni) mixture over a GC surface; GC/ILC/(CNT-Fe-Ni). The synergism between the composite modifiers leads to excellent electrocatalytic activity toward H2O2 reduction in phosphate buffer solution with a well-identified reduction peak at −380 mV. The H2O2 conversion process is kinetically more favored over the sensor surface with a reduction current value of 178 μA compared to other studied modified electrodes. Amperometry determination of H2O2 in blood serum using the proposed sensor is achieved in a wide concentration range (0.007–1000 μM) and with low detection limit (0.971 nM). Practical application of the GC/ILC/(CNT-Fe-Ni) sensor is effectively assessed in human serum samples with acceptable recoveries, excellent anti-interference ability and long-term stability.

Green chemistry approach has become the eco-friendliest and effective technique by using Ficus Benjamina for preparing bimetallic nanoscale zerovalent Fe/Cu particles and removal of phosphates from the aqueous solutions. Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and dispersive X-ray spectroscopy (EDAX) were used for characterisation. The removal adequacy of phosphates (5 mg L−1) reached to 73% under the condition of 0.3 g L−1, 30 min, and pH 4. The adsorption results are more appropriate by the Langmuir model [R2 = 0.998], with qmax = 17.42 mg g−1. The results of adsorption kinetics indicate that, phosphates uptake on Ficus-nZVFeCu is following the pseudo-second order model. Overall, Benjamina nZVFe/Cu is a committed green substance to remove phosphates. Operating parameters effect was investigated using a SPSS-linear regression analysis and found that more than 97% of the variables have an effect on the removal process.

A sensitive electrochemical sensor was developed by modifying a carbon paste electrode (CPE) with silver nanoparticles (AgNPs)/multi walled carbon nanotube (CNT)/folic acid (FA) for the improved detection of creatinine. The sensor demonstrated high electrocatalytic activity to the oxidation of creatinine in universal buffer solution. Scanning electron microscopy (SEM) and Energy dispersive X-Ray analysis (EDX) were employed for studying the surface morphology. Cyclic voltammetry (CV), differential pulse voltammetry (DPVs), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) were utilized to study the electrocatalytic activity of the sensor. The electrode exhibited a good selectivity, stability and fast response (1.5 s) over a range of concentration (1 × 10−8 to 2 × 10−4 M) for creatinine at pH 7.0 giving a detection limit of 0.008 µM. Real aliquot exploration was done utilizing human urine and serum. The constructed sensor has proved to be very effective in evaluating the creatinine in terms of low detection limit, high sensitivity and reproducibility.