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Recently, carbon neutrality has been promoted as a potentially practical solution to global CO2 emissions and increasing energy-consumption challenges. Many attempts have been made to remove CO2 from the environment to address climate change and rising sea levels owing to anthropogenic CO2 emissions. Herein, membrane technology is proposed as a suitable solution for carbon neutrality. This review aims to comprehensively evaluate the currently available scientific research on membranes for carbon capture, focusing on innovative microporous material membranes used for CO2 separation and considering their material, chemical, and physical characteristics and permeability factors. Membranes from such materials comprise metal-organic frameworks, zeolites, silica, porous organic frameworks, and microporous polymers. The critical obstacles related to membrane design, growth, and CO2 capture and usage processes are summarized to establish novel membranes and strategies and accelerate their scaleup.
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Water pollution by dyes and pesticides poses significant threats to our ecosystem. In this research, a visible-light ternary composite photocatalytic system was fabricated using graphene oxide (GO) by reducing with N2H4, modifying with KOH, and decorating with Ag/V2O5. The fabricated photocatalysts were characterized through FTIR, SEM, XRD, BET, PL, EDX, ESR, UV-vis spectroscopy, TGA, ESI-MS, and Raman spectroscopy. The point zero charge of the reduced and modified GO (RMGO/Ag/V2O5) was measured to be 6.7 by the pH drift method. This ternary composite was able to achieve complete removal of methyl orange (MO) and chlorpyrifos (CP) in solutions in 80 min under the optimum operation conditions (e.g., in terms of pollutant/catalyst concentrations, pH effects, and contact time). The role of active species responsible for photocatalytic activity was confirmed by scavenger analysis and ESR investigations. The potential mechanism for photocatalytic activity was studied through a fragmentation process carried out by MS analysis. Through nonlinear fitting of the experimental data, MO and CP exhibited the best fit results with the pseudo 1st-order kinetics (quantum yields of 1.07 × 10-3 and 2.16 × 10-3 molecules photon-1 and space-time yields of 1.53 × 10-5 and 2.7 × 10-5 molecules photon-1 mg-1, respectively). The structure of the nanomaterials remained mostly intact to support increased stability and reusability of the prepared photocatalysts even after 10 successive regeneration cycles.
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Compuestos Azo , Cloropirifos , Grafito , Plaguicidas , Colorantes/química , Ecosistema , LuzRESUMEN
A significant issue in developing metal-catalyzed plastic polymer materials is obtaining distinctive catalytic characteristics to compete with current plastics in industrial commodities. We performed first-principle DFT calculations on the key insertion steps for industrially important monomers, vinyl fluoride (VF) and 3,3,3-trifluoropropene (TFP), to explain how the ligand substitution patterns affect the complex's polymerization behaviors. Our results indicate that the favorable 2,1-insertion of TFP is caused by less deformation in the catalyst moiety of the complexes in contrast to the 1,2-insertion mode. In contrast to the VF monomer, the additional interaction between the fluorine atoms of 3,3,3-trifluoropropene and the carbons of the catalyst ligands also contributed to favor the 2,1-insertion. It was found that the regioselectivity of the monomer was predominated by the progressive alteration of the catalytic geometry caused by small dihedral angles that were developed after the ligand-monomer interaction. Based on the distribution of the 1,2- and 2,1-insertion products, the activity and selectivity were influenced by the steric environment surrounding the palladium center; thus, an increased steric bulk visibly improved the selectivity of the bulkier polar monomer (TFP) during the copolymerization mechanism. In contrast, better activity was maintained through a sterically less hindered Pd metal center; the calculated moderate energy barriers showed that a catalyst with less steric hindrance might provide an opportunity for a wide range of prospective industrial applications.
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The excessive amount of textile effluents disposed into the water streams is a common source of contamination of the hydrosphere. To efficiently remove pollutants in water bodies, there is growing demand for highly efficient, cost effective, and green remediation techniques. In line with such demand, a heterostructured photocatalyst (ZnO-ZnTe) has been prepared through the assembly of zinc oxide (ZnO) and zinc telluride (ZnTe). A synergistic interaction between surface adsorption and photocatalysis was explored for the removal of azo dye using a hierarchical superstructure under solar-light irradiation. Methylene blue (MB) was bleached by about 91% under visible irradiation for 2 h to support the role of the prepared heterostructures as effective photocatalysts (QY is 3.16 × 10-7 molecules/photon). Moreover, the kinetic reaction rate of ZnO-ZnTe superstructures was 19.0 µmol g-1 h-1, which was 1.54 and 1.97 times higher than those of pristine ZnO and ZnTe, respectively. These results may be ascribed to the presence of a common cation that may have helped in the diffusion of photogenerated electrons between ZnO and ZnTe, while efficiently suppressing the recombination frequency of photogenerated electrons and holes.
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Óxido de Zinc , Compuestos Azo , Catálisis , Azul de Metileno , Luz SolarRESUMEN
The generation of reactive oxygen species (ROS) during the photolysis of sunscreens and sun blockers poses consumer safety concerns while necessitating proper identification and quantitation of ROS species. Here, a colorimetric sensing approach has been developed based on a molecular probe (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2-H-tetrazolium-5-carboxanilide (XTT) tetrazolium salt) to quantitatively measure the photo-induced superoxide anion radicals (O2.) generated from the photocatalysis of zinc oxide nanoparticles (ZnO-NPs) in aqueous solutions. Note that superoxide anion radicals are assumed to be the main reactive oxygen species (ROS) generated from such photocatalysis. The characterisation of ZnO-NPs before and after irradiation showed average particle sizes of 616.5 and 295.3â¯nm and ζ-potential values of 0 and -24.4â¯mV, respectively. It is hoped that this proposed protocol can be further developed to efficiently detect other ROS present in inorganic sun blockers and to optimize the utility of various sunscreen formulations.
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Nanopartículas del Metal , Nanopartículas , Óxido de Zinc , Supervivencia Celular , Monitoreo del Ambiente , Nanopartículas del Metal/análisis , Sondas Moleculares , Especies Reactivas de Oxígeno , SuperóxidosRESUMEN
Industrialization and urbanization have produced a large amount of wastewater. Part of the municipal wastewater has been used as an irrigation source in urban/suburban areas. Its utilization, although economically beneficial, can significantly deteriorate the integrity of the ecological systems (e.g., in terms of quality of soil and resulting food products). The objectives of this study are to investigate the spatial distribution and bio-accumulation of heavy metals (e.g., Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn) in food crops (and topsoil) and associated health risks of their consumption in the area of Mangla Dam, Pakistan. To this end, studies were conducted to assess the risk factors such as the bioconcentration factor (BCF), health risk index (HRI), and daily intake of heavy metals (DIM). Accordingly, there was more contamination in Mangla Dam water irrigated zone (DWI) than in the groundwater irrigated zone (GWI). Co exhibited the maximum BCF of 7.45 for Eruca sativa and 6.61 for Brassica campestris in the GWI zone. Likewise, enhanced risk to human health was seen from of Cd, Cr, and Pb in Triticum aestivum and Eruca sativa grown in the DWI zone. It is recommended that the quality profile of wastewater discharge into freshwater ecosystems should be continuously monitored and regulated.
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Monitoreo del Ambiente , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Humanos , Pakistán , Medición de Riesgo , Aguas Residuales/químicaRESUMEN
Bisphenol A (BPA) is known to be an emerging pollutant in various environmental compartments. Human exposure to BPA occurs widely because it is commonly used as the raw material in a variety of industrial processes (e.g., the preparation of epoxy and polycarbonate resins). In this review, a brief survey was carried out to cover a range of photocatalytic materials (e.g., titania, zinc, silver, carbon, and bismuth) and their modified forms as an effective means to treat water systems contaminated with BPA. The overall efficiency and limitations of these catalysts are described for the photocatalytic treatment of BPA.
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Compuestos de Bencidrilo/química , Fenoles/química , Contaminantes Químicos del Agua/química , Catálisis , Humanos , Procesos Fotoquímicos , AguaRESUMEN
BACKGROUND AND AIMS: Many cases of difficult tracheal intubation remain unrecognized until after induction of anesthesia. McGrath and Airtraq videolaryngoscopes are among the novel laryngoscopes that have an advantage over the conventional laryngoscopes in case of unanticipated difficult airway. Thus, we did a comparative study between McGrath and Airtraq videolaryngoscopes to evaluate their efficacy in routine anesthesia practice. MATERIAL AND METHODS: Sixty anesthetized patients were divided into two groups using computer-based randomization, and tracheal intubation was performed using either McGrath or Airtraq laryngoscope. The primary outcome measures were duration and incidence of successful tracheal intubation. Hemodynamic response, glottic view (percentage of glottic opening score [POGO]), ease of intubation, and airway complications were also measured. RESULTS: Both McGrath and Airtraq groups were comparable in terms of incidence of successful tracheal intubation (93.3% vs. 96.6%), ease of intubation (70% vs. 77%), and POGO scoring. Intubation time was significantly shorter with Airtraq (13.5 vs. 17.8 s; P < 0.001). There were statistically significant changes in the heart rate and blood pressure after tracheal intubation in both the groups (P < 0.001); however, these parameters reached baseline within 5 min of intubation in both the groups. The incidence of injury was 10% with McGrath videolaryngoscope and 13.3% with Airtraq and was comparable. CONCLUSION: Both Airtraq and McGrath videolaryngoscope have high success rates of intubation. Airtraq is better than McGrath laryngoscope due to shorter tracheal intubation time.
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Determination of the availability of phases for specific separations is an important task achieved by a separation chemist. This becomes vital when the complex samples like biofluids are dealt with in proteome science. The work presented here involves the synthesis and application of terpolymeric sorbent with different functionalizations adopted for the selective enrichment of biomolecules of interest from biological fluids. Synthesis of terpolymer was carried out by the radical polymerization of monomers: methyl acrylate, acrylic acid and vinyl acetate with diethylene glycol dimethacrylate as cross-linking agent, benzoyl peroxide as initiator and chloroform as a porogenic solvent. Characterization was done through Fourier transform infrared spectroscopy, scanning electron microscopy and nitrogen adsorption porosimetry. The polymer was further modified to immobilized metal ion affinity chromatographic material, with immobilized Fe(3+)/La(3+) ions that allowed phosphopeptide enrichment from tryptic digests of standard proteins as well as milk, egg yolk and human serum. Sensitivity of enrichment down to 50 fmol was achieved in the presence of complex protein background as bovine serum albumin. Hydrophobicity was introduced through octadecyl amine, which provides comparable results to ZipTip C18/C4 for desalting of complex mixtures of all caseins. Analysis of the enriched content was performed by Matrix Assisted Laser Desorption Ionization Mass Spectrometry (MALDI-MS).
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Cromatografía de Afinidad/métodos , Fragmentos de Péptidos/análisis , Fosfoproteínas/análisis , Polímeros/química , Proteómica/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Animales , Yema de Huevo/química , Leche/química , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Tripsina/metabolismoRESUMEN
BACKGROUND AND AIMS: MacGrath videolaryngoscope is one of the recent videolaryngoscopes, which can be used to facilitate nasotracheal intubations using Scroeder directional stylet. MATERIAL AND METHODS: 15 patients, American Society of Anesthesiologists Grades I-II, undergoing tonsillectomy, requiring nasotracheal intubation were included. All patients were intubated with MacGrath videolaryngoscope and Schroeder stylet. Primary outcome measures were duration and ease of intubation. Overall success rate, number of attempts, modified Cormack-Lehane (C-L) grading, and complications were also recorded. RESULTS: All 15 intubations were successful during first laryngoscopy attempt. C-L Grade I views were obtained in 14 patients (93%) and Grade II view in one patient (7%). The time required to obtain the best C-L view was 9.4 ± 1.5 s. The time taken to complete tracheal intubation was 34.27 ± 3.38 s. Average numerical rating scale for tracheal intubation was 8.7 ± 0.9. Minor complications occurred in four patients (26.7%). CONCLUSIONS: MacGrath videolaryngoscope produces excellent laryngoscopic views in patients with normal airways. Impaction of tracheal tube on posterior nasopharyngeal wall can be overcome by Schroeder stylet.
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Melamine, a typical nitrogen enriched organic compound exhibiting great potential in the industrial sector, is exploited as an adulterant to inflate protein levels in dairy products, can pose serious threats to humans and therefore necessitates its swift detection and precise quantification at its first exposure. In this investigation, sensitive and reliable sensor probes were fabricated using CuO nanoparticles and its nanocomposites (NCs) with carbon nanotubes (CNTs), carbon black (CB), and graphene oxide (GO) to promptly quantify melamine in dairy products. The optical, morphological, and structural characteristics of the CuO-CNT NCs were achieved using diverse instrumental techniques including UV-visible spectroscopy, transmission electron microscopy, X- ray diffraction, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy and etc. The fabrication of glassy carbon electrodes (GCE) was accomplished by coating CuO-CNT NCs through a binder (5 % nafion). These sensor probes demonstrated outstanding electrochemical sensor performance with CuO-CNT NCs/Nafion/GCE sensor probe in terms of very low limit of detection (0.27 nM), good linearity range (0.05-0.5 nM), and relatively high sensitivity (93.924 µA µM-1 m-2) for melamine under optimized experimental conditions. Furthermore, the performance of CuO-CNT NCs/Nafion/GCE coated sensor probes was practically validated for the selective melamine detection in the real sample analysis of commercially available milk brands, which revealed significant figures of merit in a very short response time of 10 s. From the results, it was concluded that the current study might be helpful in the development of an efficient commercial sensor based on ultra-sensitive transition metal oxides in the field of health care monitoring, food stuffs in a broader scale as well as food applications.
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Polímeros de Fluorocarbono , Nanocompuestos , Nanotubos de Carbono , Triazinas , Humanos , Animales , Nanotubos de Carbono/química , Óxidos/química , Leche , Nanocompuestos/química , Técnicas Electroquímicas/métodos , ElectrodosRESUMEN
The benzothiophene based chromophores (A1D1-A1D5) with A-π-A configuration were designed via end-capped tailoring with benzothiophene type acceptors using reference compound (A1R). Quantum chemical calculations were accomplished at M06/6-311G(d,p) level to probe optoelectronic and photophysical properties of designed chromophores. Therefore, frontier molecular orbitals (FMOs), binding energy (Eb), open circuit voltage (Voc), transition density matrix (TDM), density of state (DOS) and UV-Vis analyses of A1R and A1D1-A1D5 were accomplished. The designed compounds (A1D1-A1D5) exhibited absorption values in the visible region as 616.316-649.676 nm and 639.753-665.508 nm in gas and chloroform phase, respectively, comparing with reference chromophore. An efficient charge transference from HOMO towards LUMO was found in A1D1-A1D5 chromophores which was further supported by TDM and DOS analyses. Among all chromophores, A1D2 exhibited unique characteristics such as reduced band gap (2.354 eV), higher softness (σ = 0.424 eV), lower exciton binding energy (0.491 eV) and maximum value of open circuit voltage (Voc = 1.981 V). Consequently, A1D2 may be considered as potential candidate for the development of optoelectronic devices. These analyses revealed that the studied compounds exhibited promising findings. They may be utilized in the realm of organic solar cells.
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Water pollution represents one of the most important problems affecting the health of living organisms, so it was necessary to work on the formation of active materials to get rid of pollutants. In this study, Titanium dioxide (TiO2) doping Zinc oxide (ZnO) nanocomposites were produced via simple sonication method at 500 Hz in ethanol medium. At different weight concentrations (2.5, 5, 7.5, and 10 %). The morphology, structure configuration, chemical bonding, crystalline phase, and surface properties of obtained nanocomposites were characterized via FESEM, BET, XRD, XPS, RAMAN and FTIR instrumentation. The nanocomposites were employed as an adsorbent to eliminate the methyl orange (MO) and Indigo Carmine (IC) dyes from an aqueous solution. Batch removal experiments revealed that the elimination of MO and IC dyes by the TiZnO surface was pH and doping Ti concentration-dependent, with maximum removal occurring at pH = 7 for MO and pH = 3 for IC contaminants at 10 % doping Ti concentration (Ti (10 %)@ZnO). Langmuir model fit the absorptive removal of MO and IC dyes into the Ti (10 %)@ZnO surface well. The maximal removal capacity of Ti (10 %)@ZnO nanocomposite was found to be 994.24 mg. g-1 for MO and 305.39 mg. g-1 for IC. The Ti (10 %)@ZnO nanocomposite showed remarkable high stability towards the removal of both dyes through consecutive four cycles.
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Performance evaluation of drilling fluids is essential for a successful drilling project, as they not only remove drill cuttings but also prevent undesired penetration or outflow of formation fluids by sealing off wellbore walls. However, concerns have been raised about the use of chemical additives in drilling fluids due to their toxicity and non-biodegradability. To this end, agricultural waste materials are recognized as a promising alternative as they are cost-effective, environmentally sustainable, and can be used as a substitute for lost circulation materials. Rice husk ash (RHA) has become popular as an additive due to its renewable characteristics, including its large surface area, silica content, and microporous structure. This research article explores the rheological properties of drilling fluid with RHA as a filter control medium. The results showed that increasing concentrations of RHA in the drilling mud significantly improved its rheology, particularly at higher concentrations (15 and 20 wt.%). The addition of RHA modified the filtration and rheological properties of the drilling mud, resulting in improved plastic viscosity, yield point, density, gel strength, and thixotropy. However, filter loss and mud cake thickness increased at elevated RHA concentrations. Furthermore, the pH test revealed that the mud's properties shifted toward the acidic region as the RHA concentration increased. The results indicate that RHA could be used as a sustainable and cost-effective alternative to conventional chemical additives with a positive environmental impact. This study may also provide valuable insights into the use of RHA in water-based bentonite mud and could serve as a guide for future research in the drilling industry.
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Oryza , Agricultura , Bentonita , Filtración , ReologíaRESUMEN
The conversion of biomass through thermochemical processes has emerged as a promising approach to meet the demand for alternative renewable fuels. However, these processes are complex, labor-intensive, and time-consuming. To optimize the performance and productivity of these processes, modeling strategies have been developed, with steady-state modeling being the most commonly used approach. However, for precision in biomass gasification, dynamic modeling and control are necessary. Despite efforts to improve modeling accuracy, deviations between experimental and modeling results remain significant due to the steady-state condition assumption. This paper emphasizes the importance of using Aspen Plus® to conduct dynamics and control studies of biomass gasification processes using different feedstocks. As Aspen Plus® is comprising of its Aspen Dynamics environment which provides a valuable tool that can capture the complex interactions between factors that influence gasification performance. It has been widely used in various sectors to simulate chemical processes. This review examines the steady-state and dynamic modeling and control investigations of the gasification process using Aspen Plus®. The software enables the development of dynamic and steady-state models for the gasification process and facilitates the optimization of process parameters by simulating various scenarios. Furthermore, this paper highlights the importance of different control strategies employed in biomass gasification, utilizing various models and software, including the limited review available on model predictive controller, a multivariable MIMO controller.
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Persistence and survival of Pseudomonas aeruginosa in chronic lung infections is closely linked to the biofilm lifestyle. One biofilm component, functional amyloid of P. aeruginosa (Fap), imparts structural adaptations for biofilms; however, the role of Fap in pathogenesis is still unclear. Conservation of the fap operon encoding Fap and P. aeruginosa being an opportunistic pathogen of lung infections prompted us to explore its role in lung infection. We found that Fap is essential for establishment of lung infection in rats, as its genetic exclusion led to mild focal infection with quick resolution. Moreover, without an underlying cystic fibrosis (CF) genetic disorder, overexpression of Fap reproduced the CF pathotype. The molecular basis of Fap-mediated pulmonary adaptation was explored through surface-associated proteomics in vitro. Differential proteomics positively associated Fap expression with activation of known proteins related to pulmonary pathoadaptation, attachment, and biofilm fitness. The aggregative bacterial phenotype in the pulmonary niche correlated with Fap-influenced activation of biofilm sustainability regulators and stress response regulators that favored persistence-mediated establishment of pulmonary infection. Fap overexpression upregulated proteins that are abundant in the proteome of P. aeruginosa in colonizing CF lungs. Planktonic lifestyle, defects in anaerobic pathway, and neutrophilic evasion were key factors in the absence of Fap that impaired establishment of infection. We concluded that Fap is essential for cellular equilibration to establish pulmonary infection. Amyloid-induced bacterial aggregation subverted the immune response, leading to chronic infection by collaterally damaging tissue and reinforcing bacterial persistence. IMPORTANCE Pseudomonas aeruginosa is inextricably linked with chronic lung infections. In this study, the well-conserved Fap operon was found to be essential for pathoadaptation in pulmonary infection in a rat lung model. Moreover, the presence of Fap increased pathogenesis and biofilm sustainability by modulating bacterial physiology. Hence, a pathoadaptive role of Fap in pulmonary infections can be exploited for clinical application by targeting amyloids. Furthermore, genetic conservation and extracellular exposure of Fap make it a commendable target for such interventions.
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Fibrosis Quística , Infecciones por Pseudomonas , Ratas , Animales , Pseudomonas aeruginosa/metabolismo , Proteoma/metabolismo , Infecciones por Pseudomonas/microbiología , Biopelículas , Pulmón/microbiología , Fibrosis Quística/microbiologíaRESUMEN
The excessive use of antibiotics and their ultimate routes to the environment have prompted the drug resistance, which is becoming a major ecological issue. In this work, we have evaluated the performance of quaternary ammonium poly (2, 6-dimethyl-1,4-phenylene oxide) and polyvinyl alcohol (QPPO/PVA) based anion exchange membrane against cefixime (a third generation cephalosporin antibiotic) present in hospital effluents. The membrane's surface morphology was studied through scanning electron microscopy. The optimization of experimental parameters through Response Surface Methodology helped to evaluate the inter parameter dependence and predict maximum uptake capacity (qe). The speculated value of qe (6.72 mg g-1) obtained through central composite design was close to the experimental value of 7.01 mg g-1 with percent relative error of 4.31%. Further, the evaluation of experimental data using isotherms (Langmuir and Freundlich) and kinetic models (pseudo-first-order and second-order) proposed that the interactions between cefixime and the membrane were physisorptive in nature. The intra-day and inter-day assays exhibited lower %RSD values of 0.4% (n = 5) and 0.3% (n = 5). Furthermore, a percentage recovery of 98.2% (n = 9) and limit of detection 1 × 10-5 µg mL-1 was observed. The chromatogram of the treated water samples presented only negligible amount of cefixime indicating a great potential of QPPO/PVA membrane for the removal of cefixime from real water samples. The membrane could be regenerated for three consecutive cycles without any prominent loss in efficiency.
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Antibacterianos , Proyectos de Investigación , Cefixima , Cinética , Aniones , Agua , AdsorciónRESUMEN
The utilization of dye adsorption through metal-organic frameworks represents an eco-friendly and highly effective approach in real water treatment. Here, ultrasound assisted adsorption approach was employed for the remediation of three dyes including methylene blue (MB), malachite green (MG), and congo red (CR) from real water samples using zirconium(IV)-based adsorbent (UiO-66-NH2). The adsorbent was characterized for structural, elemental, thermal and morphological features through XRD, XPS, FTIR, thermogravimetric analysis, SEM, BET , and Raman spectroscopy. The adsorption capacity of adsorbent to uptake the pollutants in aqueous solutions was investigated under different experimental conditions such as amount of UiO-66-NH2 at various contact durations, temperatures, pH levels, and initial dye loading amounts. The maximum removal of dyes under optimal conditions was found to be 938, 587, and 623 mg g-1 towardMB, MG, and CR, respectively. The adsorption of the studied dyes on the adsorbent surface was found to be a monolayer and endothermic process. The probable mechanism for the adsorption was chemisorption and follows pseudo-second-order kinetics. From the findings of regeneration studies, it was deduced that the adsorbent can be effectively used for three consecutive cycles without any momentous loss in its adsorption efficacy. Furthermore, UiO-66-NH2 with ultrasound-assisted adsorption might help to safeguard the environment and to develop new strategies for sustainability of natural resources.
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The present study aimed to fabricate a novel polymeric spongy composite to enhance skin regeneration composed of Nystatin (antifungal agent) and Silver Nanoparticles (AgNps). Different formulations (F1-F8) were developed & characterized by using various analytical techniques. AgNps synthesized by chemical reduction method showed spherical morphology 2 µm in size showed by SEM and XRD. A fine porous structure of gel embedded with AgNps having an amorphous structure with 10 % crystallinity due to AgNps was found. IR spectra revealed no chemical interaction between polymers and Nystatin. An increase in thermal stability of formulation was observed till 700 â analyzed by Differential Scanning Calorimetry. Cytotoxic analysis on L929 mouse skin fibroblast cells showed a decrease in cell viability as Ag concentration increased (inactivating Fibroblast and keratinocytes) while 10 mg composition was found safest concentration (94%). Optimized formulation (F2) presented in-vitro drug release up to 90.59% ± 0.76 at pH 7.4, swelling studies (87.5% ± 0.57), water retention (26.60 ± 0.34), pH (5.31 ± 0.03). In the animal burn model, the group that received CHG/Ag/Nystatin healed the wound significantly (p < 0.05). These results suggested that optimized carrier can be used for other anti-fungal drugs facilitating the early healing of the wound.
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Ácido Hialurónico , Nanopartículas del Metal , Animales , Ratones , Nistatina , Plata , Cicatrización de Heridas , Sistemas de Liberación de MedicamentosRESUMEN
Aspergillus parasiticus (A. parasiticus) is known for producing aflatoxins and is a major threat to the food industry. Green synthesis of nanoparticles (NPs) is a cost-effective and environment-friendly approach. A variety of NPs have been explored as antifungal agents; however, their antifungal characteristics need to be further enhanced to compete with traditional fungicides. The present work describes the green synthesis of ZnO and CuO NPs by precipitation method using aqueous leaf extract of Manilkara zapota and their surface modification through polyaniline (PANI). Still, there is no published study on the application of PANI-coated particles as antifungal agents against A. parasiticus and hence was the focus of this work. The polymer-coated NPs were synthesized, characterized, and investigated for their antifungal properties against A. parasiticus. Textural and structural characterization of PANI-coated and non-coated ZnO and CuO NPs were confirmed through FT-IR, SEM, and XRD techniques. The PANI-coated NPs presented higher fungal growth inhibition (%) as compared to the non-coated ones. The maximum inhibition of 77 ± 2% (n = 3) was shown by PANI/ZnO NPs at a concentration of 12 mmol L-1 and 72 h of incubation. The non-coated NPs presented a lower inhibition rate with respect to their coated NPs, thus justifying the role of polymeric coating in improving antifungal efficiency.