To achieve the advanced anticancer activity of nanocomposites fabricated with graphene oxide (GO), a novel procedure was used during the fabrication of chitosan (CS) or ethylene diamine tetra acetic ...acid (EDTA). The synthesized GO-based nanocomposites were distinguished through different analytical techniques. The cytotoxic activity was examined using MTT assays against three different cancer cell lines. Cell cycle distribution and apoptosis were studied by flow cytometry. Caspase-8, caspase-9, and VEGFR-2 levels were determined using the ELISA technique. HRTEM results revealed a regular 2D thin sheet with a transparent surface in non-modified GO and for GO-CS, the surface of GO has clear cuts and lines had developed due to CS insertion. Concerning the MCF-7 breast cancer cell line, the lowest IC
50
values were recorded, suggesting the most powerful cytotoxic effect on breast cancer cells. Treatment with GO-EDTA resulted in the lowest IC
50
value of 3.8 ± 0.18 μg mL
−1
. As indicated by the annexin V-FITC apoptosis assay, the total apoptosis highest percentage was in GO-EDTA treatment (30.12%). In addition, the study of cell cycle analysis showed that GO-EDTA arrested the cell cycle primarily in the G0/G1 phase (33.74%). CS- and EDTA-conjugated GO showed an anti-cancer activity through their cytotoxic effect against the MCF-7 breast cancer cell line.
To achieve the advanced anticancer activity of nanocomposites fabricated with graphene oxide (GO), a novel procedure was used during the fabrication of chitosan (CS) or ethylene diamine tetra acetic acid (EDTA).
A new strategy regarding the fabrication of chitosan (CS) or ethylene diamine tetraacetic acid (EDTA) on graphene oxide (GO) was performed. The nematocidal potential against Meloidogyne incognita ...causing root-knot infection in eggplant was tested. The plant immune response was investigated through measuring the photosynthetic pigments, phenols and proline contents, oxidative stress, and antioxidant enzymes activity. Results indicating that, the treatment by pure GO recorded the most mortality percentages of M. incognita 2nd juveniles followed by GO-CS then GO-EDTA. In vivo greenhouse experiments reveals that, the most potent treatment in reducing nematodes was GO-CS which recorded 85.42%, 75.3%, 55.5%, 87.81%, and 81.32% in numbers of 2nd juveniles, galls, females, egg masses and the developmental stage, respectively. The highest chlorophyll a (104%), chlorophyll b (46%), total phenols (137.5%), and free proline (145.2%) were recorded in GO-CS. The highest malondialdehyde (MDA) value was achieved by GO-EDTA (7.22%), and hydrogen peroxide (H2O2) content by 47.51% after the treatment with pure GO. Treatment with GO-CS increased the activities of catalase (CAT) by 98.3%, peroxidase (POD) by 97.52%, polyphenol oxidase (PPO) by 113.8%, and superoxide dismutase (SOD) by 42.43%. The synthesized nanocomposites increases not only the nematocidal activity but also the plant systematic immune response.
In this work, efficient methanol oxidation fuel cell catalysts with excellent stability in alkaline media have been synthesized by including transition metals to the layered double hydroxide (LDH) ...nanohybrids. The nanohybrids CoCr-LDH, NiCoCr-LDH and NiCr-LDH were prepared by co-precipitation and their physicochemical characteristics were investigated using TEM, XRD, IR and BET analyses. The nanohybrid CoCr-LDH is found to have the highest surface area of 179.87 m
g
. The electrocatalytic activity measurements showed that the current density was increased by increasing the methanol concentration (from 0.1 to 3 M) as a result of its increased oxidation at the surface. The nanohybrid NiCr-LDH, showing the highest pore size (55.5 Å) showed the highest performance for methanol oxidation, with a current density of 7.02 mA cm
at 60 mV s
using 3 M methanol. In addition, the corresponding onset potential was 0.35 V (at 60 mV s
using 3 M methanol) which is the lowest value among all other used LDH nanohybrids. Overall, we observed the following reactivity order: NiCr-LDH > NiCoCr-LDH > CoCr-LDH, as derived from the impedance spectroscopy analysis.
Abstract A new fundamental mechanism for reliable engineering of zinc oxide (ZnO) nanorods to nanoplatelets grafted Mo 8 O 23 -MoO 2 mixed oxide with controlled morphology, composition and precise ...understanding of the nanoscale reaction mechanism was developed. These hybrid nanomaterials are gaining interest due to their potential use for energy, catalysis, biomedical and other applications. As an introductory section, we demonstrate a new expansion for the concept ‘materials engineering’ by discussing the fabrication of metal oxides nanostructures by bottom-up approach and carbon nanoparticles by top-down approach. Moreover, we propose a detailed mechanism for the novel phenomenon that was experienced by ZnO nanorods when treated with phosphomolybdic acid (PMA) under ultra-sonication stimulus. This approach is expected to be the basis of a competitive fabrication approach to 2D hybrid nanostructures. We will also discuss a proposed mechanism for the catalytic deposition of Mo 8 O 23 -MoO 2 mixed oxide over ZnO nanoplatelets. A series of selection rules (SRs) which applied to ZnO to experience morphology transition and constitute theory for morphology transition engineering (TMTE) will be demonstrated through the article, besides a brief discussion about possibility of other oxides to obey this theory.
In the last decade, nanosized metal organic frameworks (NMOFs) have gained an increasing applicability as multifunctional nanocarriers for drug delivery in cancer therapy. However, only a limited ...number of platforms have been reported that can serve as an effective targeted drug delivery system (DDSs). Herein, we report rational design and construction of doxorubicin (DOX)-loaded nanoscale Zr (IV)-based NMOF (NH
-UiO-66) decorated with active tumor targeting moieties; folic acid (FA), lactobionic acid (LA), glycyrrhetinic acid (GA), and dual ligands of LA and GA, as efficient multifunctional DDSs for hepatocellular carcinoma (HCC) therapy. The success of modification was exhaustively validated by various structural, thermal and microscopic techniques. Biocompatibility studies indicated the safety of pristine NH
-UiO-66 against HSF cells whereas DOX-loaded dual-ligated NMOF was found to possess superior cytotoxicity against HepG2 cells which was further confirmed by flow cytometry. Moreover, fluorescence microscopy was used for monitoring cellular uptake in comparison to the non-ligated and mono-ligated NMOF. Additionally, the newly developed dual-ligated NMOF depicted a pH-responsiveness towards the DOX release. These findings open new avenues in designing various NMOF-based DDSs that actively target hepatic cancer to achieve precise therapy.
Supercapacitors have the potential to be used in a variety of fields, including electric vehicles, and a lot of research is focused on unique electrode materials to enhance capacitance and stability. ...Herein, we prepared nickel molybdate/activated carbon (AC) nanocomposites using a facile impregnation method that preserved the carbon surface area. In order to study how the nickel-to-molybdenum ratio affects the efficiency of the electrode, different ratios between Ni-Mo were prepared and tested as supercapacitor electrodes, namely in the following ratios: 1:1, 1:2, 1:3, 1:4, and 1:5. X-ray diffraction, X-ray photoelectron spectroscopy, FESEM, HRTEM, and BET devices were extensively used to analyze the structure of the nanocomposites. The structure of the prepared nickel molybdates was discovered to be 2D hierarchical nanosheets, which functionalized the carbon surface. Among all of the electrodes, the best molar ratio between Ni-Mo was found to be 1:3 NiMo3/AC reaching (541 F·g−1) of specific capacitance at a current density of 1 A·g−1, and 67 W·h·Kg−1 of energy density at a power density of 487 W·Kg−1. Furthermore, after 4000 repetitive cycles at a large current density of 4 A·g−1, an amazing capacitance stability of 97.7% was maintained. This remarkable electrochemical activity for NiMo3/AC could be credited towards its 2D hierarchical structure, which has a huge surface area of 1703 m2·g−1, high pore volume of 0.925 cm3·g−1, and large particle size distribution.
A comprehensive overview and description of crumpled graphene explored in recent years for energy storage applications is presented. Although graphene is known as one of the best electronic ...materials, preparation of crumpled graphene has been less explored. This article selectively aims to present an overview of the advancement of research in crumpled graphene, in the areas of preparation and applications especially in energy storage, such as supercapacitors and lithium ion batteries. When graphene is transformed ino the crumpled form, the resulting material can give superior capacitance due to its unique properties like extremely high specific surface area, high conductivity and stability against graphitization (aggregation-resistant) compared to those of flat graphene sheets which tend to aggregate and thus lead to a dramatic decrease in the surface area, leading to poor capacitance.
This paper reviews the newest form of graphene (crumpled graphene) for energy storage applications.
To obtain the synergistic antimicrobial potential of nano-composites conjugated with graphene oxide (GO), an alternative approach was developed throughout the hybridization of chitosan (CS) or ...ethylene diamine tetraacetic acid (EDTA) with GO. The synthesized GO-nanocomposites were identified by XRD, HRTEM, SEM, FTIR, Zeta potential, and Raman spectroscopy. The antimicrobial activity of GO, GO-CS, and GO-EDTA was investigated against some pathogenic bacteria and Candida sp. Results showed that nano-composites looked flattened and clear, with some lines and folds on the exterior part. SEM images show the basic morphology of GO which owns remarkable holes, crevasses, and indeclinable internal structure. GO-EDTA and GO-CS possess a promising antimicrobial activity against all pathogenic microbes. In-vitro ZOI result verified that they exhibited activity against Escherichia coli (22.0 mm for GO-EDTA and 11.0 mm for GO-CS), Staphylococcus aureus (15.0 mm for GO-EDTA and 10.0 mm for GO-CS) and Candida albicans (22.0 mm for GO-EDTA and 16.0 mm for GO-CS). Microbial cells may be ultimately-damaged when they interact with GO-based nanocomposites due to different mechanisms such as oxidative and membrane stress and wrapping isolation. This work provides revolutionary GO-nanocomposites for increasing the antimicrobial activity against some pathogenic microbes with a cost-effective and eco-friendly approach.
The efficient electrocatalysts for direct methanol oxidation play an essential role in the electrochemical energy conversion systems for their application in a wide range of portable applications. ...Consequently, Cu-doped NiO thin films on fluorine-doped tin oxide (FTO) were successfully prepared by the co-sputtering deposition technique, using various deposition times (300, 600, 900, and 1200 seconds), and producing films of different thicknesses (30, 55, 90, and 120 nm, respectively). X-ray diffraction (XRD) revealed the ideal crystallinity of the structure of the prepared films and was used to observe the effect of the thickness of the films on the crystal size. Energy-dispersive X-ray spectroscopy (EDS) confirmed the purity of the deposited film without any contamination. Field emission scanning electron microscopy (FESEM) images confirmed the film thickness increase with increasing deposition time. The surface roughness value of the Cu-NiO 1200 film was found to be 3.2 nm based on the atomic force microscopy (AFM) measurements. The deposited thin films of different thicknesses have been used as electrocatalysts for methanol oxidation at various concentrations of methanol (0, 0.5, 1, and 2 M), and displayed the highest electrocatalytic performance in 1 M methanol. Cu-doped NiO thin films have the advantage as electrocatalysts where they can be used directly without adding any binder or conducting agents, this is because Cu-doped NiO is deposited with high adhesion and strong electrical contact to the FTO substrate. A clear impact on the catalytic activity with increasing film thickness and a correlation between the film thickness and its catalytic activity was observed. The current density increased by about 60% for the Cu-NiO 1200 sample compared to Cu-NiO 300 sample, with the lowest onset potential of 0.4 V
vs.
Ag/AgCl. All deposited thin films of different thicknesses exhibited high stability at 0.6 V in 1 M methanol. This will open the window toward using physical deposition techniques for optimizing the electrocatalytic activity of different catalysts for electrocatalytic applications.
The efficient electrocatalysts for direct methanol oxidation play an essential role in the electrochemical energy conversion systems for their application in a wide range of portable applications.
Ni-Al-CO
3
-layered double hydroxide (LDH) with Ni:Al ratio (3:1) and their nanocomposites with alginate and chitosan beads were prepared and examined for their efficiency in removal of Cd
2+
and Cu
...2+
ions from wastewater. Different parameters such as contact time, pH value, adsorbent weight, and heavy metal ion concentration on the removal efficiency were examined and reported. The prepared beads were examined using X-ray diffraction (XRD), TEM, SEM, and FTIR. Our results revealed a successful preparation of the LDH in rhombohedral hexognal crystal form and the alginate-LDH-chitosan beads. The optimized batch experiment conditions in ambient room temperature were found to be 2 g/L adsorbent dose, 50 mg/L initial concentration of meal, contact time of 2 h, and pH ~ 5 and 6 for removal of Cu
2+
and Cd
2+
, respectively. The adsorption process was well fitted with Langmuir and Freundlich isotherm models (higher
R
2
), with trivial advantage for Freundlich approach. Kinetic studies showed that the adsorption of both Cd
2+
and Cu
2+
followed the pseudo-second-order. The current study demonstrated that the Ni-Al-CO
3
LDH and their novel alginate-chitosan-based nanocomposite could be further tailored and used as efficient adsorbents for the uptake of heavy metals from wastewater.
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