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1.
Heliyon ; 9(6): e17106, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37484376

RESUMO

The activity of alginic acid as a cytotoxic agent was improved by structure modification using 4-aminophenol (4-AP) through condensation and polymerization processes. Then, silver nanoparticles were employed through doping to further enhance the cytotoxic activity of the modified polymer. The structure of the prepared materials was characterized by FT-IR, 1HNMR, UV spectroscopy, X-ray diffraction, and electron microscopy, and the thermal behavior of all synthesized materials was intensively studied. The cytotoxicity of the prepared compounds against cell lines of human hepatocellular (HepG-2) and lung (A-549) carcinomas was investigated. Alginic acid modified with 4-AP (Alg-4-AP3) showed the highest activity against HepG-2 and A-549 among all tested materials with IC50 values of 3.0 ± 0.19 µg/mL and 3.63 ± 0.23 µg/mL, respectively. Multitargeted molecular docking was employed to explore the binding modes of our compounds with the receptors EGFR, HER2, and VEGFR 2. The results revealed the inhibitory activity of our tested compounds against the proposed protein receptors, findings coincided with the in vitro results. In conclusion, the modification of alginic acid with 4-AP improved its cytotoxic activity against HepG-2 and A-549 cancer cells. In addition, doping the new materials with silver nanoparticles (AgNPs) further enhanced the cytotoxic activity.

2.
Membranes (Basel) ; 13(7)2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37505020

RESUMO

Water treatment is regarded as one of the essential elements of sustainability. To lower the cost of treatment, the wastewater volume is reduced via the osmotic process. Here, mixed-matrix woven forward osmosis (MMWFO) PES membranes modified by a TiO2/Na2Ti3O7 (TNT) nanocomposite were fabricated for treating water from different sources. Various techniques were used to characterize the TNT nanocomposite. The crystal structure of TNT is a mix of monoclinic Na2Ti3O7 and anorthic TiO2 with a preferred orientation of (2-11). The SEM image shows that the surface morphology of the TNT nanocomposite is a forked nano-fur with varying sizes regularly distributed throughout the sample. The impact of TNT wt.% on membrane surface morphologies, functional groups, hydrophilicity, and performance was investigated. Additionally, using distilled water (DW) as the feed solution (FS), the effects of various NaCl concentrations, draw solutions, and membrane orientations on the performance of the mixed-matrix membranes were tested. Different water samples obtained from various sources were treated as the FS using the optimized PES/TNT (0.01 wt.%) MMWFO membrane. Using textile effluent as the FS, the impact of various NaCl DS concentrations on the permeated water volume was investigated. The results show that the MMWFO membrane generated with the TNT nanocomposite at a 0.01 wt.% ratio performed better in FO mode. After 30 min of use with 1 M NaCl and various sources of water as the FS, the optimized MMWFO membrane provided a steady water flow and exhibited antifouling behavior. DW performed better than other water types whenever it was used owing to its greater flow (136 LMH) and volume reduction (52%). Tap water (TW), textile industrial wastewater (TIWW), gray water (GW), and municipal wastewater (MW) showed volume reductions of 41%, 34%, 33%, and 31.9%, respectively. Additionally, when utilizing NaCl as the DS and TIWW as the FS, 1 M NaCl resulted in more permeated water than 0.25 M and 0.5 M, yet a higher volume reduction of 41% was obtained.

3.
RSC Adv ; 12(39): 25654-25668, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36199339

RESUMO

Mixed matrix woven forward osmosis (MMWFO) membranes made of polyethersulfone (PES)/graphene oxide nanosheets (GO NSs) were made by inserting varying wt% ratios of GO NSs (zero to 0.1 wt%) into the PES matrix. A coated woven fabric material was used to cast the membrane polymer solution. The physical characteristics and chemical structures of the produced PES/GO MMWFO membranes were studied, including contact angle, hydrophilicity, porosity, tortuosity, function groups, chemical and crystallographic structures, nanomorphologies, and surface roughness. The performance of the prepared PES/GO FO membranes for water desalination was evaluated in terms of pure water flux (J w), reverse salt flux (J s), and salt rejection (SR). The hydrophilicity and porosity of the FO membrane improved with the addition of GO NSs, as did water permeability due to the development of multiple skin-layer structures with greater GO NS loading. These GO NSs establish shortcut pathways for water molecules to move through, reducing support layer tortuosity by three times, lowering support layer structural features, and minimizing internal concentration polarization (ICP). The PES/0.01 wt% GO MMWFO membrane with a total casting thickness of 215 µm and 1 M NaCl concentration had the best performance, with the highest J w (114.7 LMH), lowest J s (0.03 GMH), and lowest specific reverse solute flux (J s/J w = 0.00026 g L-1), as well as a more favorable structural parameter (S = 149 µm). The performance of our optimized membrane is significantly better than that of the control woven commercial cellulose triacetate (CTA) FO membrane under optimal FO conditions. As the NaCl concentration increased from 0.6 to 2 M, J w increased from 105 to 127 LMH which is much higher than the J w of the commercial one (7.2 to 15 LMH). Our FO membranes have an SR of 99.2%@0.65 M NaCl, which is significantly greater than that of the CTA membrane.

4.
ACS Omega ; 6(32): 20779-20789, 2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34423186

RESUMO

Polysulfanilic acid has a low efficiency for the photoelectrochemical (PEC) production of H2 from water splitting due to high recombination rate of charge and low electrical conductivity. Therefore, polyaniline was doped with polysulfanilic acid to form a copolymer and a blend to enhance its PEC heterogeneous catalytic performance. This was achieved through the improvement of visible light absorption and charge carriers' separation property. Herein, nine polymer samples of polysulfanilic acid were synthesized by oxidative polymerization. The structural, morphological, and optical properties of the synthesized polymeric materials were investigated. Interestingly, these polymer samples had multifunctional applications regarding their hydrogen generation efficiency. Photoelectrodes of different compositions from pure and blended polymers were prepared and used for the PEC solar hydrogen production from water. Different PEC parameters including the oxidant role, monochromatic illumination wavelength, and electrode reusability were optimized toward the efficient hydrogen generation. Moreover, the PEC performance was evaluated using key indicators such as photocurrent density, conversion efficiency, and the number of hydrogen moles. The number of hydrogen moles was quantitatively estimated to be 140.4, 160.2, and 300 µmol/h·g at -1 V for the polymer, copolymer, and polymer blend, respectively, in the presence of APS + FeCl3 as an oxidant. Further, other samples of polymers showed antimicrobial properties against different species of bacteria. Hence, the present study may provide a cost-effective method to produce solar hydrogen fuel from water.

5.
RSC Adv ; 9(39): 22389-22400, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-35519441

RESUMO

Electrodeposition of silver, tin and their alloys from different aqueous electrolytes suffer from various environmental issues and deposits are affected by H2 evolution and metal oxide formation. In this work, these metals and their alloys are electrodeposited by cyclic voltammetry utilizing ionic liquids based on C5H14ClNO (choline chloride) that permits deposit properties control. Both Ag and Sn concentrations in the ionic liquid were varied from 0.01 to 0.15 mol L-1. Methionine effect on the reduction potential of Sn and Ag was studied. Different techniques were applied to explore the structures, morphologies, and electrochemical (EC) activities of the deposits. A single Ag3Sn phase with orthorhombic packed structure was observed for all alloys, whereas the preferred growth orientation was varied from (202) to (112) depending on Ag%. Also, the dislocation density is decreased by increasing Ag content. EDX spectra showed only Ag and Sn signals indicating the high purity of the Sn-Ag alloys. The deposit from Sn-rich liquid showed rougher and larger agglomerates at the surface than that formed from the Ag-rich liquids with or without methionine. The electrochemical activities of the deposits toward the H2 evolution reaction (HER) were investigated through electrochemical polarization (ECP) measurements and EC impedance spectroscopies (EISs). The Sn-Ag alloys possess higher performance, as a catalyst for HER using alkaline solution, than Ag or Sn electrodes. The highest rate of HER was recorded for Sn-35% Ag and Sn-97% Ag deposits, which correlated strongly to the microstructure and surface morphology. The ECP results were confirmed by EIS investigations. The measured impedance values are close-fitting to a hypothetical model for the electrode/electrolyte interface.

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