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A modified carbon paste sensor based on N,N'-(((ethane-1,2-diylbis(oxy))bis(2,1-phenylene))bis(methanylylidene))bis(pyridine-2-amine; BPA Schiff base as Cr(III) selective carrier was fabricated and studied in this work. The proposed sensor homogenization and mechanism of action was studied by infra-red (IR) and scanning electron microscope (SEM) with energy dispersive X-ray (EDX) tools. The sensor covered 1.0 × 10-7-1.0 × 10-1 mol L-1 linear range and a detection limit of 7.22 × 10-8 mol L-1 for Cr(III) with 20.17 ± 0.13 mV decade-1 Nernstian slope. 5 s was the response time of the prepared sensor and it was reproducible and stable for 3 months. The working pH range was 3.3-6.0 and it also works well to determine Cr(III) ion in presence of water miscible solvents up to 12.5% content of the methanol and 17.5% of ethanol. The electrode's selectivity was studied using separate and mixed solution methods for selectivity coefficients determination and the sensor showed good selectivity relative to a variety of metal ions (selectivity coefficients = 1.01 × 10-5-8.57 × 10-3). In addition, the practical analysis value of the sensor was demonstrated by measurement of Cr(III) quantitatively in mineral water, supplement and also as an indicator electrode in Cr(III) against EDTA potentiometric titration with good reproducibility (RSDs of 0.91-2.15%).

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Using E-beam irradiation as an eco-friendly technique for initiation and crosslinking, a series of Hydroxyethyl Cellulose-poly vinyl alcohol copolymer hydrogels were synthesized as templates for cuprous oxide (Cu2O), reduced graphene oxide (rGO) and bismuth vanadate (BiVO4) nanoparticles to be used as nanocomposites photocatalysts for methylene blue (MB) dye decolorization using visible light. Preparation conditions were optimized to ensure the construction of a good network architecture and therefore the highest gelation degree. For the preparation of (Cu2O@rGO)/BiVO4 nanocomposites, a series of rGO was decorated by Cu2O using the precipitation method, followed by mixing with BiVO4 which was synthesized hydrothermally. (EDX), (XRD), (TEM), and (SEM) were used for nanoparticle characterization. The thermal characteristics of the fabricated nanocomposites were evaluated using thermal gravimetric analysis. The presence of rGO enhanced the decolorization efficiency of MB about 20 % higher than that of (HEC-PVA)/Cu2O which achieves only (59 %) decolorization efficiency. After the addition of BiVO4 NPs, the decolorization efficiency increased to reach 90 % after 150 min at pH 11 using a 10 ppm MB solution. The developed (HEC-PVA)/(Cu2O@rGO)/BiVO4 photocatalyst exhibits efficient reusability for 5 cycles. Treated dyed water shows a germination index (GI) of 82 % suggesting its suitability for irrigation of playgrounds and gardens.

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Epilepsy is one of the most serious worldwide neurological disorders that lead to the cognitive-psychosocial insults in recurrent seizures. About one third of the patients are drug-resistant, so innovative drugs are needed to manage seizures to improve the quality of life. Ceftriaxone is a cephalosporin antibiotic that increases the expression of glutamate transporters-1 and improves the neurobehavioral effects caused by increased glutamate level in the CNS. Selenium is well known antioxidant. The present study aimed to investigate ceftriaxone and selenium therapeutic effects against epilepsy in rats. Epilepsy was induced by PTZ given at a dose (50 mg/kg I.P) on alternative days for 13 days. Eighty rats were randomly divided into 8 groups: Group1-2; normal and vehicle control, Group 3; PTZ group, Group 4-8; kindled rats received selenium, ceftriaxone100, ceftriaxone200, selenium + ceftriaxone100 and selenium + ceftriaxone200 mg/kg/day respectively for a week. At the end of the study, behavioral tests were performed. Oxidative stress, inflammatory markers, neurotransmitters and GLT-1 were measured in brain tissue homogenate. Brain histopathological investigation was also done. PTZ-kindled rats exhibited increased Racine score, besides behavioral tests and histopathological changes, significant elevation in oxidative stress and inflammatory markers, with decrease in serotonin, dopamine, GABA levels and GLT-1 expressions. Selenium and Ceftriaxone alone or combined treatment decreased Racine score with remarkable improvement in behavioral and histopathological changes. The antioxidant enzymes, neurotransmitters and GLT-1 expressions were increased, along with reduced TNF-α, IL-1 levels. Current study showed that selenium + ceftriaxone100 group represents a possible approach to improve epilepsy particularly through inhibiting oxidative stress and inflammation.

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Nanocomposite hydrogels composed of magnesium oxide (MgO) and natural polymer-based copolymer of Xanthan gum (Xan) and acrylic acid (AAc) were prepared using radiation-induced copolymerization and crosslinking technique to be used as a drug delivery system. MgO nanoparticles were synthesized using sol- gel method. FTIR, XRD, UV-vis and TEM analysis revealed the successful preparation of MgO nanoparticles. The size of MgO nanoparticles was found to be 6.6 nm. FTIR data confirmed the incorporation of MgO within the (Xan-AAc) copolymer hydrogel. The presence of MgO nanoparticles slightly decreases the gelation degree and on contrary the swelling degree and network porosity was enhanced. (Xan-AAc)/MgO nanocomposites show typical pH-dependent swelling behavior Moreover, the swelling kinetics showed that all the samples under investigation possess Fickian at pH1 and non-Fickian at pH7. Methotrexate (MTX) as model for anticancer drugs was used to evaluate the potential efficiency of the obtained (Xan-AAc)/MgO nanocomposites as drug carrier. Incorporation of MgO into (Xan-AAc) hydrogel improves the drug loading efficiency and enhances the (MTX) release to reach maximum in the simulated intestine medium (pH7). The drug release profile came in a good agreement with swelling results which recommend the (Xan-AAc)/MgO nanocomposite hydrogels as potential targeted drug delivery system.

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Depending on the biocompatibility of Xanthan, polyvinyl alcohol and the antibacterial efficiency of zinc oxide nanoparticles (ZnO), a series of (Xanthan-polyvinyl alcohol)/ZnO nanocomposite hydrogels were prepared as wound dressing using eco-friendliness 60Co γ-ray irradiation facility. ZnO nanoparticles were characterized using X-ray diffraction, UV-vis spectroscopy, transmission electron microscopy and energy dispersive X-ray analysis. The size of ZnO nanoparticles was ranged between 15 and 25 nm. The presence of ZnO nanoparticles reconstructed the internal structure of the hydrogel network which aid in a homogenous porous structure as indicated by scanning electron micrographs. Such adequate porosity along with the presence of ZnO nanoparticles controls the fluid uptake ability, water retention and water vapor transmission rate. The fluid uptake ability in pseudo-extracellular fluid and water ranged between (554-664%) and (1281-1603%), respectively. After exposure to air for 6 h, ZnO dressings kept about 50-65% of their water content which makes them more suitable for moderate exudating wounds. Water vapor transmission rate ranged between 167 and 184 (g/(m2 h) which is sufficient to keep wound's surface moist. ZnO dressings show an efficient microbial barrier potency and profound antimicrobial activity against Staphylococcus aureus, Escherichia coli and Candida albicans. In vitro cytotoxicity and haemolytic potency evaluation showed their biocompatibility.

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