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The combination of halide perovskite NCs with graphene to design heterostructures has proven to be a promising candidate for energy applications, optoelectronics, and photocatalysis. Efficient light energy absorption in perovskite NC-graphene heterostructures is of fundamental importance owing to their optoelectronic applications. A detailed understanding of the important process for device action, particularly interfacial charge transfer (CT), has thus far lingered subtly. This study describes the influence of the different surface functionalities of graphene on the CT dynamics in FAPbBr3 NCs attached to functionalized graphene heterostructures. Functionalized graphenes i.e., graphene oxide (GO) and amino acids (alanine (Ala), tyrosine (Tyr) and cysteine (Cys)) functionalized GO, were synthesized. By assembling the heterostructures of functionalized graphene with NCs, the quenching of photoluminescence (PL) of the FAPbBr3 NCs was observed. The photo-generated hole transfer from FAPbBr3 to functionalized graphene is responsible for PL quenching, which is supported by time-resolved photoluminescence (TRPL) and cyclic voltammetry (CV) analysis. Our study revealed that the rate of CT and charge transfer efficiency (ECT) strongly depend on the nature of the functionalizing moieties. The highest hole transfer efficiency for NC-functionalized graphene heterostructures was observed in the case of cysteine-functionalized GO (88.84%) and the lowest with GO (38.15%). This suggests that cysteine-functionalized graphene is the best hole acceptor amongst all functionalized graphenes. This study offers a method to regulate energetics and investigate the extent of hole transfer in perovskite NCs and functionalized graphene heterostructures. These findings tend to draw new directions to stimulate advance research regarding the fundamental understanding of hole transfer in surface-modified donor-acceptor heterostructures for light harvesting assemblies, especially solar cells.
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Nanoparticles prepared from bio-reduction agents are of keen interest to researchers around the globe due to their ability to mitigate the harmful effects of chemicals. In this regard, the present study aims to synthesize copper oxide nanoparticles (CuO NPs) by utilizing root extracts of ginger and garlic as reducing agents, followed by the characterization and evaluation of their antimicrobial properties against multiple drug resistant (MDR) S. aureus. In this study, UV-vis spectroscopy revealed a reduced degree of absorption with an increase in the extract amount present in CuO. The maximum absorbance for doped NPs was recorded around 250 nm accompanying redshift. X-ray diffraction analysis revealed the monoclinic crystal phase of the particles. The fabricated NPs exhibited spherical shapes with dense agglomeration when examined with FE-SEM and TEM. The crystallite size measured by using XRD was found to be within a range of 23.38-46.64 nm for ginger-doped CuO and 26-56 nm for garlic-doped CuO. Green synthesized NPs of ginger demonstrated higher bactericidal tendencies against MDR S. aureus. At minimum and maximum concentrations of ginger-doped CuO NPs, substantial inhibition areas for MDR S. aureus were (2.05-3.80 mm) and (3.15-5.65 mm), and they were measured as (1.1-3.55 mm) and (1.25-4.45 mm) for garlic-doped NPs. Conventionally available CuO and crude aqueous extract (CAE) of ginger and garlic roots reduced MB in 12, 21, and 38 min, respectively, in comparison with an efficient (100%) reduction of dye in 1 min and 15 s for ginger and garlic doped CuO NPs.
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Nanopartículas del Metal , Nanopartículas , Zingiber officinale , Animales , Antibacterianos/química , Antibacterianos/farmacología , Bovinos , Cobre/química , Cobre/farmacología , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Nanopartículas/química , Extractos Vegetales/farmacología , Staphylococcus aureusRESUMEN
G-protein-coupled receptors for extracellular nucleotides are known as P2Y receptors and are made up of eight members that are encoded by distinct genes and can be classified into two classes based on their affinity for specific G-proteins. P2Y receptor modulators have been studied extensively, but only a few small-molecule P2Y receptor antagonists have been discovered so far and approved by drug agencies. Derivatives of indole carboxamide have been identified as P2Y12 and P2X7 antagonist, as a result, we developed and tested a series of indole derivatives4a-lhaving thiourea moiety as P2Y receptor antagonist by using a fluorescence-based assay to measure the inhibition of intracellular calcium release in 1321N1 astrocytoma cells that had been stably transfected with the P2Y1, P2Y2, P2Y4 and P2Y6 receptors. Most of the compounds exhibited moderate to excellent inhibition activity against P2Y1 receptor subtype. The series most potent compound, 4h exhibited an IC50 value of 0.36 ± 0.01 µM selectivity against other subtypes of P2Y receptor. To investigate the ligand-receptor interactions, the molecular docking studies were carried out. Compound 4h is the most potent P2Y1 receptor antagonist due to interaction with an important amino acid residue Pro105, in addition to Ile108, Phe119, and Leu102.
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Indometacina/farmacología , Antagonistas Purinérgicos/farmacología , Receptores Purinérgicos/metabolismo , Tiourea/farmacología , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Humanos , Indometacina/síntesis química , Indometacina/química , Estructura Molecular , Antagonistas Purinérgicos/síntesis química , Antagonistas Purinérgicos/química , Relación Estructura-Actividad , Tiourea/químicaRESUMEN
This article describes the design and synthesis of a series of novel amantadine-thiourea conjugates (3a-j) as Jack bean urease inhibitors. The synthesized hybrids were assayed for their in vitro urease inhibition. Accordingly, N-(adamantan-1-ylcarbamothioyl)octanamide (3j) possessing a 7-carbon alkyl chain showed excellent activity with IC50 value 0.0085 ± 0.0011 µM indicating that the long alkyl chain plays a vital role in enzyme inhibition. Whilst N-(adamantan-1-ylcarbamothioyl)-2-chlorobenzamide (3g) possessing a 2-chlorophenyl substitution was the next most efficient compound belonging to the aryl series with IC50 value of 0.0087 ± 0.001 µM. The kinetic mechanism analyzed by Lineweaver-Burk plots revealed the non-competitive mode of inhibition for compound 3j. Moreover, in silico molecular docking against target protein (PDBID 4H9M) indicated that most of the synthesized compounds exhibit good binding affinity with protein. The compound 3j forms two hydrogen bonds with amino acid residue VAL391 having a binding distance of 1.858 Å and 2.240 Å. The interaction of 3j with amino acid residue located outside the catalytic site showed its non-competitive mode of inhibition. Based upon these results, it is anticipated that compound 3j may serve as a lead structure for the design of more potent urease inhibitors.
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Inhibidores Enzimáticos/química , Infecciones por Helicobacter/tratamiento farmacológico , Relación Estructura-Actividad , Ureasa/química , Amantadina/análogos & derivados , Amantadina/química , Amantadina/farmacología , Dominio Catalítico/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/enzimología , Helicobacter pylori/patogenicidad , Humanos , Enlace de Hidrógeno/efectos de los fármacos , Cinética , Simulación del Acoplamiento Molecular , Estructura Molecular , Tiourea/química , Tiourea/farmacología , Ureasa/antagonistas & inhibidoresRESUMEN
A small set of four new fluorenyl chromophores (5-5a-c) was accomplished by stepwise nucleophilic substitution, Friedel-Crafts acylation, Ullman coupling, aldol condensation and cyclization reactions. The fluorene moiety was substituted at 2,7,9 and 9' positions with diverse groups. The synthesized derivatives were characterized by FTIR, 1H-NMR and 13C-NMR spectroscopic techniques. The optical properties were evaluated by by UV-VIS absorption and Fluorescence studies. HOMO and LUMO energy levels were evaluated by electrochemical studies and were found at -5.37-5.83 eV and - 2.47-2.94 eV respectively with band gap energy values 2.88 to 2.91 eV. The band gap energy values suggested that these synthesized molecules can be manipulated in the designing of blue and green OLEDS. Graphical Abstract.
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The present exploration demonstrates the efficient, sustainable, cost-effective, and environment-friendly green approach for the synthesis of silver (Ag)-doped copper oxide (CuO) embedded with reduced graphene oxide (rGO) nanocomposite using the green one-pot method and the green deposition method. Leaf extracts of Ficus carica and Azadirachta indica were used for both methods as reducing and capping agents. The effect of methodology and plant extract was analyzed through different characterization techniques such as UV-visible spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), x-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM). The lowest band gap of 3.0 eV was observed for the Ag/CuO/rGO prepared by the green one-pot method using F. carica. The reduction of graphene oxide (GO) and the formation of metal oxide was confirmed through functional group detection using FT-IR. Calculation of thermodynamic parameters showed that all reactions involved were nonspontaneous and endothermic which shows the stability of nanocomposites. XRD studies revealed the crystallinity, phase purity and small average crystallite size of 32.67 nm. SEM images disclosed that the morphology of the nanocomposites was spherical with agglomeration and rough texture. The particle size of the nanocomposites calculated through HRTEM was found in agreement with the XRD results. The numerous properties of the synthesized nanocomposites enhanced their potential against the degradation of methylene blue, rhodamine B, and ciprofloxacin. The highest percentage degradation of Ag/CuO/rGO was found to be 97%, synthesized using the green one-pot method with F. carica against ciprofloxacin, which might be due to the lowest band gap, delayed electron-hole pair recombination, and large surface area available. The nanocomposites were also tested against the Gram-positive and Gram-negative bacteria. RESEARCH HIGHLIGHTS: Facile synthesis of Ag/CuO/rGO nanocomposite using a green one-pot method and the green deposition method. The lowest band gap of 3.0 eV was observed for nanocomposite prepared by a green one-pot method using Ficus carica. Least average crystallite size of 32.67 nm was found for nanocomposite prepared by a green one-pot method using F. carica. Highest antibacterial and catalytic activity (97%) was obtained against ciprofloxacin with nanocomposite prepared through green one-pot method using F. carica. A mechanism of green synthesis is proposed.
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Azadirachta , Ficus , Grafito , Nanopartículas del Metal , Nanocompuestos , Antibacterianos/farmacología , Antibacterianos/química , Espectroscopía Infrarroja por Transformada de Fourier , Bacterias Gramnegativas , Bacterias Grampositivas , Nanocompuestos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Ciprofloxacina , Nanopartículas del Metal/químicaRESUMEN
Solar-driven desalination is considered an alternative to the conventional desalination due to its nearly zero carbon footprint and ease of operating in remote areas. Water can be purified wherever sunlight is available, providing a viable solution to water shortage. Metal chalcogenide-based materials are revolutionary for solar evaporators due to their excellent photothermal conversion efficiency, facile synthesis methods, stability, and low cost. Herein we present a prototype Bi-doped CoTe nano-solar evaporator embedded on leno weave cotton gauze (Bi/CoTe@CG) using the sonication process. The nano-solar evaporator was synthesized using a simple hydrothermal approach to provide an opportunity to scale up. The as designed solar evaporator consisting of 5 % Bi/CoTe@CG showed an excellent water flux of 2.38 kg m-2 h-1 upon one sun radiation (1 kW m-2), considered among the highest literature-reported values. The introduced solar evaporator showed excellent solar efficiency of 96.7 %, good stability, and reusability for five cycles of one hour. The best doping ratio of Bi in CoTe was obtained as Bi0.5Co9.5Te with a contact angle of 11.9° in powder form. The hydrophilic nature of the designed solar-evaporator increased the water interaction with the embedded nano-solar evaporator, which helps the transfer of the heat to nearby water molecules, break their hydrogen bonding and increase the evaporation rate. The ion concentration, of the desalinated pure water collected using Bi/CoTe@CG, decreased by many orders of magnitude and it is far below the limit of WHO standards for Na+ and K+. Thus, a self-floating Bi-doped CoTe nano-solar evaporator deposited on cotton gauze (CG) is an excellent solar evaporator for seawater desalination. The proposed solar evaporator is another step towards introducing environmentally friendly desalination methods.
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Surface active amine-functionalized silica coated magnetic iron oxide nanoparticles were prepared by a simple two-step process for adsorbing CO2 gas from aqueous medium. First, oleic acid (OA) coated iron oxide magnetic particles (denoted as Fe3O4-OA) were prepared by a simple coprecipitation method. Then, the surface of the Fe3O4-OA particles was coated with silica by using tetraethyl orthosilicate. Finally, aminated Fe3O4/SiO2-NH2 nanoparticles were concomitantly formed by the reactions of 3-aminopropyl triethoxysilane with silica-coated particles. The formation of materials was confirmed by Fourier transform infrared spectral analysis. Transmission electron microscopic analysis revealed both spherical and needle-shaped morphologies of magnetic Fe3O4/SiO2-NH2 particles with an average size of 15 and 68.6 nm, respectively. The saturation magnetization of Fe3O4/SiO2-NH2 nanoparticles was found to be 33.6 emu g-1, measured by a vibrating sample magnetometer at ambient conditions. The crystallinity and average crystallite size (7.0 nm) of the Fe3O4/SiO2-NH2 particles were revealed from X-ray diffraction data analyses. Thermogravimetric analysis exhibited good thermal stability of the nanoadsorbent up to an elevated temperature. Zeta potential measurements revealed pH-sensitive surface activity of Fe3O4/SiO2-NH2 nanoparticles in aqueous medium. The produced magnetic Fe3O4/SiO2-NH2 nanoparticles also exhibited efficient proton capturing activity (92%). The particles were used for magnetically recyclable adsorption of aqueous CO2 at different pH values and temperatures. Fe3O4/SiO2-NH2 nanoparticles demonstrated the highest aqueous CO2 adsorption efficiency (90%) at 40 °C, which is clearly two times higher than that of nonfunctionalized Fe3O4-OA particles.
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In this study, nickel selenide (NiSe), Ag/C3N4-NiSe, and C3N4/Ag-NiSe nanowires (NWs) were synthesized via coprecipitation. The prepared NWs were employed for the degradation of the rhodamine B (RhB) dye in the absence of light using sodium borohydride (NaBH4), bactericidal activity against pathogenic Staphylococcus aureus (S. aureus) and in silico docking study to investigate the d-alanine ligase (DDl) and deoxyribonucleic acid (DNA) gyrase of S. aureus. NWs demonstrate a catalytic degradation efficiency of 69.58% toward RhB in a basic medium. The percentage efficacy of the synthesized materials was evaluated as 19.12-42.62% at low and 36.61-49.72% at high concentrations against pathogenic S. aureus. Molecular docking results suggest that both C3N4/Ag-doped NiSe and Ag/C3N4-doped NiSe possess inhibitory activities toward DDl and DNA gyrase of S. aureus, which coincides with the in vitro bactericidal activity. Based on the research outcomes, the synthesized NWs show potential as an effective agent for water purification and resistance to microbial contaminants.
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Different concentrations of zirconium with a fixed quantity (4 wt%) of chitosan (CS) doped nickel cobaltite (NiCo2O4) nanorods were synthesized using a co-precipitation approach. This cutting-edge research explores the cooperative effect of Zr-doped CS-NiCo2O4 to degrade the Eriochrome black T (EBT) and investigates potent antibacterial activity against Staphylococcus aureus (S. aureus). Advanced characterization techniques were conducted to analyze structural textures, morphological analysis, and optical characteristics of synthesized materials. XRD pattern unveiled the spinal cubic structure of NiCo2O4, incorporating Zr and CS peak shifted to a lower 2θ value. UV-Vis spectroscopy revealed the absorption range increased with CS and the same trend was observed upon Zr, showing a decrease in bandgap energy (Eg) from 2.55 to 2.4 eV. The optimal photocatalytic efficacy of doped NiCo2O4 within the basic medium was around 96.26 %, and bactericidal efficacy was examined against S. aureus, revealing a remarkable inhibition zone (5.95 mm).
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Antibacterianos , Quitosano , Colorantes , Nanotubos , Staphylococcus aureus , Circonio , Quitosano/química , Quitosano/farmacología , Circonio/química , Circonio/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Nanotubos/química , Colorantes/química , Níquel/química , Cobalto/química , Pruebas de Sensibilidad Microbiana , Compuestos Azo/químicaRESUMEN
A coprecipitation approach was employed to synthesize aluminum oxide (Al2O3) with a fixed quantity of graphitic carbon nitride (g-C3N4) and various concentrations of Mg (2 and 4 wt. %). The main objective of this research is to explore and enhance the dye degradation potential and antimicrobial efficacy of synthesized pristine and doped Al2O3 with molecular docking analysis. Al2O3 has potent mechanical, thermal, antimicrobial, phosphoric, optical, and electrical properties, but it leaches into water and has a high band gap and low refractive index. g-C3N4 was incorporated into Al2O3 to increase the degradation potency. The incorporation of Mg enhances the metal oxide characteristics and performance in catalysis. XRD patterns revealed the orthorhombic phase of Al2O3. The SAED pattern of Al2O3 and (2 and 4 wt %) Mg/g-C3N4-Al2O3 nanostructures (NSs) showed bright polycrystalline rings. UV-visible spectra showed the absorption of Al2O3 at 289 nm, and upon doping, a blue shift was accompanied. The EDS spectra indicated the existence of Al, O, Na, and Mg, thereby verifying the elemental composition of the pristine and doped samples. TEM images revealed the nanowires (NWs) of Al2O3. The NSs demonstrated outstanding catalytic performance for the remediation of RhB dye in a basic medium of around 97.36%. Mg/g-C3N4-Al2O3 (4 wt %) exhibited a notable augmentation in the inhibition zone, measuring 5.25 mm, when exposed to high-level doses against Staphylococcus aureus. In silico predictions have recently shed light on the underlying mystery of the bactericidal actions of these doped NSs against specific enzyme targets such as DNA gyraseS. aureus.
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Zn-Fe layered double hydroxide (LDH) was synthesized through the low-temperature-based coprecipitation method. Various concentrations of Ag (1, 3, and 5 wt %) with a fixed amount (5 wt %) of polyvinylpyrrolidone (PVP) were doped into LDH nanocomposites. This research aims to improve the bactericidal properties and catalytic activities of doping-dependent nanocomposites. Adding Ag and PVP to LDH enhanced oxygen vacancies, which increased the amount of hydroxide adsorption sites and the number of active sites. The doped LDH was employed to degrade rhodamine-B dye in the presence of a reducing agent (NaBH4), and the obtained results showed maximum dye degradation in a basic medium compared to acidic and neutral. The bactericidal efficacy of doped Zn-Fe (5 wt %) showed a considerably greater inhibition zone of 3.65 mm against Gram-negative (G-ve) or Escherichia coli (E. coli). Furthermore, molecular docking was used to decipher the mystery behind the microbicidal action of Ag-doped PVP/Zn-Fe LDH and to propose an inhibition mechanism of ß-ketoacyl-acyl carrier protein synthase IIE. coli (FabH) and deoxyribonucleic acid gyrase E. coli behind in vitro results.
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Doping conventional materials with a second element is an exciting strategy for enhancing catalytic performance via electronic structure modifications. Herein, Mn-doped CdS thin films were successfully synthesized with the aid of the chemical bath deposition (CBD) by varying the pH value (8, 10, and 12) and the surfactant amount (20, 40, 60â mg). Different morphologies like nano-cubes, nanoflakes, nano-worms, and nanosheets were obtained under different deposition conditions. The optimized Mn-doped CdS synthesized at pH=8 exhibited better photoelectrochemical (PEC) performance for oxygen evolution reaction (OER) than pure CdS films, with a maximum photocurrent density of 300â µA/cm2 at an external potential of 0.5â V, under sunlight illumination. The observed performance is attributed to the successful Mn doping, porosity, high surface area, and nanosphere morphology.
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The harmful cationic dyes present in industrial waste significantly decrease the effectiveness of remedy operations. Considering the horrendous impact of these dyes on the environment and biodiversity, silver bromide (AgBr) and chitosan (CS) doped copper ferrite (CuFe2O4) nanostructures (NSs) were prepared by the co-precipitation route. In this work, The surface characteristics of CuFe2O4 can be altered by CS, potentially enhancing its catalytic reaction compatibility. The functional groups in CS interact with the surface of CuFe2O4, influencing its catalytic behavior. AgBr can have an impact on the dynamics of charge carriers in the composite. Better charge separation and transfer which is essential for catalytic processes. The catalytic degradation of RhB was significantly enhanced (100 %) using 4 wt% of AgBr-doped CS-CuFe2O4 catalysts in a basic medium. The significant inhibitory zones (9.25 to 17.95 mm) inhibitory in maximum doses were seen against Gram-positive bacteria (S. aureus). The bactericidal action of AgBr/CS-doped CuFe2O4 NSs against DNA gyraseS.aureus and tyrosyl-tRNAsynthetase S. aureus was rationalized using molecular docking studies, which supported their function as inhibitors.
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Quitosano , Simulación del Acoplamiento Molecular , Rodaminas , Staphylococcus aureus , ColorantesRESUMEN
Co-precipitation method was adopted to synthesize ternary heterostructure catalysts La/CS-CoSe NSs (lanthanum/chitosancobalt selenide nanostructures) without the use of a surfactant. During synthesis, a fixed amount (3 wt%) of CS was doped with 2 and 4 wt% La to control the growth, recombination rate and stability of CoSe NSs. The doped samples served to enhance the surface area, porosity and active sites for catalytic degradation of rhodamine B dye and antibacterial potential against Staphylococcus aureus (S. aureus). Additionally, the synthesized catalysts were examined for morphological, structural and optical characteristics to assess the influence of dopants to CoSe. XRD spectra verified the hexagonal and cubic structure of CoSe, whereas the porosity of the undoped sample (CoSe) increased from 45 to 60 % upon incorporation of dopants (La and Cs). Among the samples analyzed during this study, 4 % La/CS-CoSe exhibited significant bactericidal behavior as well as the highest catalytic reduction of rhodamine B dye in a neutral environment. Molecular docking analysis was employed to elucidate the underlying mechanism behind the bactericidal activity exhibited by CS-CoSe and La/CS-CoSe NSs against DHFRS. aureus and DNA gyraseS. aureus.
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Quitosano , Nanoestructuras , Simulación del Acoplamiento Molecular , Staphylococcus aureus , Antibacterianos/farmacología , CobaltoRESUMEN
Presently, there is considerable emphasis on biological synthesis of nanoparticles containing bioactive reducing compounds with an aim to mitigate the harmful effects of pollutants. The approach under study is simple and ideal for the production of durable antimicrobial nanomaterials by novel single-step green synthesis of TiO2 metal oxide nanostructures using ginger and garlic crude aqueous extracts with bactericidal and catalytic activity. A variety of experimental techniques were used to characterize the synthesized nanomaterials. As demonstrated using x-ray diffraction and ultra-violet visible spectroscopy, the produced nanoparticles exhibited high absorption at 318 nm with size varying between 23.38 nm for ginger and 58.64 nm for garlic in biologically-reduced TiO2. At increasing concentrations (500, 1000 µg/50 µl), nanoparticles reduced with garlic exhibited enhanced bactericidal efficacy against multiple drug-resistant S. aureus and effectively decomposed toxic methylene blue (MB) dye. In conclusion, biologically-reduced TiO2 nanoparticles may prove an effective tool in the fight against microbial illnesses and drug resistance.
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Mastitis Bovina , Nanopartículas del Metal , Staphylococcus aureus Resistente a Meticilina , Animales , Femenino , Bovinos , Staphylococcus aureus , Nanopartículas del Metal/química , Mastitis Bovina/tratamiento farmacológico , Antibacterianos/química , Difracción de Rayos X , Extractos Vegetales/farmacología , Extractos Vegetales/química , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
In this research, hydrothermally synthesized tungsten trioxide (WO3) nanocomposites doped polyvinylpyrrolidone (PVP) and chitosan (CS) were studied. Various concentrations (3, 6, and 9 wt%) of PVP were doped into a fixed amount of binary system (CS-WO3) nanocomposites. PVP/CS polymers showed attractive attention because of their different structure, functionality, and architecture control as dopant to WO3. The PVP/CS encapsulates the WO3 (ternary composite), which controls crystallite size (band gap reduction), rapidly overcomes the recombination electron-hole pairs issues, and generates the active sites, resulting in improved catalytic and antimicrobial activity. The synthesized nanocomposites revealed significant catalytic efficiency and methylene blue (MB) dye depletion of 99.9 % in the presence of reducing agent (NaBH4) in neutral and acidic media. Antimicrobial effectiveness of produced nanostructures towards Escherichia coli (E. coli) pathogen at low and high concentrations were investigated by Vernier caliper in mm. Furthermore, to their microbicidal action, docking experiments of CS-doped WO3 and PVP/CS-doped WO3 nanostructures for DHFR and FabI of Escherichia coli suggested blockage of aforesaid enzymes as the plausible pathway.
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Antiinfecciosos , Quitosano , Nanocompuestos , Povidona , Escherichia coli , Tungsteno/químicaRESUMEN
Generating highly dispersed metal NPs of the desired size on surfaces such as porous silica is challenging due to wettability issues. Here, we report highly active and well-dispersed Pd incorporated mesoporous MCM-41 (Pd@MCM) using a facile impregnation via a molecular approach based on hydrogen bonding interaction of a palladium ß-diketone complex with surface silanol groups of mesoporous silica. Controlled thermal treatment of so obtained materials in air, argon, and hydrogen provided the catalysts characterized by electron microscopy, nitrogen physisorption, X-ray diffraction and spectroscopy. Gratifyingly, our catalyst provided the lowest ever activation energy (14.3â kJ/mol) reported in literature for dehydrogenation of NaBH4 . Moreover, the rate constant (7×10-3 â s-1 ) for the reduction of 4-nitrophenol outperformed the activity of commercial Pd/C (4×10-3 â s-1 ) and Pd/Al2 O3 (5×10-3 â s-1 ) catalysts.
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The removal of cationic dyes from water has received a great attention of researchers considering their influence on environment and ecosystem. In current work, starch-grafted-poly acrylic acid (St-g-PAA) doped BaO nanostrucutures have been synthesized by co-precipitation approach. The aim of this research was to reduce the harmful methylene blue dye and evaluate the antibacterial activity of St-g-PAA doped BaO. XRD spectra exhibited the tetragonal structure of BaO and no variations occurred upon doping. The optical properties of St-g-PAA doped BaO have been evaluated by UV-Vis spectrophotometer. The existence of a dopant in the product was verified using EDS spectroscopy. TEM revealed the formation of cubic-shaped NPs of BaO and upon the addition of St-g-PAA, a few nanorod-like structures. The higher concentration of St-g-PAA doped BaO exhibit a remarkable reduction of methylene blue in a basic environment. Furthermore, St-g-PAA doped BaO revealed higher antimicrobial efficacy against Staphylococcus aureus in comparison to Escherichia coli. In silico studies were conducted against enoyl-[acylcarrier-protein] reductase (FabI) and beta-lactamase enzyme to evaluate the potential of both St-g-PAA and St-g-PAA doped BaO nanocomposites as their inhibitors and to rationalize their possible mode of action.
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Antiinfecciosos , Nanocompuestos , Simulación del Acoplamiento Molecular , Almidón/química , Azul de Metileno/química , Ecosistema , Antiinfecciosos/farmacología , Escherichia coliRESUMEN
Different concentrations (2 and 4 wt%) of graphite carbon nitride (g-C3N4) was doped into fixed amount of chitosan (CS) and nickel oxide (NiO) nanoparticles (NPs) via a co-precipitation route. The aim of study is to remove the pollutants from wastewater through catalytic activity (CA) and determine the bactericidal activities of synthesized products. X-ray diffraction pattern confirmed the cubic structure of NiO NPs and peak shifted to higher angle upon g-C3N4 doping. Fourier transform infrared spectroscopy revealed the existence of bending and stretching vibration mode. The absorption decreased gradually accompanied blue-shift and assessed bandgap energy increased upon doping. The high resolution transmission electron microscopy micrographs confirmed the formation of cubic-shaped NPs and elongated nanorods were seen for NiO and co-doped NiO. The catalytic efficiency of samples was examined using methylene blue (MB) in the presence of reducing agent. A remarkable dye de-colorization was confirmed with a g-C3N4 and CS doping; moreover, the bactericidal efficacy compared to Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was observed as 3.15 and 13.8 mm, respectively. In silico, molecular docking investigations targeting against b-lactamaseS. aureus and FabHE. coli enzymes assisted to elaborate the mechanism underlying microbicidal action of the NPs.