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1.
Artículo en Inglés | MEDLINE | ID: mdl-39240432

RESUMEN

The extensive use of pharmaceuticals has increased their presence in the environment, posing significant ecological and public health concerns. The current study reports the magnetic nanocomposite (M-ABAC) synthesis using the algal-bacterial sludge as the precursor for activated carbon and evaluates its potential in fluoroquinolone antibiotics removal. The activated carbon from algal-bacterial sludge was composited with Fe3O4 nanoparticles using the co-precipitation method. The M-ABAC was characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), Brunauer-Emmett-Teller (BET) analysis, and vibrating sample magnetometry (VSM). M-ABAC was employed for antibiotic ciprofloxacin (CIP) removal by combined adsorption and heterogenous Fenton degradation. The adsorption studies reveal that the Langmuir isotherm best fits the experimental data, with a maximum adsorption capacity of 81.6 mg/g. Pseudo-second-order kinetic model well describes adsorption kinetics. Fenton catalytic degradation was performed using H2O2 as the activating agent. The optimal H2O2 dosage was observed to be 10 mM. A CIP adsorptive removal efficiency of 75% was observed at 2 g/L dosage of M-ABAC in a 200 ppm CIP solution. Simultaneous adsorption and Fenton catalytic degradation further enhanced the removal efficiency to 92%. Radical scavengers experiment revealed that the hydroxyl radical (•OH) was the dominant reactive oxidation species. The degradation products of the CIP were identified using liquid chromatography quadrupole time-of-flight mass spectroscopy (LC-QTOF-MS). The possible CIP degradation mechanisms include decarboxylation, piperazine moiety degradation, defluorination, and hydroxylation.

2.
Sci Rep ; 14(1): 17976, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39095409

RESUMEN

In awareness of industrial dye wastewater, carbon quantum dots (CQDs) and cobalt zinc ferrite (CZF) nanocomposites were synthesised for the making of carbon quantum dots coated cobalt zinc ferrite (CZF@CQDs) nanophotocatalyst using oxidative polymerization reaction. The results of TEM, zeta potential value, and FTIR confirm highly dispersed 1-4 nm particles with the - 45.7 mV carboxylic functionalized surface of CQDs. The results of the synthesised CZF@CQDs photocatalyst showed an average particle size of ~ 15 nm according to TEM, SEM, and XRD. The photocatalyst showed a 1.20 eV band gap, which followed the perfect visible light irradiation. TGA and DTA revealed the good thermal stability of the nanophotocatalyst. VSM was carried out, and the saturation magnetisations for CZF and CZF@CQDs were 42.44 and 36.14 emu/g, respectively. A multipoint study determined the BET-specific surface area of the CZF@CQDs photocatalyst to be 149.87 m2/g. Under visible light irradiation, the final CZF@CQDs nanophotocatalyst demonstrated remarkable efficiency (~ 95% within 25 min) in the photocatalytic destruction of Reactive Blue 222 (RB 222) and Reactive Yellow 145 (RY 145) dyes, as well as mechanical stability and recyclability. Even after the recycling of the degradation study, the nanophotocatalyst efficiency (~ 82%, 7th cycles) was predominantly maintained. The effects of several parameters were also investigated, including initial dye concentration, nanophotocatalyst concentration, CQD content, initial pH of the dye solution, and reaction kinetics. Degradation study data follow the first-order reaction rate (R2 > 0.93). Finally, a simple and low-cost synthesis approach, rapid degradation, and outstanding stability of the CQD-coated CZF nanophotocatalyst should make it a potential photocatalyst for dye wastewater treatment.

3.
J Colloid Interface Sci ; 675: 670-682, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38996697

RESUMEN

Lignin hydrogels have garnered significant attention due to their distinctive three-dimensional structures and potent swelling ability. In this work, a novel magnetic nanocomposite lignin hydrogel (MNLH) was fabricated through organic synthesis and solution immersion reduction. The obtained MNLH was used to activate persulfate(PDS) for pesticide degradation. Scanning electron microscopy (SEM), X-ray diffractometry (XRD), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR) were used to characterize the structure and morphology of MNLH. The influence of factors such as the lignin hydrogel to nano-zero-valent iron (nZVI) and copper oxide (CuO) mass ratio, MNLH dosage, initial pH on the MNLH/PDS/imidacloprid (IMI) system. Remarkably, the MNLH/PDS/IMI system has a removal rate of up to 100%. Quenching and electron paramagnetic resonance (EPR) studies disclosed that the MNLH/PDS system degraded IMI through a combination of free radical and non-free radical pathways, with the latter being dominant. More importantly, in this study, the toxicity and hydrolysis sites of IMI were analyzed using ECOSAR and Gaussian09, respectively, confirming the feasibility of activating persulfate with MNLH. These findings underscore the potential of MNLH as a function material suitable for facilitating the persulfate-activated degradation of organic pollutants.

4.
Chemosphere ; 361: 142548, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38852637

RESUMEN

This study evaluated the effectiveness of using nanocomposite (NCs) of xanthan gum grafted polyacrylamide crosslinked Borax - iron oxide nanoparticle (XG-g-pAAm-CL-Borax-IONP) to remove the amoxicillin antibiotic (AMX) from an aquatic environment. To confirm the structural characteristics of the prepared XG-g-pAAm-CL-Borax-IONP NCs, unique characterization methods (XRD, FT-IR, FE-SEM, EDX, BET, TGA, Zeta, and VSM) were used. Adsorption experimental setups were performed with the influence of solution pH (4-9), the effect of adsorbent dose (0.003-0.02 g), the effect of contact time (5-45 min), and the effect of initial AMX concentration (50-400 mg/L) to achieve the most efficient adsorption conditions. Based on the Freundlich isotherm model, XG-g-pAAm-CL-Borax-IONP NCs provided the maximum AMX adsorption capacity of 1183.639 mg/g. This research on adsorption kinetics also established that the pseudo-second-order model (R2 = 0.991) is outstanding compatibility with the experimental results. AMX adsorption on the NCs may occur through intermolecular hydrogen bonding, diffusion, and trapping into the polymer network. Even after five cycles, these NCs still displayed the best performance. Based on these results, XG-g-pAAm-CL-Borax-IONP NCs may be a viable material for the purification of AMX from contaminated water.


Asunto(s)
Resinas Acrílicas , Amoxicilina , Boratos , Nanocompuestos , Polisacáridos Bacterianos , Contaminantes Químicos del Agua , Nanocompuestos/química , Contaminantes Químicos del Agua/química , Resinas Acrílicas/química , Amoxicilina/química , Polisacáridos Bacterianos/química , Adsorción , Boratos/química , Cinética , Antibacterianos/química , Purificación del Agua/métodos , Concentración de Iones de Hidrógeno
5.
Int J Biol Macromol ; 271(Pt 2): 132547, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38782322

RESUMEN

Nanocatalysts play a vital role in chemical reactions, energy conservation, and pollution control. They significantly contribute to organic synthesis by using natural polymers as nanoparticle substrates in nanocatalysts. Natural hydrogels made from polysaccharide and/or protein sources may be used to accomplish this. Recent research has focused on using layered double-hydroxides (LDHs) in composites having catalytic properties. Magnetic features of the catalyst allow its extraction from the environment using a magnet after the reaction, improving product efficiency. This work developed a catalyst for producing physiologically relevant polyhydroquinoline derivatives using a novel magnetic nanocomposite containing natural cellulose-gellan gum hydrogel and MgAl LDH. The Cell-GG hydrogel/MgAl LDH/Fe3O4 nanocomposite showed over 90 % efficiency in one-pot production of polyhydroquinoline derivatives by asymmetric Hantzsch condensation. Dimedone, ammonium acetate, ethyl acetoacetate, and different substituted aldehydes were employed in successive processes to create polyhydroquinoline derivatives. High product efficiency, quick reaction time, room temperature functioning, and easy separation with a magnet suggest a potent catalyst. Interestingly, the catalyst retains 80 % of its original capability after four cycles. Additionally, the Cell-GG hydrogel/MgAl LDH/Fe3O4 nanocomposite was analyzed using several methods, including FT-IR, FE-SEM, EDX, XRD, VSM and TGA, to obtain insight into its chemical and physical characteristics.


Asunto(s)
Celulosa , Hidrogeles , Polisacáridos Bacterianos , Quinolinas , Polisacáridos Bacterianos/química , Celulosa/química , Catálisis , Quinolinas/química , Hidrogeles/química , Hidrogeles/síntesis química , Nanocompuestos/química
6.
Anal Chim Acta ; 1307: 342622, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719403

RESUMEN

BACKGROUND: Trace levels of organic and inorganic lead and mercury species in the environment, including divalent lead (Pb2+), trimethyllead (TML), divalent mercury (Hg2+), monomethylmercury (MeHg), and ethylmercury (EtHg), are highly toxic to humans and ecology. It is of great importance for speciation of lead and mercury to evaluate the toxicity of lead and mercury and their biogeochemistry in the environment. However, simultaneous multi-elemental enrichment and speciation at trace level remains a challenge. There are few reports of simultaneous magnetic solid-phase extraction (MSPE) of organic and inorganic lead and mercury species at trace level in the real water. RESULTS: In this work, a novel core-shell magnetic hydrazine-linked covalent organic frameworks (Fe3O4@COF-TCH) was prepared for the first time by grafting hydrazine-linked COFs on the Fe3O4 nanoparticles. Fe3O4@COF-TCH with abundant thione and imino groups has strong adsorption for lead and mercury species. Based on it, a simple and practical magnetic solid-phase extraction high-performance liquid chromatography-inductively coupled plasma mass spectrometry (MSPE-HPLC-ICP-MS) method was developed for extraction and determination of trace lead and mercury species, including Hg2+, MeHg, EtHg, Pb2+ and TML. The limits of detection (3δ) of the developed method were 0.08, 0.81, 0.90, 0.56 and 0.88 ng L-1 with the enrichment factors (EFs) of 384, 376, 379, 389 and 360-fold for Pb2+, TML, Hg2+, MeHg and EtHg, respectively. The high accuracy and reproducibility have been proved by the spiked recoveries (94.4-103 %) in real samples. SIGNIFICANCE: The proposed method with simple operation and high sensitivity has been successfully applied to simultaneous speciation of lead and mercury at trace levels in the water samples with complicated matrices, including underground water, surface water, sea water. Meanwhile, it has the advantages of cost-saving, labor-saving and time-saving and is suitable for the investigation and risk assessment in water. The development of MSPE-HPLC-ICP-MS method provides ideas and guidance for the simultaneous multi-elemental enrichment and speciation.

7.
Heliyon ; 10(5): e27235, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38449605

RESUMEN

Monitoring phosphorus fertilization is crucial for controlling the concentration of biologically available soil P. Over the years, several methodologies have been used, including successive cropping in a greenhouse or field, as well as extractions employing P sink procedures. The latter procedures are ideal laboratory experiments to show the soil's ability to supply P and to explore the P-residual release kinetics. Following these methodologies, long-term P desorption studies have been developed using dialysis membrane tubes filled with nanomaterial solutions. In this study, a magnetic nanocomposite (Fe3O4/Al2O3/MnO2) was synthesized and characterized utilizing cutting-edge instruments such as XRD, FTIR, FAAS, BET, SEM, and EDX. The resulting material had a crystalline size and surface area of 22.75 nm and 203.69 m2/g, respectively, and was employed for long-term P-desorption and kinetics experiments while filled in dialysis membrane tubes. The P-desorption experiment was conducted on four separate acidic soil samples that were cultured for 122 days with four different P concentrations. The findings demonstrated a direct relationship between P-desorbed and P-treatment, as well as with desorption time. The minimum desorption was obtained from the control of Boji Dirmaji soil P0 (1.16-9.36) and the highest desorption from Nedjo soil with P3 (5.23-30.35 mg/kg) treatment over 1-28 days. The rate of P release from soil to solution or diffusion through the membrane was determined by pseudo-first-order kinetics with a rate constant (0.021-0.028 hr-1). This method has the potential to measure fixed-P availability by mimicking it as a plant would, with high P-desorption efficiency and quick P-release capacity.

8.
Molecules ; 29(6)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38542830

RESUMEN

The Fe3O4@SiO2@ZnO composite was synthesized via the simultaneous deposition of SiO2 and ZnO onto pre-prepared Fe3O4 nanoparticles. Physicochemical methods (TEM, EDXS, XRD, SEM, FTIR, PL, zeta potential measurements, and low-temperature nitrogen adsorption/desorption) revealed that the simultaneous deposition onto magnetite surfaces, up to 18 nm in size, results in the formation of an amorphous shell composed of a mixture of zinc and silicon oxides. This composite underwent modification to form Fe3O4@SiO2@ZnO*, achieved by activation with H2O2. The modified composite retained its structural integrity, but its surface groups underwent significant changes, exhibiting pronounced catalytic activity in the photodegradation of methyl orange under UV irradiation. It was capable of degrading 96% of this azo dye in 240 min, compared to the initial Fe3O4@SiO2@ZnO composite, which could remove only 11% under identical conditions. Fe3O4@SiO2@ZnO* demonstrated robust stability after three cycles of use in dye photodegradation. Furthermore, Fe3O4@SiO2@ZnO* exhibited decreased PL intensity, indicating an enhanced efficiency in electron-hole pair separation and a reduced recombination rate in the modified composite. The activation process diminishes the electron-hole (e-)/(h+) recombination and generates the potent oxidizing species, hydroxyl radicals (OH˙), on the photocatalyst surface, thereby playing a crucial role in the enhanced photodegradation efficiency of methyl orange with Fe3O4@SiO2@ZnO*.

9.
Biomed Mater ; 19(3)2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38537375

RESUMEN

The development of new three-dimensional biomaterials with advanced versatile properties is critical to the success of tissue engineering (TE) applications. Here, (a) bioactive decellularized tendon extracellular matrix (dECM) with a sol-gel transition feature at physiological temperature, (b) halloysite nanotubes (HNT) with known mechanical properties and bioactivity, and (c) magnetic nanoparticles (MNP) with superparamagnetic and osteogenic properties were combined to develop a new scaffold that could be used in prospective bone TE applications. Deposition of MNPs on HNTs resulted in magnetic nanostructures without agglomeration of MNPs. A completely cell-free, collagen- and glycosaminoglycan- rich dECM was obtained and characterized. dECM-based scaffolds incorporated with 1%, 2% and 4% MNP-HNT were analysed for their physical, chemical, andin vitrobiological properties. Fourier-transform infrared spectroscopy, x-ray powder diffractometry and vibrating sample magnetometry analyses confirmed the presence of dECM, HNT and MNP in all scaffold types. The capacity to form apatite layer upon incubation in simulated body fluid revealed that dECM-MNP-HNT is a bioactive material. Combining dECM with MNP-HNT improved the thermal stability and compressive strength of the macroporous scaffolds upto 2% MNP-HNT.In vitrocytotoxicity and hemolysis experiments showed that the scaffolds were essentially biocompatible. Human bone marrow mesenchymal stem cells adhered and proliferated well on the macroporous constructs containing 1% and 2% MNP-HNT; and remained metabolically active for at least 21 din vitro. Collectively, the findings support the idea that magnetic nanocomposite dECM scaffolds containing MNP-HNT could be a potential template for TE applications.


Asunto(s)
Nanotubos , Andamios del Tejido , Humanos , Arcilla/química , Andamios del Tejido/química , Estudios Prospectivos , Ingeniería de Tejidos/métodos , Fenómenos Magnéticos , Nanotubos/química , Matriz Extracelular/química
10.
Chemosphere ; 356: 141770, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38554866

RESUMEN

The objective of the present study was to employ a green synthesis method to produce a sustainable ZnFe12O19/BiOI nanocomposite and evaluate its efficacy in the photocatalytic degradation of metronidazole (MNZ) from aqueous media. An artificial neural network (ANN) model was developed to predict the performance of the photocatalytic degradation process using experimental data. More importantly, sensitivity analysis was conducted to explore the relationship between MNZ degradation and various experimental parameters. The elimination of MNZ was assessed under different operational parameters, including pH, contaminant concentration, nanocomposite dosage, and retention time. The outcomes exhibited high a desirability performance of the ANN model with a coefficient correlation (R2) of 0.99. Under optimized circumstances, the MNZ elimination efficiency, as well as the reduction in chemical oxygen demand (COD) and total organic carbon (TOC), reached 92.71%, 70.23%, and 55.08%, respectively. The catalyst showed the ability to be regenerated 8 times with only a slight decrease in its photocatalytic activity. Furthermore, the experimental data obtained demonstrated a good agreement with the predictions of the ANN model. As a result, this study fabricated the ZnFe12O19/BiOI nanocomposite, which gave potential implication value in the effective decontamination of pharmaceutical compounds.


Asunto(s)
Bismuto , Metronidazol , Nanocompuestos , Redes Neurales de la Computación , Contaminantes Químicos del Agua , Zinc , Nanocompuestos/química , Bismuto/química , Catálisis , Metronidazol/química , Contaminantes Químicos del Agua/química , Zinc/química , Fotólisis , Compuestos Férricos/química
11.
ACS Biomater Sci Eng ; 10(4): 2143-2150, 2024 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-38442336

RESUMEN

Highly selective extraction of phosphopeptides is necessary before mass spectrometry (MS) analysis. Herein, zirconium phthalocyanine-modified magnetic nanoparticles were prepared through a simple method. The Fe-O groups on Fe3O4 and the zirconium ions on phthalocyanine had a strong affinity for phosphopeptides based on immobilized metal ion affinity chromatography (IMAC). The enrichment platform exhibited low detection limit (0.01 fmol), high selectivity (α-/ß-casein/bovine serum albumin, 1/1/5000), good reusability (10 circles), and recovery (91.1 ± 1.1%) toward phosphopeptides. Nonfat milk, human serum, saliva, and A549 cell lysate were employed as actual samples to assess the applicability of the enrichment protocol. Metallo-phthalocyanine will be a competitive compound for designing highly efficient adsorbents and offers a new approach to phosphopeptide analysis.


Asunto(s)
Isoindoles , Nanopartículas de Magnetita , Fosfopéptidos , Humanos , Fosfopéptidos/análisis , Fosfopéptidos/química , Circonio/química , Adsorción
12.
Environ Res ; 249: 118415, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38316383

RESUMEN

Providing safe access to water and addressing the impact of waterborne diseases, which claim over two million lives annually, is a major contribution to water purification. The study introduces a novel nanocomposite, Ch/Fe3O4/α-MoO3, which exhibits outstanding photocatalytic efficacy under visible light. An in-depth investigation of the nanocomposite's synthesis, characterization, and photodegradation mechanisms reveals its outstanding capabilities. Photocatalytic activity is influenced by the catalytic dose, pH, dye concentration, and reaction time, according to the study. A response surface method is used to determine the optimal conditions for Rhodamine B degradation, which results in 96.3% removal efficiency at pH 8.5, dye concentration 25 mg/L, nanocomposite dose at 22 mg/L, and reaction time 50 min. As a result of its high surface area, biocompatibility, availability, and magnetization with iron compounds, Chitosan is an excellent substrate for enhancing the photocatalytic properties of MoO3 nanoparticles. A nanocomposite with an energy band of 3.18 eV exhibits improved visible light absorption. This study confirms the nanocomposite's recyclability and stability, affirming its practicality. Besides dye removal, it offers hope for the global quest for clean water sources by addressing a broader range of waterborne contaminants. By combining molybdenum and magnetite, nanocomposite materials facilitate the degradation of pollutant and bacteria, contributing positively to society's quest for clean and safe water. It emphasizes the role nanotechnology plays in preserving human health and well-being in combating waterborne diseases.


Asunto(s)
Luz , Nanocompuestos , Rodaminas , Aguas Residuales , Contaminantes Químicos del Agua , Rodaminas/química , Nanocompuestos/química , Contaminantes Químicos del Agua/química , Aguas Residuales/química , Catálisis , Purificación del Agua/métodos , Fotólisis , Colorantes/química , Molibdeno/química
13.
Int J Biol Macromol ; 259(Pt 2): 129263, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38191117

RESUMEN

In the present study, starch/zeolitic imidazole framework-67 (ZIF-67) modified magnetic montmorillonite nanocomposite adsorbent to remove tetracycline (TC) as an emerging antibiotic-based contaminant from aqueous media. The surface properties of the adsorbents were investigated using FTIR, XRD, SEM, EDX-Map, XPS, TEM, BET, and VSM analysis. The specific surface area of MMT, St/MMT-MnFe2O4, and St/MMT-MnFe2O4-ZIF-67 magnetic nanocomposite samples were found to be 15.63, 20.54, and 588.41 m2/g, respectively. The influence of pH, adsorbent amount, initial TC concentration, temperature, contact time, and coexisting ions on TC elimination was explored in a batch adsorption system. The kinetic and equilibrium data were well matched with the pseudo-second-order and Langmuir isotherm models, respectively. The maximum monolayer adsorption capacities of TC were obtained to be 40.24, 66.1, and 135.2 mg/g by MMT, St/MMT-MnFe2O4, and St/MMT-MnFe2O4-ZIF-67 magnetic nanocomposite adsorbents, respectively. Also, thermodynamic studies illustrated that the TC adsorption process is exothermic and spontaneous. Furthermore, the magnetic nanocomposite adsorbent St/MMT-MnFe2O4-ZIF-67 showed good reusability and could be recycled for up to five cycles. This excellent adsorption performance, coupled with the facile separation of the magnetic nanocomposite, gave St/MMT-MnFe2O4-ZIF-67 a high potential for TC removal from aqueous media.


Asunto(s)
Nanocompuestos , Contaminantes Químicos del Agua , Zeolitas , Bentonita , Zeolitas/química , Descontaminación , Tetraciclina , Antibacterianos , Agua/química , Adsorción , Nanocompuestos/química , Fenómenos Magnéticos , Imidazoles , Contaminantes Químicos del Agua/química , Cinética , Concentración de Iones de Hidrógeno
14.
Environ Res ; 247: 118193, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38220086

RESUMEN

In the presented study, a novel polypyrrole-decorated bentonite magnetic nanocomposite (MBnPPy) was synthesized for efficient removal of both anionic methyl orange (MO) and cationic crystal violet (CV) dyes from contaminated water. The synthesis of this novel adsorbent involved a two-step process: the magnetization of bentonite followed by its modification through in-situ chemical polymerization. The adsorbent was characterized by SEM/EDX, TEM/SAED, BET, TGA/DTA-DTG, FTIR, VSM, and XRD studies. The investigation of the adsorption properties of MBnPPy was focused on optimizing various parameters, such as dye concentration, medium pH, dosage, contact time, and temperature. The optimal conditions were established as follows: dye concentration of Co (CV/MO) at 100 mg/L, MBnPPy dosage at 2.0 g/L, equilibrium time set at 105 min for MO and 120 min for CV, medium pH adjusted to 5.0 for MO dye and 8.0 for CV dye, and a constant temperature of 303.15 K. The different kinetic and isotherm models were applied to fit the experimental results, and it was observed that the Pseudo-2nd-order kinetics and Langmuir adsorption isotherm were the best-fitted models. The maximal monolayer adsorption capacities of the adsorbent were found to be 78.74 mg/g and 98.04 mg/g (at 303.15 K) for CV and MO, respectively. The adsorption process for both dyes was exothermic and spontaneous. Furthermore, a reasonably good regeneration ability of MBnPPy (>83.45%/82.65% for CV/MO) was noted for up to 5 adsorption-desorption cycles with little degradation. The advantages of facile synthesis, cost-effectiveness, non-toxicity, strong adsorption capabilities for both anionic and cationic dyes, and easy separability with an external magnetic field make MBnPPy novel.


Asunto(s)
Compuestos Azo , Nanocompuestos , Contaminantes Químicos del Agua , Colorantes/química , Adsorción , Polímeros , Violeta de Genciana/química , Bentonita/química , Pirroles , Agua/química , Fenómenos Magnéticos , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno , Cinética
15.
Environ Sci Pollut Res Int ; 31(9): 13246-13269, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38244163

RESUMEN

The upgrade of sustainable resource waste into a valuable and beneficial material is an urgent task. The current paper outlines the development of an economical, sustainable, and prolonged adsorbent derived from Sargassum siliquastrum biomass and its use for potent 2,4-dichlorophenoxyacetic acid (2,4-D) removal. A simple carbonization approach was applied to obtain the highly functionalized carbon structure, which was subsequently transformed into a novel magnetic nanoadsorbent. The magnetic nanoadsorbent was characterized using Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), Brunauer Emmett Teller (BET)-specific surface area, and vibrating sample magnetometer (VSM). The characterization results confirm the successful formation of a high specific surface area and a uniform distribution of Fe3O4/NiS NPs grafted activated carbon. The adsorption kinetics was more accurately described via the pseudo-second order model; nevertheless, the isothermal data showed that the Langmuir model was most suitable. The monolayer adsorption capacity for 2,4-D was 208.26 ± 15.75 mg/g at 328 K. The favourability and spontaneity of the adsorption process were demonstrated by thermodynamic studies. The adsorbent displayed exceptional selectivity for 2,4-D and high stability in multi-cycle use. Electrostatic attraction, π-π stacking, and hydrogen bonding were all believed to have an impact on the sorbent's robust 2,4-D adsorption. Analyses of real tap and Nile River water samples showed little effect of the sample matrix on 2,4-D adsorption. This study presents an innovative approach for developing highly efficient adsorbent from natural biomass and offers an affordable way to recycle algal waste into beneficial materials.


Asunto(s)
Herbicidas , Nanotubos , Sargassum , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico/química , Fenómenos Magnéticos , Ácido 2,4-Diclorofenoxiacético , Cinética , Contaminantes Químicos del Agua/química , Espectroscopía Infrarroja por Transformada de Fourier , Concentración de Iones de Hidrógeno
16.
Int J Biol Macromol ; 258(Pt 2): 129039, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38154704

RESUMEN

Compared with traditional tedious organic solvent-assisted separation process in natural medicinal chemistry, cytomembrane (CM) fishing technique became a more appealing and greener choice for screening bioactive components from natural products. However, its large-scale practical value was greatly weakened by the easy fall-off of CMs from magnetic supports, rooted in the instability of common Fe3O4 particles and their insufficient interaction with CMs. In this research, a new green biostable platform was developed for drug screening through the integration of hyperbranched quaternized hydrothermal magnetic carbon spheres (HQ-HMCSs) and CMs. The positive-charged HQ-HMCSs were constructed by chitosan-based hydrothermal carbonization onto Fe3O4 nanospheres and subsequent aqueous hyperbranching quaternization with 1,4-butanediol diglycidyl ether and methylamine. The strong interaction between HQ-HMCSs and CMs was formed via electrostatic attraction of HQ-HMCSs to negative-charged CMs and covalent linkage derived from the epoxy-amine addition reactions. The chemically stable HMCSs and its integration with CMs contributed to dramatically higher stability and recyclability of bionic nanocomposites. With the fishing of osteoblast CMs integrated HQ-HMCSs, two novel potential anti-osteoporosis compounds, narcissoside and beta-ionone, were discovered from Hippophae rhamnoides L. Enhanced osteoblast proliferation, alkaline phosphatase, and mineralization levels proved their positive osteogenesis effects. Preliminary pharmacological investigation demonstrated their potential action on membrane proteins of estrogen receptor alpha and insulin-like growth factor 1. Furthermore, beta-ionone showed apparent therapeutic effects on osteogenic lesions in zebrafish. These results provide a green, stable, cost-efficient, and reliable access to rapid discovery of drug leads, which verifiably benefits the design of nanocarbon-based biocomposites with increasingly advanced functionality.


Asunto(s)
Productos Biológicos , Quitosano , Nanosferas , Norisoprenoides , Animales , Quitosano/química , Nanosferas/química , Pez Cebra , Carbono/química , Fenómenos Magnéticos
17.
Heliyon ; 9(11): e20689, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37885730

RESUMEN

In this study, bismuth ferrite nanoparticles and metal-organic framework, Cu(BDC), were prepared by microwave-assisted combustion in solid state and ultrasound-assisted method, respectively. To enhance the properties of bismuth ferrite nanoparticles and Cu(BDC), we form them as their composite through microwave and ultrasonic probe strategies. Various analyses, including FT-IR, XRD, SEM, DRS, VSM, and so on, were applied to verify the synthesis accuracy. Then, the catalytic performances of the nanoparticles and the as-prepared nanocomposites were evaluated through photocatalytic degradation of methyl orange. Furthermore, the adsorption capacity of the as-synthesized materials was assessed toward the Congo red removal from wastewater. All the results prove that the proposed nanocomposite can be an acceptable candidate for eliminating contaminants from wastewater. The electrochemical properties of bismuth ferrite, BiFeO3/Cu(BDC) nanocomposite 1, and BiFeO3/Cu(BDC) nanocomposite 2 have been studied by cyclic voltammetry.

18.
Mikrochim Acta ; 190(11): 452, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37882891

RESUMEN

Cerium ions immobilized magnetic graphite nitride material have been prepared using L-Alanyl-L-Glutamine as the new chelator. The resulting Fe3O4/g-C3N4-L-Ala-L-Gln-Ce4+, as an immobilized metal ion affinity chromatography (IMAC) sorbent, was reusable. This is due to the strong coordination interaction between L-Alanyl-L-Glutamine and cerium ions. After a series of characterizations, the magnetic nanocomposite showed high surface area, good hydrophilicity, positive electricity, and magnetic response. Fe3O4/g-C3N4-L-Ala-L-Gln-Ce4+ had high sensitivity (0.1 fmol), selectivity (α-/ß-casein/bovine serum albumin, 1:1:5000), and good recyclability (10 cycles). A total of 647 unique phosphopeptides mapped to 491 phosphoproteins were identified from A549 cell lysate by nano LC-MS analysis.


Asunto(s)
Cerio , Grafito , Quelantes/química , Fosfopéptidos/análisis , Grafito/química , Glutamina , Caseínas/química , Fenómenos Magnéticos , Iones
19.
Nanotechnology ; 34(49)2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37669630

RESUMEN

The present investigation employed a facile hydrothermal approach for the fabrication of Fe3O4/ZnO dual-functional magnetic nanocomposite. Supercapacitor and visible-light-driven photocatalytic applications of the material were explored. X-ray diffraction, Fourier transform infrared spectra, ultraviolet-visible diffuse reflectance spectra (UV-vis/DRS), field emission scanning electron microscopy (FE-SEM), energy dispersive x-ray spectroscopy, and vibrating sample magnetometer were used to analyse the nanocomposite's structural, morphological, optical, and magnetic properties. The FE-SEM analysis demonstrated that the surface morphology of Fe3O4, ZnO, and the Fe3O4/ZnO nanocomposite consisted of nanoparticles, nanoflakes, and nanoparticles adhered to the nanoflakes, respectively. The maximum specific capacitance of the electrode based on the Fe3O4/ZnO nanocomposite was measured to be 736.36 Fg-1at a scan rate of 5 mVs-1. The electrode also demonstrated remarkable cycling stability, retaining 86.5% of its capacitance even after 3000 cycles. The Fe3O4/ZnO nanocomposite was found to have an optical bandgap of 2.7 eV, an average particle size of 22.5 nm, and a saturation magnetization of 68.7 emu g-1. The photocatalysis experiment was conducted using the optimised settings, which included a pH of 7.0, a dye concentration of 30 mg l-1, a catalyst dose of 1 g l-1, and a contact time of 120 min. The Fe3O4/ZnO nanocomposite exhibited a notable degradation efficiency towards crystal violet dye upon exposure to visible light, achieving a degradation efficiency of 96.9%. This performance surpassed that of pure ZnO, which attained a degradation efficiency of 70.2%. The nanocomposite exhibited a rate constant of 2.80 × 10-2min-1, which was found to be notably higher than that of pure ZnO (0.8 × 10-2min-1), as determined through modelling (pseudo-first order linear fit). The radical scavenger experiments indicated that the superoxide radicals and hydroxyl radicals are the primary reactive species. The Fe3O4/ZnO photocatalyst can be effectively isolated using a bar magnet. Remarkably, the photocatalytic efficiency of the material remained almost entirely intact even after undergoing four cycles of recycling. In addition, this research opens up exciting new possibilities for use in fields like energy storage and pollution control.

20.
Chemosphere ; 341: 140129, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37690550

RESUMEN

The rapid and efficient mineralization of the chemotherapeutic drug busulfan (BSF) as the target pollutant has been investigated for the first time by three different heterogeneous EF systems that were constructed to ensure the continuous electro-generation of H2O2 and •OH consisting of: i) a multifunctional carbon felt (CF) based cathode composed of reduced graphene oxide (rGO), iron oxide nanoparticles and carbon black (CB) (rGO-Fe3O4/CB@CF), ii) rGO modified cathode (rGO/CB@CF) and rGO supported Fe3O4 (rGO-Fe3O4) catalyst and iii) rGO modified cathode (rGO/CB@CF) and multi walled carbon nanotube supported Fe3O4 (MWCNT-Fe3O4) catalyst. The effects of main variables, including the catalyst amount, applied current and initial pH were investigated. Based on the results, H2O2 was produced by oxygen reduction reaction (ORR) on the liquid-solid interface of both fabricated cathodes. •OH was generated by the reaction of H2O2 with the active site of ≡FeII on the surface of the multifunctional cathode and heterogeneous EF catalysts. Utilizing carbon materials with high conductivity, the redox cycling between ≡FeII and ≡FeIII was effectively facilitated and therefore promoted the performance of the process. The results demonstrated almost complete mineralization of BSF through the heterogeneous systems over a wide applicable pH range. According to the reusability and stability tests, multifunctional cathode exhibited outstanding performance after five consecutive cycles which is promising for the efficient mineralization of refractory organic pollutants. Moreover, intermediates products of BSF oxidation were identified and a plausible oxidation pathway was proposed. Therefore, this study demonstrates efficient and stable cathodes and catalysts for the efficient treatment of an anticancer active substance.


Asunto(s)
Contaminantes Ambientales , Nanocompuestos , Busulfano , Compuestos Férricos , Peróxido de Hidrógeno , Conductividad Eléctrica , Hollín , Compuestos Ferrosos
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