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1.
ACS Omega ; 9(5): 5386-5394, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38343948

RESUMO

The present study described the construction and the electrochemical futures of a novel inject-printed electrochemical sensor based on spinel ferrite-doped manganese oxide nanoparticles (FMnONPs) for the sensitive differential pulse voltammetric quantification of brimonidine (BRIM) in ophthalmic solutions. At the optimized electroanalytical parameters, calibration graphs were linear within the BRIM concentration range of 24-3512 ng mL-1 and recorded a detection limit value of 8.21 ng mL-1. Cyclic voltammograms recorded at different scan rates indicated an adsorption-reaction mechanism for the electrooxidation of BRIM at the electrode surface with the involvement of two electrons and one proton based on the oxidation of the five-membered ring nitrogen atom as recommended by the molecular orbital calculations. The enhanced performance of the introduced inkjet-printed sensors integrated with FMnONPs encourages their application for monitoring BRIM residues in ophthalmic solutions and biological fluids in the presence of BRIM degradation products and other interferents for diverse quality control applications.

2.
Heliyon ; 9(10): e21015, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37867880

RESUMO

By combining hydrazide with 2-Acetylpyridine, a hydrazone ligand (HL) was successfully created. Several copper (II) salts have been used to create three copper (II) hydrazone complexes (acetate, sulphate, and chloride). The hydrazide ligand and its copper (II) complexes (1-3) were studied via variety of analytical techniques, including elemental analysis, electronic, infrared, UV-vis Spectrum, XRD study, thermal analysis, also molar conductivity amounts. The spectrum results indicate that in all complexes, the ligand exhibits monobasic tridentate behavior. Octahedral geometries were present in all metal complexes. The Coats-Redfern equations were used to compute and describe the dynamics properties of several steps of TGA (Ea, A, ΔH*, ΔS*, and ΔG*). Calculations using the density functional theory (DFT) were done at the molecular studio software toward examine ligands agent's and its complexes' best structures. The MCF-7 in addition to HepG-2 cell lines was resistant to tumor-inducing effects of the copper (II) chelates. The in vitro antioxidant capacities of all complexes have been estimated via DPPH free radical scavenger assays. Furthermore, zones of inhibition length accustomed to test antimicrobial effect of particular complexes in vitro towards Staphylococcus aureus (Gram positive bacteria) E. coli (Gram negative bacteria). Both absorption spectra and viscosity measurements in calf thymus DNA binding have been used to study the complexes. In order to explore docking research of copper (II) chelates, the crystallographic construction of the SARS-active CoV-2's site protein (PDB ID:6XBH) was used (COVID-19) and breast cancer distorted (PDB ID: 3hb5).

3.
ACS Omega ; 8(35): 32130-32145, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37692223

RESUMO

Eliminating pesticides is essential for lowering the dangers to our environment. To do this effectively, it is crucial to find adsorbents with remarkable adsorption capacities, easy retrieval, and separation. Metal-organic frameworks (MOFs) have been extensively recognized for their exceptional ability to absorb pollutants. Therefore, we used novel lanthanum metal-organic frameworks (La-MOFs) to eliminate deltamethrin (DEL) from aqueous solutions. We proved through experimentation that the La-MOF is an efficient adsorbent for DEL from water. A study of the material revealed that the adsorbent had a surface area of 952.96 m2 per gram and a pore volume of 1.038 cm3/g. These outcomes show how this substance can absorb particles. Utilizing kinetic models and conforming to the pseudo-second-order model, a thorough analysis of the efficiency of DEL adsorption onto La-MOF was conducted. To create a perfectly tailored approach, we utilized many parameters. The synthetic La-MOF adsorbent may undergo up to five steps of adsorption-desorption and has exceptional cyclability and reusability. To confirm purifying wastewater samples in the laboratory, the presentation of the established adsorbent was evaluated. For the management of industrial effluent and water filtration, the La-MOF adsorbent offered a simple and effective solution. Our investigation suggests that the method we describe for removing DEL from wastewater samples using the La-MOF adsorbent is unique.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 122986, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37336189

RESUMO

Electrospun glass nanofibers (GNFs) were used to strengthen polycarbonate (PC) to create long-persistent photoluminescent and fluorescent smart materials such as afterglow concrete and smart window. Physical integration of lanthanide-activated aluminate (LA) nanoparticles (NPs) yielded transparent GNFs@PC smart sheets. Spectral investigations utilizing photoluminescence and CIE Lab parameters were performed to confirm that the translucent appearance of GNFs@PC changed to green when exposed to UV light. This fluorescence activity was quickly reversible for the GNFs@PC hybrids with low concentrations of LANPs, which indicate fluorescence emission. Higher phosphor concentrations in GNFs@PC led to longer-lasting afterglow photoluminescence and slower reversibility. The GNFs@PC hybrids showed an emission band detected at 518 nm upon excitation at 368 nm. The morphological characteristics of LANPs and GNFs were analyzed by transmission electron microscopy (TEM), which revealed sizes of 11-26 nm and 250-300 nm, respectively. GNFs were prepared using electrospinning technology and then used as a roughening agent into PC sheets. Morphological characteristics of GNFs and GNFs@PC smart sheets were examined using energy-dispersive X-ray spectroscopy (EDXA), X-ray fluorescence (XRF) and scanning electron microscopy (SEM). The GNFs@PC smart sheets were shown to have enhanced scratch resistance in comparison to LANPs-free PC control sample. Increases in LANPs concentration enhanced both hydrophobicity and UV protection.

5.
Environ Technol ; : 1-20, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37248830

RESUMO

In the current investigation, we have reported on the preparation of Na-Mordenite (MOR) modified by tryptophan (MOR-NH2) nanocomposite was synthesized and characterized using FT-IR, XRD, SEM, XPS, and BET that represented that the MOR-NH2 has high surface area 288 m2/g and pore volume 0.38 cm3/g. This composite represented high efficiency in removal of food dye Azorubine (E122) was 1043 mg/g. Study all the factors that affected on the adsorption such as pH, dose, salinity, E122 dye concentration as well as study the adsorption isotherm models that represented that was fitted to Langmuir. Moreover, study the effect of time according to it the adsorption process was fitted to Pseudo-second-order, and the effect of temperature that approved that the reaction was endothermic, spontaneous, and chemisorption process. The MOR-NH2 nanocomposite was tested and proven to effectively inhibit the growth of Escherichia coli ATCC® 25922™ and Staphylococcus aureus ATCC® 25923™ at low concentrations. To the best of our knowledge, this work is the first to report the usage of MOR-NH2 adsorbents for the removal of E122 dye in wastewater samples. The mechanism of interaction between MOR-NH2 and E122 dye was determining as it could be through Hydrogen bonding, pore filling, or through π-π interaction. This research offers a promising solution for purifying water sources that are contaminated with a variety of chemicals, microorganisms, and other contaminants.

6.
Membranes (Basel) ; 12(8)2022 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35893450

RESUMO

Zinc oxide thin film (ZnO thin film) and a silver-doped zinc oxide nanocomposite thin film (Ag/ZnO thin film) were prepared by the technique of the pulsed laser deposition at 600 °C to be applicable as a portable catalytic material for the removal of 4-nitrophenol. The nanocomposite was prepared by making the deposition of the two targets (Zn and Ag), and it was analyzed by different techniques. According to the XRD pattern, the hexagonal wurtzite crystalline form of Ag-doped ZnO NPs suggested that the samples were polycrystalline. Additionally, the shifting of the diffraction peaks to the higher angles, which denotes that doping reduces the crystallite size, illustrated the typical effect of the dopant Ag nanostructure on the ZnO thin film, which has an ionic radius less than the host cation. From SEM images, Ag-doping drastically altered the morphological characteristics and reduced the aggregation. Additionally, its energy band gap decreased when Ag was incorporated. UV spectroscopy was then used to monitor the catalysis process, and Ag/ZnO thin films had a larger first-order rate constant of the catalytic reaction K than that of ZnO thin film. According to the catalytic experiment results, the Ag/ZnO thin film has remarkable potential for use in environmentally-favorable applications.

7.
Membranes (Basel) ; 12(7)2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35877862

RESUMO

Al2O3-poly(vinyl alcohol) nanocomposite (Al2O3-PVA nanocomposite) was generated in a single step using an eco-friendly method based on the pulsed laser ablation approach immersed in PVA solution to be applicable for the removal of Ni(II) from aqueous solution, followed by making a physicochemical characterization by SEM, XRD, FT-IR, and EDX. After that, the effect of adsorption parameters, such as pH, contact time, initial concentration of Ni(II), and medium temperature, were investigated for removal Ni(II) ions. The results showed that the adsorption was increased when pH was 5.3, and the process was initially relatively quick, with maximum adsorption detected within 90 min of contact time with the endothermic sorption process. Moreover, the pseudo-second-order rate kinetics (k2 = 9.9 × 10-4 g mg-1 min-1) exhibited greater agreement than that of the pseudo-first-order. For that, the Ni(II) was effectively collected by Al2O3-PVA nanocomposite prepared by an eco-friendly and simple method for the production of clean water to protect public health.

8.
Polymers (Basel) ; 14(3)2022 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-35160446

RESUMO

Herein, a new homologues series of fluorinated liquid crystal compounds, In, 4-(((4-fluorophenyl)imino)methyl)-2-methoxyphenyl 4-alkoxybenzoate were synthesized and its mesomorphic properties were investigated both experimentally and theoretically. The synthesized compounds were characterized by elemental analyzer, NMR, and FT-IR spectroscopy to deduce the molecular structures. The differential scanning calorimetry was employed to examine mesophase transitions whereas the polarized optical microscopy was used to identify the mesophases. The obtained results revealed that the purely nematic phase observed in all terminal side chains. All homologues showed to possess monotropic nematic mesophases except the derivative I8 exhibits enantiotropic property. The optimized geometrical structures of the present designed groups have been derived theoretically. The experimental data was explained using density functional theory computations. The estimated values of dipole moment, polarizability, thermal energy, and molecule electrostatic potential demonstrated that the mesophase stability and type could be illustrated. Binary phase diagram was constructed and addressed in terms of the mesomorphic temperature range and obtained polymorphic phases. It was found that incorporation of the terminal F-atom and lateral CH3O group influence both conformation and steric effect in pure and mixed states. The absorption and fluorescence emission spectra of fabricated films were recorded to elucidate the impact of terminal side chain on photophysical properties of synthesized liquid crystal. It was noted that the increase of terminal side chain length lead to reduction of optical band gap, whereas charge carrier lifetime increases.

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