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In this study, tin dioxide nanoparticles (SnO2 NPs) were successfully synthesized through an eco-friendly method using basil leaves extract. The fabricated SnO2 NPs demonstrated significant adsorption capabilities for phenol (PHE), p-nitrophenol (P-NP), and p-methoxyphenol (P-MP) from water matrices. Optimal conditions for maximum removal efficiency was determined for each phenolic compound, with PHE showing a remarkable 95% removal at a 3 ppm, 0.20 g of SnO2 NPs, pH 8, and 30 min of agitation at 35 °C. Molecular docking studies unveiled a potential anticancer mechanism, indicating the ability of SnO2 NPs to interact with the epidermal growth factor receptor tyrosine kinase domain and inhibit its activity. The adsorption processes followed pseudo-second order kinetics and Temkin isotherm model, revealing spontaneous, exothermic, and chemisorption-controlled mechanisms. This eco-friendly approach utilizing plant extracts was considered as a valuable tool for nano-sorbent production. The SnO2 NPs not only exhibit promise in water treatment and also demonstrate potential applications in cancer therapy. Characterization techniques including scanning electron microscopy, UV-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy (XRD), and energy-dispersive X-ray spectroscopy (EDAX) provided comprehensive insights into the results.
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Nanopartículas , Estanho , Simulação de Acoplamento Molecular , Óxidos , Nanopartículas/química , Fenol , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Extratos Vegetais/químicaRESUMO
In this work, we presented a synthesis of a composite based on HAp and PEG 6000 using a new method of synthesis dissolution precipitation to be applied for application of wastewater purification from toxic metal ions. Multiple characterization methods were used to analyze the morphology and the structure of the well-prepared compounds including FT-IR, Raman, XRD, XPS, TGA and SEM were used to conduct a composite analysis. The adsorption effectiveness of this analysis towards Pb2+ and various other hazardous metal ions found in sewage was assessed. Batch experiments were conducted to optimize the various operational parameters including adsorbent dose, temperature, pH, contact time, and initial concentration. The Langmuir isotherm was used to fit the data, and it predicted monolayer adsorption with a maximum capacity of 67 mg g-1 for HAP PEG600 and 60 mg g-1 for HAp. A pseudo-second-order equation fits the adsorption process well (0.961-0.971). The thermodynamic data support the spontaneous metal bonding to the composite receptor sites. Theoretical calculations showed that the interaction strength is very strong and gets stronger when the PEG6000 is deprotonated. The results presented here are supported by evidence acquired from experiments. Theoretical computation using Monte Carlo (MC) and Molecular Dynamic (MD) simulation models showed excellent affinity of prepared foams for the model ion Pb2+ with highly negative adsorption energy values indicating vigorous interactions of Pb2+ with the adsorbate surfaces.
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In this study, we report the first total hemisynthesis of trans-himachalol sesquiterpene, a stereoisomer of the natural cis-himachalol isolated from Cedrus atlantica essential oils, from himachalenes mixture in five steps. Reactions conditions were optimized and structures of the obtained compounds were confirmed by IR, mass spectra, 1H, and 13C NMR. The synthesized compounds were investigated for potential activities on various isolated smooth muscles and against different neurotransmitters using molecular docking. The results show that the synthesized compounds display high affinities towards the active site of the protein 7B2W and the compounds exhibit promising activities on various isolated smooth muscles and against different neurotransmitters.
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Sesquiterpenos , Simulação de Acoplamento Molecular , Sesquiterpenos/farmacologia , NeurotransmissoresRESUMO
New cellulose carbamates and cellulose acetate carbamates were prepared by classical addition reaction of isocyanates with alcohols. A Telomerization technique was used to make the grafted molecules strongly anchored and more hydrophobic. These molecules were grafted into cellulose and CA chains, respectively. The structures of the synthesized derivatives were confirmed using Nuclear Magnetic Resonance Spectroscopy, Fourier Transform Infrared and Thermogravimetric Analysis, and their solubility phenomenon was also established, and the carbamate derivatives showed better solubility compared to cellulose. Their ability to biodegrade was investigated, and it was concluded that Cell-P1 and CA-P1 derivatives are more biodegradable than the other samples. These results suggest that the resulting compounds can be used effectively in many useful industrial fields, for instance, eco-friendly food packaging, domains that use materials that are environmentally friendly and sustainable and the development of green chemistry.
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Carbamatos , Celulose , Biodegradação Ambiental , Solubilidade , Celulose/química , Carbamatos/química , Polímeros , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Hydroxyapatite (HAp) attracts interest as a biomaterial for use in bone substitution or allografts. In the current work, biomaterial nanocomposites based on HAp and pectin were synthesized by using the double decomposition method, which involved using pectin extracted from fresh cladodes of the prickly pear, Opuntia ficus-indica. The crystallinity, purity, and several analytical techniques like Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy were used to understand the surface's shape. The results revealed that the produced HAp/pectin nanoparticles are pure, spherical, and amorphous. The spectroscopic data indicated a substantial interaction between HAp and pectin, specifically between Ca (II) and pectin hydroxyl and carboxyl groups. The presence of pectin showed a noticeable influence on the prepared nanocomposite texture and porosity. We further assess the antibacterial and antifungal activity of the developed nanocomposite against a number of pathogenic bacteria and fungi, evaluated by the well diffusion method. In the absence of pectin, the XRD analysis revealed that the HAp nanoparticles had 10.93% crystallinity. When the pectin concentration reached 10 wt.%, it was reduced to approximately 7.29%. All synthesized nanocomposites demonstrated strong antimicrobial activity against both Gram-positive (Staphylococcus aureus and Bacillus cereus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria in addition to various fungi (e.g., Aspergillus fumigatus, Penicillium funiculosum, and Trichoderma viride). This study endorses the HAp/Pectin nanocomposite as an efficient antimicrobial material for biomedical advanced applications.
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Iron phosphate, Fe2 (HPO4)3*4H2O, is synthesized at ambient temperature, using the inorganic sol-gel method coupled to the microwave route. The experimental conditions for the gelling of Fe (III)-H3PO4 system are previously defined. Potentiometric Time Titration (PTT) and Potentiometric Mass Titration (PMT) investigate the acid-base surface chemistry of obtained phosphate. Variations of surface charge with the contact time, Q a function of T, are examined for time contact varying in the range 0-72 h. The mass suspensions used for this purpose are 0.75, 1.25 and 2.5 g L-1. The point of zero charge (PZC) and isoelectric point (IEP) are defined using the derivative method examining the variations [Formula: see text], at lower contact time. A shift is observed for PZC and IEP towards low values that are found to be 2.2 ± 0.2 and 1.8 ± 0.1, respectively. In acidic conditions, the surface charge behavior of synthesized phosphate is dominated by [Formula: see text] group which pKa = 2.45 ± 0.15. Q against T titration method is performed for synthesized Fe2 (HPO4)3*4H2O in NaCl electrolytes. The maximal surface charge (Q) is achieved at the low solid suspension. Hence, for m = 0.75 g L-1, Q value of 50 coulombs is carried at µ = 0.1 and pH around 12, while charge value around 22 coulombs is reached in the pH range: 3-10. The effect of activation time, Q and pH on sodium insertion in iron phosphate, were fully evaluated. To determine the optimal conditions of the studied process, mathematical models are used develop response surfaces in order to characterize the most significant sodium interactions according to the variation of the pH, Q, the contact time and the contents of the synthesized material.
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Natural based composites of hydroxyapatite/Gum Arabic designed for removal of toxic metal arsenic (III) from waste water were synthesized and evaluated. Several composites with various compositions were prepared by the wet chemical method and analyzed using various spectroscopic and analytical methods such as: Fourier transform infrared spectroscopy, total organic carbon production, XRD analysis and scanning electron microscope. The rates of weight loss and water absorption of the HAp/GA composites as a function of time were evaluated in phosphate-buffered saline solution at 37 °C and a pH of 7.4. The effects of several variables on adsorption of arsenic (III) by HAp/GA composites were evaluated. The variables include arsenic (III) concentration, contact time (t) and complex surface nature of HAp/GA composite. Three surface complexation models were used to study the mechanisms controlled the adsorption. The models were Langmuir, Freundlich and Dubinin Radushkevich. The adsorption kinetic of arsenic (III) on the composite surface was described by three modes: pseudo first order, pseudo second order and the intra particle diffusion. The results revealed that, the rate of adsorption of arsenic (III) by HAp/GA composites was controlled by two main factors: the initial concentration of arsenic (III) and the contact time. The kinetic studies also showed that, the rate of adsorption is a second order. The results indicate that, composite offered in this study could be a valuable tool for removing toxic metals for contaminated water by adsorption. Graphical abstract .
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Development of a cost-effective technology for extraction and quantification of carcinogenic and toxic organic materials which are widely used in the industry are critical to humans. Membrane technology received much attention and has already been widely used in this area. In this work, we offer a newly developed bio-based nanocomposite membrane for removal of bisphenol-A (BPA) from water. Three natural components hydroxyapatite (HAp), carboxymethyl cellulose and lysine as a diluent were used for making the bio-based membrane. The membrane was fabricated by two different methods, the conventional casting method and the double decomposition method. Analysis and testing results showed that, membrane produced by the casting method is rough, stiff and partially soluble in water. However, the film made by the double decomposition method is smooth, flexible, and has low water solubility. The physicochemical characteristics of the prepared membranes were determined by Fourier transform infrared spectroscopy (FT-IR) and thermal gravimetric analysis (TGA/DTA). The morphology and components interface were observed by X-ray wide angle (WAXD), scanning electron microscopy (SEM) and electron microscopy (SEM/FEG). The spectral and crystallographic data showed the presence of an effective interaction between hydroxyapatite and CMC plasticized with lysine. Results also show that, the particles size of the composite decrease as the content of CMC increases, with an increase of a 2% by weight of CMC the size increases by 18±3nm. Produced membrane composite could be classified as tri-functional material: it could be useful for extracting toxic material bisphenol A (BPA) from baby food containers; has antimicrobial and antifungal properties; and a valuable candidate for use in bone tissue engineering.
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The main aim of this research work was to develop a new inorganic-organic film. Hydroxyapaptite (HAp) particles that represent the inorganic phase was mixed well with hydroxyethyl cellulose acetate (HECA), which representing the organic phase and then the inorganic-organic films were fabricated by evaporating of the solvent. The structure as well as the properties of the formed films were characterized using different analytical tools such as field emission scanning electron microscopy (FEG-SEM), thermo-gravimetric analysis (TGA), Fourier transform infra-red (FT-IR) spectroscopy. The obtained results revealed that, the HAp nanoparticles was well dispersed and well immobilized throughout the formed films. This can be attributed to the role of the nano- and micropores in the HECA substrate. In addition, a strong interaction occurred between HAp and HECA matrix. The results showed also good thermal stability and miscibility as well.
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Celulose/análogos & derivados , Durapatita/química , Celulose/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície , TemperaturaRESUMO
The molecular mechanism(s) by which steroids affect carcinogenesis is an active area of investigation. Recent studies with a series of related steroids in an in vitro DNA replication system produced a wide range of effects including enhancement and inhibition of DNA synthesis. The HeLa cell-free system used in these studies did not contain estrogen receptors. Since the majority of hormone effects on cellular replication have been attributed to interactions with estrogen receptors, an alternative description of the results was required. Quantitative structure-activity relationships (QSARs) were used to relate the observed bioactivity of these steroids with their structure. The results indicate that the percentage of DNA replication could be related to three parameters according to the following equation: %DNA = 23.9(+/-3.8)Xdipact + 57.8(+/-22.4)Hyd - 19.4(+/-10.4)Biophpi + 128.9, where Xdipact is the dipole moment on the X-axis, Hyd is the atomic hydrophobicity index, and Biophpi is the atomic pi population on the heteroatom found in the pharmacophore. For each molecule, the orientation of the functional groups changed the dipole moment value, and this descriptor was used as a selector of active conformations. A 3D-QSAR model was then constructed combining pharmacophoric features and global properties, and the active space and inactive space were defined using a Boolean volumetric operation.
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Replicação do DNA/efeitos dos fármacos , DNA/biossíntese , Receptores de Esteroides/metabolismo , Esteroides/farmacologia , Células HeLa , Humanos , Ligantes , Modelos Moleculares , Conformação Molecular , Receptores de Esteroides/química , Esteroides/química , Esteroides/metabolismo , Relação Estrutura-AtividadeRESUMO
A new method for the prediction and description of enantioselective separations on HPLC chiral stationary phases (CSPs) is described. Based on the combination of multivariate regression and neural networks, the method was successfully applied to the separation of a series of 29 aromatic acids and amides, chromatographed on three amylosic CSPs. Combinations of charge transfer, electrostatic, lipophilic, and dipole interactions, identified by multivariate regression, were found to describe retention and enantioselectivity, with highly predictive models being generated by the training of back-propagation neural networks.