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Background: Tumor-promoting factors (TPF) and metabolic reprogramming are hallmarks of cancer cell growth. This study is designed to combine the newly synthesized two nanocomposites DDM (HA-FA-2DG@DCA@MgO) and AF (HA-FA-Amygdaline@Fe2O3) with fractionated doses of radiotherapy (6 Gy-FDR; fractionated dose radiotherapy) to improve the efficiency of chemo-radiotherapy against breast cancer cell lines (BCCs; MCF-7 and MDA-MB-231). The physicochemical properties of each nanocomposite were confirmed using energy dispersive XRD, FTIR, HR-TEM, and SEM. The stability of DDMPlusAF was also examined, as well as its release and selective cellular uptake in response to acidic pH. A multiple-MTT assay was performed to evaluate the radiosensitivity of BCCs to DDMPlusAF at 3 Gy (single dose radiotherapy; SDR) and 6 Gy-FDR after 24, 48, and 72 h. Finally, the anti-cancer activity of DDMPlusAF with 6 Gy-FDR was investigated via assessing the cell cycle distribution and cell apoptosis by flow cytometry, the biochemical mediators (HIF-1α, TNF-α, IL-10, P53, PPAR-α, and PRMT-1), along with glycolytic pathway (glucose, HK, PDH, lactate, and ATP) as well as the signaling effectors (protein expression of AKT, AMPK, SIRT-1, TGF-β, PGC-1α, and gene expression of ERR-α) were determined in this study. Results: The stability of DDMPlusAF was verified over 6 days without nanoparticle aggregation. DDMPlusAF release and selectivity data revealed that their release was amenable to the acidic pH of the cancer environment, and their selectivity was enhanced towards BCCs owing to CD44 and FR-α receptors-mediated uptake. After 24 h, DDMPlusAF boosted the BCC radiosensitivity to 6 Gy-FDR. Cell cycle arrest (G2/M and pre-G1), apoptosis induction, modulation of TPF mediators and signaling effectors, and suppression of aerobic glycolysis, all confirmed DDMPlusAF + 6 Gy's anti-cancer activity. Conclusions: It could be concluded that DDMPlusAF exerted a selective cancer radiosensitizing efficacy with targeted properties for TPF and metabolic reprogramming in BCCs therapy. [ABSTRACT FROM AUTHOR]

The bacterial wilt is a global destructive plant disease that initiated by the phytopathogenic Ralstonia solanacearum. This study display a novel biofabrication of silica/silver nanocomposite using Fusarium oxysporum-fermented rice husk (RH) under solid state fermentation (SSF). The biofabricated nanocomposite was characterized by XRD, UV–Vis. spectroscopy, DLS, SEM, EDX elemental mapping, and TEM analyses as well as investigated for anti-R. solanacearum activity. Response surface methodology was also processed for optimizing the biofabrication process and improving the anti-bacterial activity of the fabricated nanocomposite. Maximum suppression zone of 29.5 mm against R. solanacearum was reached at optimum RH content of 6.0 g, AgNO3 concentration of 2.50 mM, reaction pH of 6.3, and reaction time of 2 days. The anti-R. solanacearum activity of the fabricated nanocomposite was further improved by exposing the F. oxysporum strain to a gamma irradiation dose of 200 Gy. In conclusion, RH recycling under SSF by F. oxysporum could provide an innovative, facile, non-expensive, and green approach for fabricating SiO2/Ag nanocomposite that could be applied efficiently as an eco-friendly antibacterial agent to combat R. solanacearum in agricultural applications. Moreover, the developed method could serve as a significant platform for the designing of new nanostructures for broad applications. Key points: Biofabricated SiO2/Ag nanocomposite by gamma irradiated-F. oxysporum under SSF. Statistical optimization and complete characterization of SiO2/Ag nanocomposite. Application in agriculture for combating the wilt causing R. solanacearum. [ABSTRACT FROM AUTHOR]

Herein, this work aims to reveal the gamma irradiation-assisted the sol–gel method for the synthesis of silver (Ag) modified-nickel molybdate nanoparticles (NiMoO4; NMO NPs) and tested for their antimicrobial and antibiofilm activities against some pathogenic bacteria and unicellular fungi. The prepared samples were characterized via XRD, HR-TEM, SEM, EDX, and elemental mapping analysis. The antimicrobial potential was tested as ZOI and MIC, while antibiofilm was estimated by tube method. The detected diffraction peaks of bare NMO NPs affirmed the successful synthesis of NMO NPs without any foreign phases. Also, three diffraction peaks were detected affirming the formation of Ag NPs on the surface of NMO NPs. The average crystallite size for the bare NMO NPs and Ag@NMO NPs was found to be 71.8 nm and 48.28 nm, respectively. Also, the SEM images have illustrated the decoration of Ag NPs on the NMO surface. Further, the TEM image illustrated that the particles of NMO possess a hexagonal shape in the nanoscale regime. Also, the elemental mapping images confirm the uniform distribution of these elements over the Ag@NMO sample. Antimicrobial results revealed that the synthesized Ag@NMO NPs recorded the most significant inhibition zone more than NMO NPs against Enterococcus columbae (33.3 ± 0.115 mm), and Candida albicans (30.8 ± 0.572 mm), and the lowest MIC (0.048 µg/ml) against E. columbae. Antibiofilm activity of Ag@NMO NPs recording 94.32% for E. columbae, 91.99% for S. vitulinus, and 90.98% for C. albicans. SEM imaging in the lack of Ag@NMO NPs exhibited normally grown bacterial cells with standard typical semi-formed biofilm. After Ag@NMO NPs treatment, remarkable morphological changes; including the total lysis of the outer surface attended by deformations with the reduction in the whole viable number. [ABSTRACT FROM AUTHOR]

The rapid urbanization and industrialization is causing worldwide water pollution, calling for advanced cleaning methods. For instance, pollutant adsorption on magnetic oxides is efficient and very practical due to the easy separation from solutions by an magnetic field. Here we review the synthesis and performance of magnetic oxides such as iron oxides, spinel ferrites, and perovskite oxides for water remediation. We present structural, optical, and magnetic properties. Magnetic oxides are also promising photocatalysts for the degradation of organic pollutants. Antimicrobial activities and adsorption of heavy metals and radionucleides are also discussed. [ABSTRACT FROM AUTHOR]

Cinnamon verum was used as a low‐cost precursor to produce microporous‐activated carbons with a high surface area (894 m2/g) and large total pore volume (0.49 cm3/g). Thermogravimetric analysis scanning electron microscopy, Fourier‐transform infrared spectroscopy, Brunauer–Emmett–Teller surface area, and pore size analyzer techniques were used to characterize the new sorbent. The new porous carbon's ability to remove chlorpyrifos (CPS), an organo‐phosphorus surrogate of ware gases and the active component in most insecticides and pesticides, has been assessed by a batch adsorption procedure. Different sorption factors such as initial CPS concentrations, contact time, pH, solution temperature, and sorbent dosage have been studied. The results show that the new sorbent could remove 100% of CPS at low concentrations of 20 ppm within 20 min of contact time under a favorable sorption process. CPS adsorption was found to be exothermic, and the adsorption capacity decreases with increasing temperature. Equilibrium results were modeled using three isotherm models: Langmuir, Freundlich, and Temkin. The Langmuir isotherm model was found to be the best model to represent the CPS adsorption data. The kinetic results were fitted to pseudo–first‐order, pseudo–second‐order, and intraparticle diffusion models and thoroughly followed the pseudo–second‐order kinetic model. Thermodynamic factors such as enthalpy (ΔHo), entropy (ΔSo), and free energy (ΔGo) were assessed. The negative values of ΔHo and ΔGo indicate the exothermic and spontaneous nature of the adsorption process. The sorbent from waste cinnamon bark was economically practical and eliminates organophosphorus compounds from aqueous solutions. [ABSTRACT FROM AUTHOR]

The impact of bacterial diseases and the development of effective antimicrobial agents have drawn much consideration as a main healthcare challenge. The effects of montmorillonite/silver nanocomposites (MMT/Ag NCs) as a nanofiller on mechanical and thermal properties of linear low-density polyethylene/ethylene–vinyl acetate copolymers blend (LLDPE/EVA) had been investigated. The antimicrobial potential of the synthesized samples had been studied. The developed LLDPE/EVA/MMT/Ag nanocomposites films (NCFs) had been characterized by UV–Vis. spectroscopy, FTIR and XRD analysis. The mechanical, and thermal properties of LLDPE/EVA/MMT/Ag NCFs had been investigated. The results showed that incorporating the MMT/Ag NCs at lower phr (part per hundred resins) content resulted in both improvement in the mechanical properties and the thermal stability. The antimicrobial results demonstrated that LLDPE/EVA blend with 5 phr MMT/Ag NCs possesses the most powerful impact on the tested microbes. The SEM analysis of the treated cells showed, noticeable morphological abnormalities (the complete lysis of the outer surface followed by deformations of cells). Accordingly, the synthesized nanocomposites open the area of interest for possible application in a broad range of purposes like environmental and biomedical applications. [ABSTRACT FROM AUTHOR]

Since the beginning of the third Millennium, specifically during the last 18 years, three outbreaks of diseases have been recorded caused by coronaviruses (CoVs). The latest outbreak of these diseases was Coronavirus Disease 2019 (COVID-19), which has been declared by the World Health Organization (WHO) as a pandemic. For this reason, current efforts of the environmental, epidemiology scientists, engineers, and water sector professionals are ongoing to detect CoV in environmental components, especially water, and assess the relative risk of exposure to these systems and any measures needed to protect the public health, workers, and public, in general. This review presents a brief overview of CoV in water, wastewater, and surface water based on a literature search providing different solutions to keep water protected from CoV. Membrane techniques are very attractive solutions for virus elimination in water. In addition, another essential solution is nanotechnology and its applications in the detection and protection of human and water systems. [ABSTRACT FROM AUTHOR]

In this study magnesium ferrite nanoparticles (MgFe2O4 NPs) were synthesized through an aqueous co-precipitation method and functionalized with citric acid (CA) for outstanding their antimicrobial potential and removal activity of azo dye. MgFe2O4 NPs and CA-MgFe2O4 NPs were characterized by XRD, HRTEM, SEM, EDX, FT-IR, and SEM/EDX mapping method to analyze crystallinity, average particle size, morphology, functional groups and elemental composition, respectively. Antimicrobial activity was investigated against pathogenic bacteria and yeast as zone of inhibition (ZOI) and minimum inhibitory concentration (MIC). Reaction mechanism using SEM/EDX analysis of CA-MgFe2O4 NPs-treated microbial cells was mentioned. The removal efficiency was tested against methyl orange (MO), and various parameters affecting the removal efficiency such as (pH on removal of MO, MO initial concentration, and CA-MgFe2O4 dose) were studied. Antimicrobial results showed that CA-MgFe2O4 NPs demonstrated maximum activities against S. aureus, E. coli, and C. albicans with ZOI of 20.0, 16.0, and 14.0 mm, respectively. Results obtained suggested that 0.1 g of CA-MgFe2O4 NPs achieved 85.0% removal of MO at pH 5.0.0, hence, it exhibited efficient dye removal and sufficient antimicrobial activities. [ABSTRACT FROM AUTHOR]

While ferric oxide is frequently used as a catalyst, aluminum, with combustion enthalpy 32000 J g−1, is a versatile highly energy-dense material. This binary mixture can achieve a synergistic impact with a strong thermite reaction. Additionally, nanoscale particles can offer better interfacial surface area, catalytic effect, and a high heat release rate. This study reports on the facile fabrication of colloidal ferric oxide nanoparticles (Fe2O3 NPs) of 5-nm average size; aluminum nanoplates of 100 nm were employed. Colloidal nanothermites (Fe2O3/Al) were synthesized and integrated into ammonium perchlorate (APC) via co-precipitation. Uniform dispersion of nanothermite particles into APC was confirmed via elemental mapping using an EDAX detector. The nanothermite mixture's potentials (as a catalyst and highly energy-dense material) was described by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Thermite NPs offered a decrease in APC endothermic phase change by 48%, increasing the total heat released by 68%. While APC demonstrated a decomposition enthalpy of 836 J/g, for the APC nanocomposite it was 1405 J/g. Aluminum particles increased decomposition enthalpy, and Fe2O3 NPs acted as an effective catalyst to decrease the required activation energy. The kinetic decomposition study of APC nanocomposite was investigated via isothermal heating using TGA. Nanothermite particles offered a reduction in APC activation energy by 11% and 14% using Kissinger's and Kissinger–Akahira–Sunose (KAS) models, respectively. Herein, this is the first report on catalytic activity assessment of colloidal nanothermite particles on APC decomposition. [ABSTRACT FROM AUTHOR]

The world is currently facing critical water and energy issues due to the growing population and industrialization, calling for methods to obtain potable water, e.g., by photocatalysis, and to convert solar energy into fuels such as chemical or electrical energy, then storing this energy. Energy storage has been recently improved by using electrochemical capacitors and ion batteries. Research is actually focusing on the synthesis of materials and hybrids displaying improved electronic, physiochemical, electrical, and optical properties. Here, we review molybdenum disulfide (MoS2) materials and hybrids with focus on synthesis, electronic structure and properties, calculations of state, bandgap and charge density profiles, and applications in energy storage and water remediation. [ABSTRACT FROM AUTHOR]

One of the biggest global threats to contemporary medicine and society at large is antibiotic resistance, which is also one of the least understood by professionals and the general public. Emerging crystalline materials called metal-organic frameworks (MOF) find extensive uses in biomedical engineering. Because of their excellent stability, and high porosity, MOFs are useful platforms for designing a variety of disinfectant agents against some pathogenic microbes that causing serious diseases. In this work, the effective hydrothermal synthesis of MIL-101(Cr) as a MOF substance was the main focus of originality and scientific value. Then, using a reduction-precipitation method, Fe2O3 material integrated the produced MOF structure. To synthesize the TiO2/Fe3O4/MIL-101(Cr) composite, we used a simple hydrothermal in situ growth technique. The XRD and HR-TEM analyses of the newly synthesized MOF-Fe2O3/TiO2 composite essentially confirmed its crystallinity and formation with the precise shape and size. Data clearly demonstrated that Candida albicans was the most susceptible organism to all three kinds of synthesized samples, with documented MIC values for MOF-Fe2O3/TiO2 at 62.5 µg mL− 1. Results further revealed that MOF-Fe2O3/TiO2 had the same MIC values of 62.5 µg mL− 1 against Staphylococcus aureus, and Bacillus subtilis. Positively, the amount of bacterial protein removed is directly proportional after increasing the concentration of MOF, MOF-Fe2O3, and MOF-Fe2O3/TiO2 and counted to be 99.89, 200.89, and 410.10 µg mL− 1 following the treatment with MOF, MOF-Fe2O3, and MOF-Fe2O3/TiO2, respectively. The promising results demonstrates the antibacterial features of the MOF-Fe2O3, and MOF-Fe2O3/TiO2 and describes the appearance of holes in the S. aureus membrane, which help in making the proteins bleed out from the S. aureus cytoplasm. Eventually, after irradiation with gamma dose (100.0 kGy), the potential antimicrobial activity of the synthesized MOF-Fe2O3/TiO2 was increased. [ABSTRACT FROM AUTHOR]

Two dimensional (2D) graphene and its derivatives modification with nanomaterials for formation of hybrid/nanocomposites undergo stimulus-induced optical and electrical changes which are important for many new switchable device technologies. The feature article deals with a straight forward and versatile technique for the fabrication of semiconductor nanomaterials (CdS and TiO2) nanomaterials dispersed liquid crystals (NDLC) or graphene dispersed liquid crystal (GDLC) by stretching hydrogen bonds (H-) in the precursor droplets between two substrates to form a liquid bridge. Fewer liquid crystals (LCs) possess a conventional oriented nematic phase with optimal performances. Evolving advantages of thin-film nanocomposite materials and switchable devices have fueled several developments in the field of flexible electronics, high contrast ratio smart display and opto-electronics. These advantages have been complemented with the expansion of novel composite materials such as GDLC and NDLC as sensors to monitor the inflammability, explosive nature and toxicity of chemicals. This discussion also delves into the fabrication of graphene assembly polymer nanocomposites dispersed in LCs, the necessity for bio-polymer incorporation and their bio-sensing and antimicrobial applications. Additionally, discussed the issues and challenges associated with understanding and exploiting the potentials of smart switchable devices fabricated by nanomaterials or polymer/graphene hybrid composite matrix. Following substantial development and optimized over decades, a novel mechanism employed in smart switchable devices via GDLC hybrid nanocomposite matrix has been found to offer numerous benefits including being cost-effective, possessing a large area compatibility and large scalability in addition to seamless heterogeneous integration. [ABSTRACT FROM AUTHOR]

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 (H 2 O 2) 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. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (RGO) possesses unique thermal and optical properties. It could act as black body emitter with high-infrared emissivity. RGO could meet wide applications in advanced infrared decoy flares. In this study, RGO nano-sheets were synthesized through the reduction of GO after applying Hummers' method using graphite powder as a precursor. The synthesized RGO owns 10 µm dimensions and 10 nm thicknesses. TEM analysis revealed the amorphous structure of the prepared nano-sheets. XRD diffractogram demonstrated the amorphous RGO structure. Moreover, Raman spectroscopy confirmed the complete reduction of GO into RGO. In addition, decoy flare formulations based on RGO, reactive metal fuels, and fluorocarbon polymer were developed. Additionally, thermal signature was evaluated using Arc-Optics IR spectrometer (1–6 µm) to reference formulation. Our results revealed that nanocomposite flare based on 6 wt % RGO demonstrated superior spectral intensity with an increase in average intensity by 147%. Moreover, advanced radiometric performance with superior relative intensity value (Ɵ) of 0.7 was recorded. To sum up, RGO can act as an excellent source of carbonaceous materials that can strengthen incandescence emission. Surplus magnesium could vaporize and combust with substantial heat output that could promote black body emission. [ABSTRACT FROM AUTHOR]

This work reports the detailed structural characterization of Zn2+ ion-substituted cobalt ferrite nanoparticles (CFO NPs; Co1−xZnxFe2O4; x = 0.00, 0.25, 0.50, and 0.75), prepared using a facile sol–gel method. It correlates structural changes with magnetic and dielectric properties. The as-synthesized samples were investigated by X-ray diffraction (XRD) analysis, BET surface area analyzer, energy-dispersive X-ray (EDX), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), Mössbauer spectroscopy, and impedance analyzer. The pristine sample (CFO) comprised of NPs with 25 nm size, which decreased up to 11 nm upon the formation of Zn0.75Co0.25Fe2O4. The N2 adsorption–desorption isotherm of the prepared Zn0.5Co0.5Fe2O4 sample confirmed the presence of a mesoporous structure. SEM images revealed that all prepared samples exhibited porous surface with honeycomb-like structures. The cationic distribution was described by Mössbauer spectra. The increment of Zn ions in the prepared samples resulted in sharp reduction of saturation magnetization and remanence values. The normal dielectric dispersion behavior was recorded and can be ascribed to the Maxwell–Wagner type polarization. Besides, the dielectric parameters varied by increasing Zn content in CFO NPs. This may be ascribed to O2 vacancies and Fe3+ ions in A- and B-sites. Dielectric studies revealed that, content of Zn ions beyond x = 0.25 was sufficient to reduce both dielectric constant and loss at low frequencies. [ABSTRACT FROM AUTHOR]

Even though HMX is one of the most powerful highly explosive materials; HMX-based propellants demonstrated complexity of burning rate control as well as high pressure exponent (n). In addition, HMX is insensitive to common catalyst. TiO2 can offer novel catalyzing ability for HMX. Highly-crystalline, mono-dispersed TiO2 NPs of 5.0 nm particle size with proper surface area (26.87 ± 0. 36 m2/g) were fabricated using hydrothermal processing. TiO2 NPs were re-dispersed in organic solvent and effectively-integrated into HMX via co-precipitation technique; the impact of TiO2 NPs on HMX thermal behavior was investigated using DSC and TGA. TiO2 NPs exposed superior catalytic performance; the endothermic phase change of HMX at 187 °C was decreased by 43.3%. The main exothermic decomposition peak was decreased by 10 °C with enhanced total heat release by 46.7%. The catalytic performance of TiO2 NPs could be ascribed to the release of active surface ȮH radicals that could induce HMX decomposition via hydrogen abstraction. Furthermore, TiO2 NPs could adsorb evolved NO2 on its surface with surge in total heat release in condensed phase. [ABSTRACT FROM AUTHOR]

Precise tailoring of nanostructured cobalt ferrite paves the way to design and develop devices for stress and noncontact torque sensors. Herein, Mn2+ ions are inserted into cobalt ferrite with different ratios using a facile sol–gel method. The as-synthesized ferrites are characterized via energy dispersive X-ray (EDX), Fourier transforms infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), high resolution transmission electron microscope (HR-TEM), thermogravimetric analysis (TGA), electrochemical impedance spectroscopy (EIS), and vibrating sample magnetometer (VSM). EDX analyses affirm the stoichiometry of the synthesized samples with the intended ratios. The FTIR and XRD prove the presence of a single-phase cubic spinel structure for all as-synthesized samples. The dislocation, the inter-chain distance and the distortion parameter values decrease with increasing Mn2+ content, which outweigh the improvement of the crystal structure of the doped CFO samples. SEM micrographs illustrate that the incorporation of Mn2+ significantly soars the porosity of the samples. TEM images reveal that the samples comprise particles in the nanometer range with spherical shape and porous nature. Thermal analyses show that the weight loss is dependent on Mn2+ content in the sample. For instance, at x = 0, a slight variation in the weight loss estimated by 8% is observed while at x = 0.25 the weight loss has reached up to 40%. The dielectric losses (8 × 105) of Co0.5Mn0.5 Fe2O4 is enough to meet the demands of microwave applications. Finally, a reduction in the magnetization of the pure CFO from 68.419 emu g−1 to 50.307 emu g−1 is achieved at x = 0.25. Herein, manganese substituted cobalt ferrites were synthesized using a facile sol–gel method. The Rietveld refinements of Co1-xMnxFe2O4 have studied. SEM images have indicated that the surface of the as-synthesized NPs has some porous shapes. EDX analyses have affirmed the stoichiometry of the samples. The TEM image reveals that particles are in the nanometer range. Thermal analyses show that the weight loss is dependent on Mn2+ content in the sample. The dielectric losses (8 × 105) of Co0.5Mn0.5 Fe2O4 is enough to meet the demands of microwave applications. The hysteresis loops reveal that the magnetic behavior of the CFO NPs is significantly influenced by Mn2+ ions substitution. Herein, manganese substituted cobalt ferrites were synthesized using a facile sol–gel method. The Rietveld refinements of Co1-xMnxFe2O4 have studied. SEM images have indicated that the surface of the as-synthesized NPs has some porous shapes. EDX analyses have affirmed the stoichiometry of the samples. The TEM image reveals that particles are in the nanometer range. Thermal analyses show that the weight loss is dependent on Mn2+ content in the sample. The dielectric losses (8 × 105) of Co0.5Mn0.5 Fe2O4 is enough to meet the demands of microwave applications. The hysteresis loops reveal that the magnetic behavior of the CFO NPs is significantly influenced by Mn2+ ions substitution. Highlights: Mn2+ is successfully incorporated into cobalt ferrite (CoFe2O4) via sol–gel method. XRD and Williamson-Hall analyses reveal that all samples comprise nanoparticles. SEM micrographs show that the samples' porosity soars with increasing Mn2+ content. TEM images reveal that the samples consist of spherical nanoparticle porous nature. The sample of the highest content of Mn2+ has the lowest Gibbs energy. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) nanocomposites have been extensively employed in many fundamental optoelectronic and photocatalytic applications due to their outstanding optical, electronic and chemical properties. In the present work, we introduce a simple layer-by-layer approach to design a magnetic TiO2 nanocomposite that could be easily recycled using an external magnetic field without affecting its quantum efficiency. The crystallinity, size, surface area, stability, morphology, purity and other optical, thermal and magnetic properties of the composite have been investigated. Surface topology, thickness and thermal conduction were also demonstrated by AC conductivity measurements at a specific temperature (55 °C). Our results revealed that the prepared composite has a semi-spherical concentric shape with an average size of about (123.4 nm), surface area of (46.13 m2/g) and zeta potential of (− 24.3 mV) as confirmed by HRTEM, surface area analyzer and zeta potential measurements. TGA and DSC analysis recorded the thermal stability of the composite up to (500 °C) while a band gap of about (3.35 eV) has been calculated. VSM analysis showed that the composite has good magnetic properties. Atomic force microscopy recorded a surface roughness of the composite of about (125 nm) while the average thickness was approximately (10.3 nm). Significant responses of the capacitance–voltage profiles in the employed Preisach model, have been also recorded. [ABSTRACT FROM AUTHOR]

Recently nanocomposites have become a super-growth inducers as well as vital antifungal agents, which enhance plant growth and suppress plant diseases. A new strategy regarding the fabrication of humic acid (H) and boron (B) conjugated Fe 2 O 3 nanocomposites was performed. Fe 2 O 3 NP-B and Fe 2 O 3 NP-H were synthesized in the presence of gamma-rays (as a direct reducing agent). Gamma-rays provoked reduction of metal ions due to the liberated reducing electrons, (e– aq), in aqueous solutions which can be considered as a direct reduction. Antifungal potential against Fusarium oxysporum , the causative agent of wilt disease in cucumber was determined. Disease index percent, metabolic resistance indicators in cucumber plant as response to promotion of systemic resistance (SR) were recorded. Results illustrated that both Fe 2 O 3 NPs-B and Fe 2 O 3 NPs-H nanocomposites had antifungal activity against F. oxysporum in vitro as well as in vivo. Results revealed that minimum inhibitory concentrations of Fe 2 O 3 NPs-B and Fe 2 O 3 NPs-H nanocomposites were 0.25 and 0.125 mM, respectively. Application of Fe 2 O 3 NPs-B (0.25 mM) and Fe 2 O 3 NPs-H (0.125 mM) appeared highly reduced the cucumber wilt disease symptoms incidence caused by F. oxysporum , and recorded disease severity by 83.33%. Fe 2 O 3 NPs-B was the best treatment reducing disease indexes by 20.83% and gave highly protection against wilt disease by 75.0% and came next Fe 2 O 3 NPs-H which reduced disease indexes by 25% and gave 69.99% protection against disease. Fe 2 O 3 NPs-B and Fe 2 O 3 NPs-H treatments improved morphological traits, photosynthetic pigments, osmolytes, total phenol and antioxidant enzymes activities in both infected and non-infected plants. The beneficial effects of the synthesized Fe 2 O 3 NPs-B and Fe 2 O 3 NPs-H nanocomposites were extended to increase not only the total phenol, and total soluble protein contents but also the activities of peroxidase (POD), and polyphenol oxidase (PPO) enzymes of the healthy and infected cucumber plants in comparison with control. • A new gamma-rays strategy regarding humic acid (H) and boron (B) conjugated Fe 2 O 3 nanocomposites fabrication was performed. • Antifungal potential against Fusarium oxysporum , the causative agent of wilt disease in cucumber was determined. • Disease index and metabolic resistance indicators in cucumber plant as response to systemic resistance promotion were verified. • Fe 2 O 3 NPs-B and Fe 2 O 3 NPs-H improved morphological behaviors, photosynthetic pigments and antioxidant enzymes activities. • The synthesized nanocomposites were increased the total phenol and soluble protein contents and POD and PPO enzymes activity. [ABSTRACT FROM AUTHOR]

Resistance mechanisms are a shelter for Acinetobacter baumannii to adapt to our environment which causes difficulty for the infections to be treated and WHO declares this organism on the top of pathogens priority for new drug development. The most common mechanism that develops drug resistance is the overexpression of the efflux pump, especially Resistance-nodulation-cell division (RND) family, to almost most antibiotics. The study is designed to detect RND efflux pump genes in A. baumannii, and its correlation to multidrug resistance, in particular, the carbapenems resistance Acinetobacterbaumannii (CRAB), and using different inhibitors that restore the antibiotic susceptibility of imipenem. Clinical A. baumannii isolates were recovered from different Egyptian hospitals in Intensive care unit (ICU). The expression of genes in two strains was analyzed using RT-PCR before and after inhibitor treatment. About 100 clinical A. baumannii isolates were recovered and identified and recorded as MDR strains with 75% strains resistant to imipenem. adeB, adeC, adeK, and adeJ were detected in thirty- seven the carbapenems resistance Acinetobacterbaumannii (CRAB) strains. Cinnamomum verum oil, Trimethoprim, and Omeprazole was promising inhibitor against 90% of the carbapenems resistance Acinetobacterbaumannii (CRAB) strains with a 2-6-fold decrease in imipenem MIC. Downregulation of four genes was associated with the addition of those inhibitors to imipenem for two the carbapenems resistance Acinetobacterbaumannii (CRAB) (ACN15 and ACN99) strains, and the effect was confirmed in 24 h killing kinetics. Our investigation points to the carbapenems resistance Acinetobacterbaumannii (CRAB) strain's prevalence in Egyptian hospitals with the idea to revive the imipenem activity using natural and chemical drugs as inhibitors that possessed high synergistic activity. [ABSTRACT FROM AUTHOR]

In this research, Orobanche aegyptiaca extract was utilized as an eco-friendly, and cost-effective green route for the construction of bimetallic silver-selenium nanoparticles (Ag-Se NPs). Bimetallic Ag-Se NPs were characterized by XRD, EDX, FTIR, HR-TEM, DLS, SEM/mapping and EDX studies. Antimicrobial, and antibiofilm potentials were tested against some selected pathogenic bacteria and unicellular fungi by ZOI, MIC, effect of UV exposure, and inhibition %. Reaction mechanism was assessed through membrane leakage assay and SEM imaging. HRTEM analysis confirmed the spherical nature and was ranged from 18.1 nm to 72.0 nm, and the avarage particle size is determined to be 30.58 nm. SEM imaging prove that bimetallic Ag-Se NPs presents as a bright particles, and both Ag and Se were distributed equally across O. aegyptiaca extract and Guar gum stabilizers. ZOI results showed that, bimetallic Ag-Se NPs have antimicrobial activity against S. aureus (20.0 nm), E. coli (18.5 nm), P. aeruginosa (12.6 nm), and C. albicans (18.2 nm). In addition, bimetallic Ag-Se NPs were able to inhibit the biofilm formation for S. aureus by 79.48%, for E. coli by 78.79%, for P. aeruginosa by 77.50%, and for C. albicans by 73.73%. Bimetallic Ag-Se NPs are an excellent disinfectant once it had excited by UV light. It was observed that the quantity of cellular protein discharged from S. aureus is directly proportional to the concentration of bimetallic Ag-Se NPs and found to be 244.21 μg/mL after the treatment with 1 mg/mL, which proves the antibacterial characteristics, and explains the creation of holes in the cell membrane of S. aureus producing in the oozing out of the proteins from the S. aureus cytoplasm. Based on the promising properties, they showed superior antimicrobial potential at low concentration (to avoid toxicity) and continued-phase durability, they may use in pharmaceutical and biomedical applications. [Display omitted] • Eco-friendly, and cost-effective green synthesis of bimetallic Ag-Se NPs using Orobanche aegyptiaca extract. • Ag-Se NPs were characterized by XRD, EDX, FTIR, HR-TEM, DLS, SEM/mapping and EDX analysis. • Ag-Se NPs showed superior antimicrobial potential at low concentration (to avoid toxicity) and continued-phase durability. • Ag-Se NPs performs a noted spots around the tested pathogenic bacteria, and confirmed the bleeding out of protein molecules from the membrane of bacterial cell. [ABSTRACT FROM AUTHOR]

Nature frequently provides narrative biological motivation. This study reports on oxygen-induced auto-polymerization of dopamine on the surface of medical cotton fibers to develop super-hydrophobic surfaces. The versatile reactivity of polydopamine (PDA) surfactant was adopted to deposit silver nanoparticles (Ag NPs) on the surface of medical cotton. SEM micrographs demonstrated the uniform deposition of Ag NPs. The antimicrobial reactivity confirmed the potential of Ag-loaded PDA-cotton fiber to hinder the growth of some tested pathogenic microbes. Silver-loaded PDA-cotton fibers showed the most promising zone of inhibition (ZOI) against (33.5 mm), Candida tropicalis (30.2 mm), and Aspergillus niger (30.2 mm). In growth curve assay, after addition of silver-loaded PDA-cotton fibers, the O.D. were lower (0.365 nm), showing the repression impact on S. aureus. It was observed that the quantity of cellular protein discharged from S. aureus is directly proportional to the concentration of silver-loaded PDA-cotton fibers and found to be 159.68 μg/ml after the treatment with silver-loaded PDA-cotton fibers (2 cm × 2 cm), which proves the antibacterial characteristics of the synthesied silver-loaded PDA-cotton fibers. The obtained antimicrobial results gives solution in treating pathogenic microbes and the application of silver-loaded PDA-cotton fibers as wound dressing in biomedical and pharmaceutical fields. • Oxygen-induced auto-polymerization of dopamine on the surface of medical cotton fibers to develop super-hydrophobic surfaces. • The versatile reactivity of polydopamine surfactant was adopted to deposit Ag NPs on the surface of medical cotton. • Antimicrobial activity confirmed the potential of Ag-loaded PDA-cotton fiber to hinder the growth of pathogenic microbes. • Antimicrobial results gives solution in treating pathogenic microbes and application as wound dressing in biomedical field. [ABSTRACT FROM AUTHOR]

Background: Bimetallic nanoparticles (BNPs) has drawn a lot of attention especially during the last couple of decades. A bimetallic nanoparticle stands for a combination of two different metals that exhibit several new and improved physicochemical properties. Therefore, the green synthesis and design of bimetallic nanoparticles is a field worth exploring. Methods: In this study, we present a green synthesis of silver nanoparticles (Ag NPs), selenium (Se) NPs, and bimetallic Ag-Se NPs using Gamma irradiation and utilizing a bacterial filtrate of Bacillus paramycoides. Different Techniques such as UV-Vis., XRD, DLS, SEM, EDX, and HR-TEM, were employed for identifying the synthesized NPs. The antimicrobial and antibiofilm activities of both the Ag/Se monometallic and bimetallic Ag-Se NPs were evaluated against some standard microbial strains including, Aspergillus brasiliensis ATCC16404, Candida albicans ATCC10231, Alternaria alternate EUM108, Fusarium oxysporum EUM37, Escherichia coli ATCC11229, Bacillus cereus ATCC15442, Klebsiella pneumoniae ATCC13883, Bacillus subtilis ATCC15442, and Pseudomonas aeruginosa ATCC6538 as a model tested pathogenic microbes. The individual free radical scavenging potentials of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs were determined using the DPPH radical scavenging assay. The degradation of methylene blue (MB) dye in the presence of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs was used to assess their photocatalytic behavior. Results: According to the UV-Vis. spectrophotometer, the dose of 20.0 kGy that results in Ag NPs with the highest O.D. = 3.19 at 390 nm is the most effective dose. In a similar vein, the optimal dose for the synthesis of Se NPs was 15.0 kGy dose with O.D. = 1.74 at 460 nm. With a high O.D. of 2.79 at 395 nm, the most potent dose for the formation of bimetallic Ag-Se NPs is 15.0 kGy. The recorded MIC-values for Ag-Se NPs were 62.5 µg mL− 1, and the data clearly demonstrated that C. albicans was the organism that was most susceptible to the three types of NPs. The MIC value was 125 µg mL− 1 for both Ag NPs and Se NPs. In antibiofilm assay, 5 µg mL− 1 Ag-Se NPs inhibited C. albicans with a percentage of 90.88%, E. coli with a percentage of 90.70%, and S. aureus with a percentage of 90.62%. The synthesized NPs can be arranged as follows in decreasing order of antioxidant capacity as an antioxidant result: Ag-Se NPs > Se NPs > Ag NPs. The MB dye degradation in the presence of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs was confirmed by the decrease in the measured absorbance (at 664 nm) after 20 min of exposure to sunlight. Conclusion: Our study provides insight towards the synthesis of bimetallic NPs through green methodologies, to develop synergistic combinatorial antimicrobials with possible applications in the treatment of infectious diseases caused by clinically and industrial relevant drug-resistant strains. [ABSTRACT FROM AUTHOR]