Metallic Copper Nanoparticles Research Articles

The Copper Metal and Magnetite Nanoparticles Conjugated with Salicylic Acid Composite Stimulated Wheat Defense Mechanism and Affected Cellular Components under Heat Stress

Aims: This study aimed to examine the effect of magnetite coating of salicylic acid and Cu metal nanoparticles on yield, cellular contents, and some biochemical constituents of wheat subjected to heat stress. Background: An applied experiment was conducted over two seasons at the Agricultural Experimental Station of Desert Research Center (DRC), which was supervised by the El Wadi El Gadeed Governorate in Egypt. The grains of wheat cultivars Sids1 (tolerant) and Gimmeza7 (sensitive) were treated with copper metal as NPs (Cu NPs) (0.25, 0.50, 0.75, 1.0, and 10 ppm) and magnetite NPs (0.25, 0.50, 0.75, 1.0 and 10 ppm) coated with salicylic acid at 100ppm (Fe NPs+SA). Objective: The objective of this study was to examine wheat tolerance to heat stress and subsequently yield by comparing two wheat cultivars under the same conditions. Method: The chemically formulated nanoparticles were well characterized and applied in two wheat cultivars subjected to heat stress. Results: The results showed that all NPs treatments had a positive impact on all physiological parameters and grain yield. Sids1 surpassed Gemmeiza7 in the quality of wheat grains (essential, nonessential amino acids). However, Gimmeza7 exceeded Sids1 in yield quantity, especially with the application of SA+Fe NPs at 0.50 ppm. These effects were associated with heat tolerance and the best survival in wheat cultivars. There was an increase in glutathione content, antioxidant enzymes (Glutathione -S- Transferase), and/or a decline in malondialdehyde content. Conclusion: Fe NPs+SA (0.5ppm) helped the Gimmeza7 cultivar to mitigate the effects of heat stress through activating growth, glutathione, and glutathione S transferase, enhancing yield quantity in two wheat cultivars (Misr1 and Gimmeza11), and decreasing their MDA content.

Preparation, characterization, and evaluation of an acetylene black polyurethane composite electrode modified with copper nanoparticles for the determination of escitalopram

Escitalopram (ESC) is a widely prescribed antidepressive drug worldwide and must be monitored in biological fluids and environmental samples. Thus the preparation of an acetylene black-polyurethane composite electrode modified with copper metallic nanoparticles by electrodeposition intended for the determination of ESC in synthetic urine and mineral water samples is presented. The surface was further electrochemically pretreated in 0.50 mol/L NaOH in order to obtain a stable mixture of Cu (II) oxides on top of the Cu° nanoparticles. After preconditioning in 0.10 mol/L phosphate buffer pH 7.0, the modified electrode was used in the determination of ESC in the proposed matrixes using CV and DPV, after optimizing experimental parameters. The interaction of the analyte with copper (II) ions promoted a decrease of the Cu(II) reduction peak which was proportional to the ESC concentration in the 0.020–0.10 µmol/L (LOD = (5 ± 1) nmol/L) and 0.040–0.20 µmol/L (LOD = (5.1 ± 0.9) nmol/L) in cyclic voltammetry (CV) and differential pulse voltammetry (DPV) respectively. Interferences from ascorbic acid, uric acid, dopamine and creatinine were evaluated, however the last one present in synthetic urine did not prevented the determination of ESC, as well as the other chemical species naturally present in the mineral water

Numerical study of hybrid binary Al2O3-Cu-H2O nanofluid coating boundary layer flow from an exponentially stretching/shrinking perforated substrate with Cattaneo-Christov heat flux, heat source, suction and multiple slip effects

Modern coating systems are increasingly deploying nanomaterials which offer improved thermal performance. The optimization of these systems can benefit from more elegant fluid dynamic models of the coating process. Inspired by these advancements, the present investigation introduces a novel mathematical model to analyze the boundary layer transport in Al2O3-Cu-H2O hybrid binary nanofluid coating deposition on an exponentially stretching porous substrate (sheet). Lateral mass flux (suction) at the wall is also considered a heat source (generation) for hot spot manufacturing effects. To add further sophistication to the thermal conduction model, a non-Fourier approach is adopted which accurately incorporates thermal relaxation effects i.e. the Cattaneo-Christov heat flux (CCHF) model. The Tiwari-Das volume fraction nanoscale formulation is implemented for different combinations of Alumina (Al2O3) and Copper (Cu) metallic nanoparticles in an aqueous base fluid (H2O). Hydrodynamic wall and thermal slip are also included as they feature in coating processes. The fundamental equations governing mass, momentum, and energy conservation, along with the corresponding conditions at the wall (substrate) and free stream, are made dimensionless through suitable scaling similarity transformations. The resulting nonlinear coupled ordinary differential boundary value problem is subsequently addressed using the efficient MATLAB bvp4c routine. Special cases of the non-Fourier model are validated against published results, and the general model is further confirmed through validation using an Adams-Moulton 2-step predictor-corrector algorithm (AMPC). Furthermore, dual solutions of the generalized model are extracted and visualized. A comprehensive study of the effects of key thermophysical key parameters on momentum and thermal characteristics (velocity, temperature, skin friction and local Nusselt number) is conducted and solutions are visualized graphically. The computations show that higher temperatures are present with intensification in the thermal relaxation parameter (Cattaneo-Christov hyperbolic model parameter), which predicts therefore larger temperatures than the classical Parabolic heat conduction model using Fourier analysis. Effectively, thermal relaxation is responsible for finite heat wave propagation and produces more accurate estimations of heat transfer than the Fourier model. An increase in stretching parameter enhances the skin friction coefficient and elevates the local Nusselt number. As the thermal relaxation parameter increases, the temperature magnitudes corresponding to the first and second solutions are both enhanced as are thermal boundary layer thicknesses. An increase in wall suction induces an escalation in the first solution for velocity whereas it reduces the second solution velocity. Stronger wall suction suppresses temperatures. With increasing thermal slip, the boundary layer is cooled i.e. temperature plummets and thermal boundary layer thickness is decreased. Strong deceleration is induced with greater hydrodynamic (velocity) slip. Both first and second solutions for skin friction are elevated with shrinking whereas they are depressed with stretching. With greater velocity slip both the first and second solutions for skin friction are depleted with greater velocity slip for the shrinking case, whereas they are generally enhanced for the very strong stretching case. The computations offer some new insights into multi-physical thermal fluid dynamics of nanofluid-based coating systems.

Numerically investigating the effect of using nanofluids on the thermal performance and coefficient of performance of a U-tube deep borehole ground source heat pump

In this study, a deep-borehole ground source heat pump was simulated using computational fluid dynamics (CFD) method. The thermal performance and coefficient of performance (COP) of the vertical ground source heat pump simulated with accuracy using CFD for water and 4 different nanofluids as working fluids were investigated. Two nanofluids contained silver and copper metallic nanoparticles and the other two nanofluids contained copper and aluminum oxide nanoparticles. For each of these nanofluids as well as water, the heat exchange rate, total exchanged heat, outlet temperature and COP were calculated and the results were compared together. The results showed that using nanofluids leads to increased exchanged heat. Nanofluids based on aluminum oxide, copper oxide, copper and silver nanoparticles resulted in 4.83, 5.76, 6.9, 7.69 percent increase in total exchanged heat, respectively. In addition to increased exchanged heat, using nanofluids increased the outlet temperature. Also, the results showed that the maximum and minimum increase in COP were 36.5% and 5.2% which were related to using silver and aluminum oxide nanoparticle-based nanofluids, respectively.

Carbon Based Supports for Metal Nanoparticles for Hydrogen Generation Reactions Review

Hydrogen represents a highly promising alternative to fossil fuels due to its exceptional attributes. As the most abundant element in the universe, it holds the potential to revolutionize the energy landscape. When combusted, it generates energy, and the byproduct of this process is simply water, making it an environmentally friendly choice. The adoption of hydrogen as a fuel source has faced constraints primarily related to hydrogen storage technology. Nevertheless, innovative solutions are emerging, such as hydrogen feedstock materials like sodium borohydride (NaBH4), which could offer effective storage capabilities. NaBH4 is particularly noteworthy for containing 10.8% hydrogen by weight and for its ability to release hydrogen gas when reacting with water. Although this release occurs at a relatively slow rate, the introduction of a catalyst could enhance the efficiency of hydrogen production. This comprehensive review endeavors to evaluate the catalytic efficacy of metal nanoparticles when paired with environmentally sustainable catalyst support materials derived from fused carbon microspheres and graphene-like materials. These support materials, sourced from renewable origins, will be intricately combined with a spectrum of metal nanoparticles, encompassing gold, silver, platinum, palladium, and copper nanoparticles. The overarching objective is to investigate how these synergistic combinations can catalyze the expedited release of hydrogen from sodium borohydride, thereby contributing to the streamlined and efficient production of this clean and abundant energy source.

Novel approach for green synthesis of Cu-NPs using Centella asiatica leaf extract, assisted by BiFeO3 nanoparticles for electrochemical glucose- and fructose-sensing applications

This research explored the structural, optical, morphological, and electrochemical properties of the green-synthesized copper metal nanoparticles using Centella asiatica leaf extract and assisted by perovskite-structured bismuth ferrite nanomaterial (Cu/BFO NPs, namely CBO NPs). The structural confirmation of the synthesized CBO NPs was done by X-ray diffraction method, through which the crystallite size was determined to be 52 nm, derived through the Debye–Scherrer equation. The optical absorption band was presented at around 271 and 690 nm. A high-resolution scanning electron microscope revealed the spherical morphology of the synthesized CBO NPs. The electrochemical sugar-sensing activities of CBO NPs and the anti-interference study were performed through cyclic voltammetry and chronoamperometry techniques, respectively. The sensitivity value of the CBO NPs for glucose sugar was found to be 425 μA mM−1 cm−2. The synthesized CBO NPs were suitable for glucose sugar sensor applications.

Synthesis of copper-based nanoparticles confined in a pyridine N-containing COF and their catalytic applications

The main challenge of using non-noble metal copper nanoparticles (Cu NPs) as catalysts is to find or prepare suitable support platforms to anchor Cu NPs, thereby avoiding the aggregation tendency owing to their high surface energy. In this study, a novel pyridine N-containing covalent organic framework (COF) was designed and used as a template for the confined growth of Cu NPs. The prepared imine-connected TAPB-PCBA had abundant one-dimensional ordered channels, moderate specific surface area and good stability. The skeleton structure of TAPB-PCBA contained a large number of evenly distributed pyridine N, which can act as the nucleation site for Cu NPs. The well-defined pore structure confines the growth of Cu NPs and makes them controllable in size. The pores in TAPB-PCBA are completely independent and isolated from each other, minimizing the accumulation of Cu NPs. With the help of these factors, ultrafine Cu/Cu2O composite NPs (2.5 nm) with narrow size distribution anchored inside the cavity of the TAPB-PCBA were successfully prepared. The as-prepared Cu-containing COF, Cu@TAPB-PCBA, showed excellent catalytic capacity for dye degradation and nitrophenol reduction under mild conditions and low catalyst loads, respectively. In addition, Cu@TAPB-PCBA also has a good recyclability, multiple use without significant loss of catalytic activity. We expect this COF-supported growth-confined preparation of metal NPs to further facilitate the design and preparation of non-noble metal NPs@COF composites, replacing noble metals in certain catalytic applications.

Role Of In- Situ Rutin Flavonoid Consisted Myristica Fragrans Silver Nano Particles (MF-Ag-Nps) Against Escherichia Coli and Bacillus Subtilis

Most microbiological growth inhibitors are toxic and chemical solvents are harmful for human health. Copper, silver, and gold metallic nanoparticles have several uses in biotechnology and medicinal research. MF-Ag-NPs(silver nanoparticles)are potent anti-inflammatory, anti-proliferative, and anti-microbial agents. The purpose of this study was to biogenically generate silver nanoparticles by extracting rutin from nutmeg, a seed from the Myristica fragrans plant. In order to create Myristica fragrans MF-Ag-NPs, silver nitrate was dissolved in the extract. The transformation of the colour from dark brown to pale brown confirmed the conversion of Ag+ to Ag°. FTIR, EDX, and SEM were used to describe them. Images from scanning electron microscopy demonstrate the presence of silver nanoparticles between 20 and 300 nm in size. The presence of oxygen and silver, as well as the metal's oxidation state, were confirmed by EDAX analysis. The nanoparticles' distinctive functional groups were discovered using FTIR spectroscopy. The antibacterial activity of Myristica fragrans seed extract was assessed. The extract from the seeds of Myrsitica fragrans exhibited the strongest antibacterial properties. These findings imply that antibacterial MF-Ag-NPs phyto-formulated with nutmeg extracts might be used to treat microbial infections in the future.

Heat transfer analysis of magnetized Cu-Ag-H2O hybrid nanofluid radiative flow over a spinning disk when the exponential heat source and Hall current are substantial: Optimization and sensitivity analysis

The main motive of the instigated mathematical model is to observe the impact of Hall current on the hybrid nanofluid flow over a disk that is rotating. The copper and silver metal nanoparticles have been considered with volume fraction φ1=φ2=0.01(0.01)0.04 and are suspended in water to form the hybrid nanofluid. Diverse characteristics like magnetic field, thermal radiation, and (ESHS) exponential space dependent heat source are incorporated to investigate the nature of the flow. The present mathematical model is initiated with partial derivative equations (PDEs) which are redrafted as ordinary derivative equations (ODEs) with appropriate transformations of similarity. The results are attained through a blend of the Runge-Kutta method, shooting procedure, and the influences of parameters on the flow of nanofluid and hybrid nanofluid are compared and illustrated both as tables and graphs. The present numerical research is unique because by employing a complete quadratic CCD framework using the RSM strategy, the sensitivity and optimization analysis of the heat transmission improvement for the volume fraction, ESHS, and thermal radiation parameters have been performed. The R-squared and adjusted R-Squared are obtained as 100%. The residual graphs and contour diagrams of the same are also shown. The current study establishes that the Hall parameter increases the radial velocity, but it also controls the energy and cross-radial velocity. The rate of heat transmission is increased by thermal radiation even at low levels of ESHS. The rate of heat transmission is more sensitive (0.024670) to the volume fraction of the hybrid nanofluid when ESHS is at an intermediate level. The lowest sensitivity (-1.269967) value towards ESHS is observed For thermal radiation and ESHS parameter values, the heat transmission rate of the mono nanofluid is not as great as that of hybrid nanofluid. The current study finds applications in the generation of hydroelectric power, air cleansing and rotating equipment, healthcare devices, and many other industries.

, , , , , &

Copper (Cu) metal nanoparticles were deposited onto FTO glass using the electrodeposition method. The precursor used was CuSO4×5H2O with Na2SO4 as the inorganic additive. The formation of Cu was characterized using field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). This study investigated the impacts of the electrodeposition method (direct electrodeposition vs. pulse electrodeposition), voltages (‑0.4 V and ‑0.8 V), electrodeposition time (60s to 900s) and pulse cycles (50 cycles to 300 cycles), and FTO etching (fixed to 20s etching) towards the morphology and adhesion of Cu deposited. The grain size and thickness of Cu deposited vary with deposition time and pulse cycles. The voltage of -0.4 V successfully deposits shiny, metallic brown Cu onto FTO glass. Meanwhile, the voltage of -0.8 V gives powdery brown Cu on the surface. In addition, compared to direct electrodeposition (DD), pulse electrodeposition (PD) provides a more compact and homogeneous coverage of Cu onto FTO glass. The tape-test results also indicate that FTO etching by electrolysis reduction can improve the adhesion strength between deposited thin Cu film and the FTO glass. This work demonstrates a facile electrodeposition technique with substrate etching as an effective deposition of Cu metal with the potential for application in a wide range of fields.

Copper Nanoparticles Supported on ZIF-8: Comparison of Cu(II) Reduction Processes and Application as Benzyl Alcohol Oxidation Catalysts.

We report the synthesis of a stable heterogeneous catalyst based on copper metal nanoparticles with oxidized surface supported on ZIF-8 for the oxidation of benzyl alcohol under mild temperature and using air as a sustainable oxygen source as well as for the implementation of the tandem "one-pot" catalytic system allowing the sustainable synthesis of benzylidene malononitrile. The influence of the reduction process applied to form the nanoparticle upon the catalyst texture and its performances was extensively examined. After ZIF-8 impregnation with a copper chloride precursor, the reduction of cupric ions into Cu0 nanoparticles was carried out according to two procedures: (i) by soaking the solid into a solution of NaBH4 and (ii) by submitting it to a flow of gaseous H2 at 340 °C. The in-depth physicochemical characterization and comparison of the resulting two types of Cu/ZIF-8 materials reveal significant differences: the reduction with NaBH4 led to the formation of 16 nm sized Cu0 nanoparticles (NP) mainly localized on the external surface of the ZIF-8 crystals together with ZnO nanocrystallites, while the reduction under H2 flow resulted in Cu0 nanoparticles with a mean size of 22 nm embedded within the bulk of ZIF-8 crystals. More, when NaBH4 was used to reduce cupric ions, ZnO particles were highlighted by high-resolution microcospy imaging. Formation of ZnO impurities was confirmed by the photoluminescence analysis of ZIF-8 after NaBH4 treatment. In contrast, ZnO was not detected on ZIF-8 treated with H2. Both types of Cu0 NPs supported on ZIF-8 were found to be active as catalysts toward the aerobic oxidation of benzyl alcohol under moderate temperature (T < 80 °C) and using air as a sustainable O2 source. Benzaldehyde yield of 66% and selectivity superior to 90% were obtained with the Cu/ZIF-8 catalyst prepared under H2 flow after 24 h under these conditions. The same material could be recycled 5 times without loss of activity, unlike the catalysts synthesized with NaBH4, as a result of the leaching of the surface copper NPs over the consecutive catalytic cycles. Finally, the most stable catalyst was successfully implemented in a tandem "one-pot" catalytic system associating benzyl alcohol oxidation and Knoevenagel condensation to synthesize benzylidene malononitrile.

Hexabranched dendrimers encapsulated metallic copper nanoparticles and their catalytic evaluation for the conversion of para-nitrophenol to para-aminophenol

Two new hexanuclear copper (II) complexes, [Cu6(G2hexpyD)(DMF)24](TFA)12 and [Cu6(G2hexbzaD)(DMF)18](TFA)12, where G2hexpyD and G2hexbzaD are second-generation dendrimers (G = 2) and TFA is trifluoroacetate, have been synthesized. The prepared copper (II) complexes have been fully characterized. Furthermore, to prepare dendrimer encapsulated copper nanoparticles (G2dendrimer-CuNPs), metal ions were chemically reduced by NaBH4 in 2-methoxyethanol, which yielded zero-valent metal particles with a narrow size distribution. The catalytic reduction of para-nitrophenol to para-aminophenol by G2dendrimer-CuNPs was evaluated in the presence of NaBH4. The reduction reaction was completed in 3 min. The reaction progress was monitored by electronic absorption spectroscopy. The rate constant was calculated to be 0.0073 and 0.0079 s−1 for G2hexbzaD-CuNPs and G2hexpyD-CuNPs, respectively. The results revealed that G2dendrimer-CuNPs exhibit high catalytic performance in the conversion of para-nitrophenol to para-aminophenol. Easy separation, low price, high recyclability and great efficiency are the main advantages of G2dendrimer-CuNPs that make them as the suitable catalysts for the catalytic reduction of para-nitrophenol.

Enhanced stability of the nematic phase of 4-pentyl-4ʹ-cyanobiphenyl due to the dispersion of copper nanoparticles

ABSTRACT Embedding of nanoparticles in nematic liquid crystalline materials has received huge attention in recent years. In most of the work, nanoparticles decrease nematic-isotropic transition temperature along with an undesired increase in conductivity. Interestingly, there are few reports where nematic-isotropic transition temperature has increased along with improvement in other relevant properties due to presence of ferroelectric and/or functionalised nanoparticles of small size. Here, we are reporting enhanced nematic-isotropic transition temperature of 4-pentyl-4′-cyanobiphenyl (5CB) due to dispersion of metallic copper nanoparticles (CuNPs). Low concentrations (0.2 and 0.5 weight%) of CuNPs have been dispersed in 5CB to prepare nanocomposites. Thermodynamic results on unaligned samples and dielectric results on planar and homeotropic aligned samples show enhancement of isotropic to nematic transition temperature of 5CB in the presence of CuNPs without any substantial change of conductivity. Optical studies show a marginal decrease in the band gap of the dispersed samples as compared to those of the pure 5CB which validates conductivity results. The relaxation frequency corresponding to the rotation of molecules about their short axes has increased due to the presence of CuNPs in the nematic matrix of 5CB. These observed results are useful for the electro-optical applications as well as for fundamental aspects.

The antimicrobial efficacy of copper, cobalt, zinc and silver nanoparticles: alone and in combination

With the advent of nanotechnology, there has been an extensive interest in the antimicrobial potential of metals. The rapid and widespread development of antimicrobial-resistant and multidrug-resistant bacteria has prompted recent research into developing novel or alternative antimicrobial agents. In this study, the antimicrobial efficacy of metallic copper, cobalt, silver and zinc nanoparticles was assessed against Escherichia coli (NCTC 10538), S. aureus (ATCC 6538) along with three clinical isolates of Staphylococcus epidermidis (A37, A57 and A91) and three clinical isolates of E. coli (Strains 1, 2 and 3) recovered from bone marrow transplant patients and patients with cystitis respectively. Antimicrobial sensitivity assays, including agar diffusion and broth macro-dilution to determine minimum inhibitory and bactericidal concentrations (MIC/MBC) and time-kill/synergy assays, were used to assess the antimicrobial efficacy of the agents. The panel of test microorganisms, including antibiotic-resistant strains, demonstrated a broad range of sensitivity to the metals investigated. MICs of the type culture strains were in the range of 0.625–5.0 mg ml−1. While copper and cobalt exhibited no difference in sensitivity between Gram-positive and Gram-negative microorganisms, silver and zinc showed strain specificity. A significant decrease (p < 0.001) in the bacterial density of E. coli and S. aureus was demonstrated by silver, copper and zinc in as little as two hours. Furthermore, combining metal nanoparticles reduced the time required to achieve a complete kill.

Copper nanoparticles growth on the borophosphate glass surface by bottom-up approach: A catalyst for click reactions

This work proposes synthesizing metal–glass hybrid composites with applications in catalysis. Metallic copper nanoparticles can be self-supported on the surface of borophosphate glasses, an effective substrate for the growth of auto-supported nanoparticles by bottom-up approach. Doped copper glasses were obtained by the melt-quenching method. The temperature required for nanoparticle growth, determined by temperature programmed reduction, is relatively low as 430 °C, and the process can be accomplished in a short time (45 min). In X-ray diffraction analysis, the normalized intensity shows an inverse correlation between the mean glass particle size and the intensity of metallic copper peaks. The glass substrate was characterized by laser-induced breakdown spectroscopy, static laser scattering, and Raman spectroscopy. Scanning electron microscopy was employed to access the morphology, while the crystalline nature of copper was confirmed by X-ray diffraction. The hybrid composites were used as a catalyst on the Click chemistry for 1,2,3-triazoles synthesis under solvent-free conditions.

Copper and Magnetic Activated Carbon Nanocomposites: Application as Recoverable Catalyst for C-S Coupling Reaction.

In this study, activated carbon (AC) was prepared from pistachio nut shell precursor as agricultural by-product. The prepared AC was used to synthesize an efficient nanocomposite via loading of the copper metal and magnetic nanoparticles (Cu-MAC@C4H8SO3H NCs) onto its structure. The structure of the nanocatalyst was characterized by different methods such as FT-IR, TEM, EDS, XRD, VSM, and TGA analysis. The catalytic activity of the prepared composite was tested in a special C-S coupling, namely with the reaction of 2-mercapto-3-phenylquinazolin-4(3H)-one with iodobenzene or bromobenzene. The products of the aryl thioquinazoline derivatives were obtained in good yields and in short reaction times and the products were characterized with 1H, 13C NMR and CHNS analysis. On the other hand, with easy and high recovery of Cu-MAC@C4H8SO3H NCs through magnetic separation, a simple and green method to enhance the efficiency of the nanocatalyst has been provided. The nanocatalyst was reused in the next reaction in up to five cycles without obvious activity decrease.

The role of sulphur in the early production of copper red stained glass

Little is known about the production of ruby red copper stained glasses from the Medieval and Renaissance periods apart from the fact that the colour is due to the presence of small metallic copper nanoparticles and that tin, the most common reducing agent used in copper red glass production since the 19th century, is not present. In fact, very few workshops in Europe were able to make red glass in historical times, and they kept it secret, so very little is known about how it was obtained. These workshops exported the red glass throughout Europe. Recently, the presence of copper sulphide particles and the data obtained in the replication red glass following historical recipes suggested that sulphur might be the key ingredient in this process.Here, a collection of historical red glasses from these periods has been analysed using a combination of microanalytical techniques; Electron Microprobe (EM) and Field Emission and Scanning Electron Microscopy (FESEM) to verify the chemical composition and nanostructure of the glasses, Synchrotron radiation micro-X-Ray Diffraction (micro-XRD) to establish the nature of the nanocrystalline precipitates, and S, Cu and Fe K-edge micro-X-Ray Absorption Spectroscopy (micro-XAS) to determine the speciation. The data obtained show that the oxidation of S2− into S6+ in the glass is responsible for the precipitation of copper nanoparticles. The development of a sulphide-silicate partition and the presence of Fe3+ in the melt give rise to the precipitation of the high-pressure tetragonal polymorph of chalcocite (Cu2S). Differences between the Medieval and Renaissance red glass are determined.

Colorimetric detection of uric acid based on enhanced catalytic activity of cobalt-copper bimetallic-modified molybdenum disulfide

A method for the quantification of uric acid (UA) by colorimetry using a four-in-one nanocomposite MoS2/PDA/CoCu as a novel nanozyme was proposed. The nanocomposite was prepared based on the deposition of metal cobalt and copper nanoparticles onto the surface of MoS2 nanosheets using polydopamine (PDA) as a stabilizer. The Michaelis-Menten model was used to monitor the catalytic efficiency of peroxidase-like reactions, and the results showed that the Michaelis constant Km (0.0076 mM and 0.0032 mM) values calculated by the Lineweaver-Burk equation were much lower than those of horseradish peroxidase and other reported nanozymes, demonstrating that MoS2/PDA/CoCu has excellent peroxidase-like activity. Theoretically, uric acid can produce allantoin and H2O2 in the presence of uricase and oxygen, respectively. The nanocomposite efficiently catalyzes H2O2 to produce hydroxyl radicals (•OH) that then oxidize colorless 3, 3′, 5, 5′-tetramethylbenzidine (TMB) to the blue oxidation product (ox-TMB) which corresponds to the characteristic absorption peak at 652 nm. Using optimal conditions, we constructed a sensitive visible visual colorimetric method combined with a designed smartphone for UA detection (0.5–200 μM, R2 = 0.995) with a limit of detection (S/N = 3) of 0.13 μM. When UA was detected in serum and urine samples, good recovery rates were obtained, indicating the great potential of this method for the detection of uric acid in clinical and daily life applications.

WITHDRAWN: Integrated Matrix Incorporating Imidazole Graphene Assembled Metallic Copper and Silver Nanoparticles to be a Fluidic Antenna Device

: Since the authors are not responding to the editor’s requests to fulfill the editorial requirement, therefore, the article has been withdrawn. The Bentham Editorial Policy on Article Withdrawal can be found at https://benthamscience.com/editorial-policies-main.php Bentham Science Disclaimer: It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript, the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication.

Cytotoxic, apoptotic and necrotic effects of starch coated copper nanoparticles on Capan 1 pancreatic cancer cells

In the present study we utilized a green synthesis approach by reduction route with ascorbic acid in the presence of starch as the capping agent. Here we aimed to generate a stable starch coating copper nanoparticles (Cu-SNPs) and to investigate their apoptotic and necrotic effects on Capan 1 pancreatic cancer cell line. The water soluble monodisperse starch-protected zero-valent copper nanoparticles were characterized by transmission electron microscopy, XPS, FTIR analysis. TEM images showed that the presence of metallic copper nanoparticles with anisotrophic morphologies and the sizes of 90% copper nanoparticles were in 50 nm and 80 nm range. Cetyltrimethylammonium bromide (CTAB) coated copper nanoparticles was also synthesized to compare the stability of starch coating copper nanoparticles. It was also found that copper nanoparticles were significantly protected by starch coating. Cu-SNPs exhibited stronger antimicrobial effects on Staphylocossus and Enterococcus. In vitro cell culture studies demonstrated that Cu-SNPs were not cytotoxic on L929-fibroblasts and Capan 1 pancreatic cancer cell in all concentrations used here (6.25–100 ppm) in different extends. The cytotoxic, necrotic, and apoptotic effects of Cu-SNPs on the Capan 1 pancreatic cancer cell line have been exhibited. Furthermore, the micronucleus test and hemolytic activity test were also performed.