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Postmodification of alginate-based microspheres with polyelectrolytes (PEs) is commonly used in the cell encapsulation field to control microsphere stability and permeability. However, little is known about how different applied PEs shape the microsphere morphology and properties, particularly in vivo. Here, we addressed this question using model multicomponent alginate-based microcapsules postmodified with PEs of different charge and structure. We found that the postmodification can enhance or impair the mechanical resistance and biocompatibility of microcapsules implanted into a mouse model, with polycations surprisingly providing the best results. Confocal Raman microscopy and confocal laser scanning microscopy (CLSM) analyses revealed stable interpolyelectrolyte complex layers within the parent microcapsule, hindering the access of higher molar weight PEs into the microcapsule core. All microcapsules showed negative surface zeta potential, indicating that the postmodification PEs get hidden within the microcapsule membrane, which agrees with CLSM data. Human whole blood assay revealed complex behavior of microcapsules regarding their inflammatory and coagulation potential. Importantly, most of the postmodification PEs, including polycations, were found to be benign toward the encapsulated model cells.
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Alginatos , Cápsulas , Poliaminas , Polielectrolitos , Alginatos/química , Polielectrolitos/química , Cápsulas/química , Poliaminas/química , Animales , Ratones , Humanos , MicroesferasRESUMEN
The rapid advancements in nanotechnology in the field of nanomedicine have the potential to significantly enhance therapeutic strategies for cancer treatment. There is considerable promise for enhancing the efficacy of cancer therapy through the manufacture of innovative nanocomposite materials. Metallic nanoparticles have been found to enhance the release of anticancer medications that are loaded onto them, resulting in a sustained release, hence reducing the dosage required for drug administration and preventing their buildup in healthy cells. The combination of nanotechnology with biocompatible materials offers new prospects for the development of advanced therapies that exhibit enhanced selectivity, reduced adverse effects, and improved patient outcomes. Chitosan (CS), a polysaccharide possessing distinct physicochemical properties, exhibits favorable attributes for controlled drug delivery due to its biocompatibility and biodegradability. Chitosan nanocomposites exhibit heightened stability, improved biocompatibility, and prolonged release characteristics for anticancer medicines. The incorporation of gold (Au) nanoparticles into the chitosan nanocomposite results in the manifestation of photothermal characteristics, whereas the inclusion of silver (Ag) nanoparticles boosts the antibacterial capabilities of the synthesized nanocomposite. The objective of this review is to investigate the recent progress in the utilization of Ag and Au nanoparticles, or a combination thereof, within a chitosan matrix or its modified derivatives for the purpose of anticancer drug delivery. The research findings for the potential of a chitosan nanocomposite to deliver various anticancer drugs, such as doxorubicin, 5-Fluroacil, curcumin, paclitaxel, and 6-mercaptopurine, were investigated. Moreover, various modifications carried out on the chitosan matrix phase and the nanocomposite surfaces to enhance targeting selectivity, loading efficiency, and pH sensitivity were highlighted. In addition, challenges and perspectives that could motivate further research related to the applications of chitosan nanocomposites in cancer therapy were summarized.
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Antineoplásicos , Quitosano , Oro , Nanopartículas del Metal , Nanocompuestos , Plata , Quitosano/química , Nanocompuestos/química , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/administración & dosificación , Plata/química , Humanos , Nanopartículas del Metal/química , Oro/química , Sistemas de Liberación de Medicamentos , Portadores de Fármacos/química , Neoplasias/tratamiento farmacológico , AnimalesRESUMEN
A novel bio-based catalyst was developed by in-situ forming Chromium(III) (Cr)-based metal-organic framework, MIL-101(Cr), in the presence of k-carrageenan (k-Car) and followed by a post-synthetic modification to introduce additional -SO3H functional groups into the composite structure of k-Car/MIL-101(Cr). Different analyses were conducted to confirm the successful catalyst formation. The catalyst performance was evaluated in the solid acid catalyzed dehydration of fructose to 5-hydroxymethylfurfural. The Response Surface Method (RSM) optimization determined that employing 33 wt% of the catalyst at 105 °C for 40 min resulted in a remarkable 97.8 % yield. The catalyst demonstrated suitable recyclability, maintaining its catalytic efficiency over four cycles. Comparative studies with k-Car and the non-sulfonated composite highlighted the superior activity of the catalyst, emphasizing the synergy between the k-Car, MIL-101(Cr) and the influence of -SO3H post-functionalizing on the catalytic performance.
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Fructosa , Furaldehído/análogos & derivados , Estructuras Metalorgánicas , Ácidos Sulfónicos , Fructosa/química , Carragenina , Metales , CatálisisRESUMEN
In this study, we present a novel composite material consisting of ß-cyclodextrin nanosponge and sodium alginate, used as a support for the immobilization of palladium (Pd) nanoparticles. The composite alginate-cyclodextrin nanosponge beads were prepared, taking advantage of the 3D polymeric network and ß-cyclodextrin cavity of the nanosponge. These beads exhibited excellent encapsulation capabilities for hydrophobic substrates, allowing their transfer in aqueous media. The cyclodextrin nanosponge served as a stabilizer for Pd nanoparticles and facilitated phase transfer. Additionally, the sodium alginate bead contributed to the robustness of the structure and improved the recovery and recyclability of the composite material. Comparative studies with control catalysts confirmed the beneficial effect of incorporating cyclodextrin nanosponge within alginate beads, particularly for more hydrophobic substrates. Optimization of reaction conditions revealed that employing 0.03 g of catalyst per mmol of nitroarene at 45 °C resulted in the maximum yield within 90 min. Evaluation of the substrate scope demonstrated the hydrogenation capability of various substrates with different electronic properties under the developed protocol. Notably, the nitro group was selectively reduced in substrates featuring competing functionalities. Furthermore, the recyclability and stability of the composite catalyst were confirmed, making it a promising candidate for sustainable catalysis.
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Using cyclodextrin and chitosan that are bio-based compounds, a novel bi-functional catalytic composite is designed, in which metal-organic framework encapsulated phosphomolybdic acid was incorporated in a dual chitosan-cyclodextrin nanosponge bead. The composite was characterized via XRD, TGA, ICP, BET, NH3-TPD, FTIR, FE-SEM/EDS, elemental mapping analysis and its catalytic activity was examined in alcohol oxidation and cascade alcohol oxidation-Knoevenagel condensation reaction. It was found that the designed catalyst that possess both acidic feature and redox potential could promote both reactions in aqueous media at 55 °C and various substrates with different electronic features could tolerate the aforementioned reactions to furnish the products in 75-95% yield. Furthermore, the catalyst could be readily recovered and recycled for five runs with slight loss of the catalytic activity. Notably, in this composite the synergism between the components led to high catalytic activity, which was superior to each component. In fact, the amino groups on the chitosan served as catalysts, while cyclodextrin nanosponge mainly acted as a phase transfer agent. Moreover, measurement of phosphomolybdic acid leaching showed that its incorporation in metal-organic framework and bead structure could suppress its leaching, which is considered a drawback for this compound. Other merits of this bi-functional catalyst were its simplicity, use of bio-based compounds and true catalysis, which was proved via hot filtration.
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This study explores the potential of using the carbonization of Zn-based metal-organic frameworks (Zn-MOF-5) under N2 and air to modify zinc oxide (ZnO) nanoparticle for the production of various photo and bio-active greyish-black cotton fabrics. The MOF-derived ZnO under N2 demonstrated a significantly higher specific surface area (259 m2g-1) compared to ZnO (12 m2g-1) and MOF-derived ZnO under air (41.6 m2 g-1). The products were characterized using various techniques, including FTIR, XRD, XPS, FE-SEM, TEM, HRTEM, TGA, DLS, and EDS. The tensile strength and dye degradation properties of the treated fabrics were also investigated. The results indicate that the high dye degradation capability of MOF-derived ZnO under N2 is likely due to the lower ZnO band gap energy and improvement in electron-hole pair stability. Additionally, the antibacterial activities of the treated fabrics against Staphylococcus and Pseudomonas aeruginosa were investigated. The cytotoxicity of the fabrics was studied on human fibroblast cell lines using an MTT assay. The study findings demonstrate that the cotton fabric covered with carbonized Zn-MOF under N2 is human-cell compatible while showing high antibacterial activities and stability against washing, highlighting its potential for use in developing functional textiles with enhanced properties.
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Óxido de Zinc , Humanos , Óxido de Zinc/farmacología , Zinc , Textiles , Antibacterianos/farmacología , NitrógenoRESUMEN
Injectable bioadhesive hydrogels, known for their capacity to carry substances and adaptability in processing, offer great potential across various biomedical applications. They are especially promising in minimally invasive stem cell-based therapies for treating cartilage damage. This approach harnesses readily available mesenchymal stem cells (MSCs) to differentiate into chondrocytes for cartilage regeneration. In this review, we investigate the relationship between bioadhesion and MSC differentiation. We summarize the fundamental principles of bioadhesion and discuss recent trends in bioadhesive hydrogels. Furthermore, we highlight their specific applications in conjunction with stem cells, particularly in the context of cartilage repair. The review also encompasses a discussion on testing methods for bioadhesive hydrogels and direct techniques for differentiating MSCs into hyaline cartilage chondrocytes. These approaches are explored within both clinical and laboratory settings, including the use of genetic tools. While this review offers valuable insights into the interconnected aspects of these topics, it underscores the need for further research to fully grasp the complexities of their relationship.
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In the pursuit of enhancing the catalytic potential of the Wells-Dawson (WD) polyoxometalate (POM) while addressing its solubility challenges, this study focuses on devising a sustainable catalyst that operates effectively in aqueous environments. Leveraging cyclodextrin (CD) polymer chemistry in conjunction with 3D printing technology, a CD nanosponge, recognized for its interaction with POMs and molecular shuttle attributes, is synthesized as a scaffold for WD immobilization. Through integration into a 3D-printed monolith framework, the supported WD species becomes embedded within the catalyst structure, facilitating its application. Extensive characterization encompassing X-ray diffraction, thermogravimetric analysis, Fourier transform infrared, scanning electron microscopy/energy-dispersive system, elemental mapping analysis, and compression testing confirms the structural integrity and viability of the resulting catalyst. The catalytic assessment of the developed catalyst in the Knoevenagel condensation reaction within aqueous settings demonstrates enhanced reusability attributed to the encapsulation within the 3D matrix. Notably, a hot filtration test provides empirical evidence of heterogeneous catalysis mode, further underpinning the catalyst's performance and potential for sustainable applications.
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Zinc oxide nanoparticles (ZnO NPs) have gained significant attention in the textile industry for their ability to enhance the physicochemical properties of fabrics. In recent years, there has been a growing focus on the development of ZnO-based nanomaterials and their applications for cotton and other fabrics. This review paper provides an overview of the synthesis and diverse applications of ZnO-based nanomaterials for textile fabrics, including protection against UV irradiation, bacteria, fungi, microwave, electromagnetic radiation, water, and fire. Furthermore, the study offers the potential of these materials in energy harvesting applications, such as wearable pressure sensors, piezoelectric nanogenerators, supercapacitors, and human energy harvesting. Additionally, we discuss the potential of ZnO-based nanomaterials for environmental cleaning, including water, oil, and solid cleaning. The current research in this area has focused on various materials used to prepare ZnO-based nanocomposites, such as metals/nonmetals, semiconductors, metal oxides, carbon materials, polymers, MXene, metal-organic frameworks, and layered double hydroxides. The findings of this review highlight the potential of ZnO-based nanomaterials to improve the performance of textile fabrics in a range of applications, and the importance of continued research in this field to further advance the development and use of ZnO-based nanomaterials in the textile industry.
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Nanopartículas , Óxido de Zinc , Humanos , Óxido de Zinc/química , Textiles , Nanopartículas/química , AguaRESUMEN
Multicomponent nanoparticle systems are known for their varied properties and functions, and have shown potential as gene nanocarriers. This study aims to synthesize and characterize ternary nickel-cobalt-ferrite (NiCoFe2O4) nanoparticles with the potential to serve as gene nanocarriers for cancer/gene therapy. The biogenic nanocarriers were prepared using a simple and eco-friendly method following green chemistry principles. The physicochemical properties of the nanoparticles were analyzed by X-ray diffraction, vibrating sample magnetometer, X-ray photoelectron spectroscopy, and Brunauer-Emmett-Teller. To evaluate the morphology of the nanoparticles, the field emission scanning electron microscopy with energy dispersive X-Ray spectroscopy, high-resolution transmission electron microscopy imaging, and electron tomography were conducted. Results indicate the nanoparticles have a nanoflower morphology with a mesoporous nature and a cubic spinel structure, where the rod and spherical nanoparticles became rose-like with a specific orientation. These nanoparticles were found to have minimal toxicity in human embryonic kidney 293 (HEK-293 T) cells at concentrations of 1 to 250 µg·mL-1. We also demonstrated that the nanoparticles could be used as gene nanocarriers for delivering genes to HEK-293 T cells using an external magnetic field, with optimal transfection efficiency achieved at an N/P ratio of 2.5. The study suggests that biogenic multicomponent nanocarriers show potential for safe and efficient gene delivery in cancer/gene therapy.
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Recently, developing antibacterial wound dressings based on biomaterials display good biocompatibility and the potential to accelerate wound healing. For this aim, we prepared eco-friendly and biodegradable nanofibers (NFs) based on N-(3-sulfopropyl)chitosan/ poly (ε-caprolactone) incorporated by zeolite imidazolate framework-8 nanoparticles (ZIF-8 NPs) and chamomile essential oil (MCEO) via the electrospinning technique for their efficacy as wound dressing scaffolds. Fabricated NFs were characterized and studied for their structural, morphological, mechanical, hydrophilic, and thermal stability properties. The results of scanning electron microscopy (SEM) revealed that adding the ZIF-8 NPs/ MCEO, very slightly influenced the average diameter of NFs (PCL/SPCS (90:10) with 90 ± 32 nm). The developed uniform MCEO-loaded ZIF-8/PCL/SPCS NFs displayed better cytocompatibility, proliferation, and physicochemical properties (e.g. thermal stability and mechanical properties) than neat NFs. The results of cytocompatibility, DAPI (4',6-diamidino-2-phenylindole) staining study, and SEM micrographs demonstrated that formulated NFs had promising adhesion and proliferation against normal human foreskin fibroblasts-2 (HFF-2 cell line). The prepared NFs revealed excellent antibacterial activity against both Staphylococcus aureus and Escherichia coli with inhibition of 32.3 mm and 31.2 mm, respectively. Accordingly, the newly developed antibacterial NFs hold great potential as effective biomaterials for use as an active platform in wound healing applications.
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Quitosano , Matricaria , Nanofibras , Nanopartículas , Aceites Volátiles , Humanos , Quitosano/química , Aceites Volátiles/farmacología , Nanofibras/química , Antibacterianos/farmacología , Antibacterianos/química , Cicatrización de Heridas , Poliésteres/química , Materiales Biocompatibles/química , Nanopartículas/químicaRESUMEN
This study presents the development and characterization of a nanocomposite material, consisting of thermoplastic starch (TPS) reinforced with bentonite clay (BC) and encapsulated with vitamin B2 (VB). The research is motivated by the potential of TPS as a renewable and biodegradable substitute for petroleum-based materials in the biopolymer industry. The effects of VB on the physicochemical properties of TPS/BC films, including mechanical and thermal properties, water uptake, and weight loss in water, were investigated. In addition, the surface morphology and chemical composition of the TPS samples were analyzed using high-resolution SEM microscopy and EDS, providing insight into the structure-property relationship of the nanocomposites. The results showed that the addition of VB significantly increased the tensile strength and Young's modulus of TPS/BC films, with the highest values observed for nanocomposites containing 5 php of VB and 3 php of BC. Furthermore, the release of VB was controlled by the BC content, with higher BC content leading to lower VB release. These findings demonstrate the potential of TPS/BC/VB nanocomposites as environmentally friendly materials with improved mechanical properties and controlled release of VB, which can have significant applications in the biopolymer industry.
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Nanocompuestos , Almidón , Almidón/química , Bentonita/química , Arcilla , Riboflavina , Resistencia a la Tracción , Nanocompuestos/química , Agua , VitaminasRESUMEN
Diabetes mellitus is a prevalent chronic health condition that has caused millions of deaths worldwide. Monitoring blood glucose levels is crucial in diabetes management, aiding in clinical decision making and reducing the incidence of hypoglycemic episodes, thereby decreasing morbidity and mortality rates. Despite advancements in glucose monitoring (GM), the development of noninvasive, rapid, accurate, sensitive, selective, and stable systems for continuous monitoring remains a challenge. Addressing these challenges is critical to improving the clinical utility of GM technologies in diabetes management. In this concept, cyclodextrins (CDs) can be instrumental in the development of GM systems due to their high supramolecular recognition capabilities based on the host-guest interaction. The introduction of CDs into GM systems not only impacts the sensitivity, selectivity, and detection limit of the monitoring process but also improves biocompatibility and stability. These findings motivated the current review to provide a comprehensive summary of CD-based blood glucose sensors and their chemistry of glucose detection, efficiency, and accuracy. We categorize CD-based sensors into four groups based on their modification strategies, including CD-modified boronic acid, CD-modified mediators, CD-modified nanoparticles, and CD-modified functionalized polymers. These findings shed light on the potential of CD-based sensors as a promising tool for continuous GM in diabetes mellitus management.
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Cationic polysaccharides are capable of forming polyplexes with nucleic acids and are considered promising polymeric gene carriers. The objective of this study was to evaluate the transfection efficiency and cytotoxicity of N-[(2-hydroxy-3-trimethylammonium)propyl] chitosan salt (HTCS), a quaternary ammonium derivative of chitosan (CS), which benefits from non-ionizable positive charges. In this work, HTCS with a full quaternization of amino groups and a molar mass of 130,000 g·mol-1 was synthesized to use for delivery of a plasmid encoding the interleukin-12 (IL-12) gene. Thus, a polyplex based on HTCS and the IL-12 plasmid was prepared and then was characterized in terms of particle size, zeta potential, plasmid condensation ability, and protection of the plasmid against enzymatic degradation. We showed that HTCS was able to condense the IL-12 plasmid by the formation of polyplexes in the range of 74.5 ± 0.75 nm. The level of hIL-12 production following the transfection of the cells with HTCS polyplexes at a C/P ratio of 8:1 was around 4.8- and 2.2-fold higher than with CS and polyethylenimine polyplexes, respectively. These findings highlight the role of HTCS in the formation of polyplexes for the efficient delivery of plasmid DNA.
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This study is focused on enhancing the stability of mechanical and chemical properties of thermoplastic starch (TPS) by dual crosslinking strategy through melt processing conditions. The dually crosslinked TPS was prepared by in situ reaction of starch, glycerol, and epichlorohydrin (ECH), resulting in both noncovalent and covalent bond formation. The TPS was characterized by tensile testing, dynamic mechanical analysis (DMTA), rheology, and solubility in water. A substantial increase in tensile strength, Young's modulus, insoluble portion, and stability in water for dually crosslinked TPS was observed in comparison with conventional TPS. The rheology results indicated that the ECH induced the formation of 3D networks and significantly limited the chain mobility of the melted TPS, resulting in an extended relaxation process, which was also verified by DMTA. The suggested strategy avoids any chemical modification pretreatment of starch for introducing covalent bonds into TPS before one-step mixing using the melt processing technique.
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Fabrication of porous materials with a high surface area affords a great interest to achieve a system with a prolonged drug release manner. In this context, the subject of this work is to describe a novel green one-pot synthesis route for the growth of metal-organic framework (MOF) from zinc metal (Zn) and 1, 4-benzene dicarboxylic acid (BDC) in the vicinity of the carboxymethyl cellulose (CMC), which homogeneously confined in the biopolymeric chains. The synthesized Zn (BDC)@CMC was characterized and confirmed using different analyses. N2 adsorption/desorption isotherms determined the mean diameter of pore size of about 2.3993 nm. Ibuprofen (IBU) as a model drug was highly loaded to the Zn(BDC)@CMC by immersing in the drug solution; 50.95%. The in vitro IBU release study indicated that the Zn(BDC)@CMC has more attractive performances than pristine Zn(BDC). The IBU release occurred via the Fickian mechanism. Isotherm studies showed that the IBU adsorption on obeys from Langmuir isotherm; R2 0.9623. The MTT results revealed the HEK 293A cell viability of higher than 90% for Zn(BDC)@CMC that confirms its cytocompatibility. Overall, obtained results confirm the functionality of CMC biopolymer for in situ growth of MOF in the presence of it due to having the reactive nature.
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Carboximetilcelulosa de Sodio/química , Portadores de Fármacos/síntesis química , Estructuras Metalorgánicas/síntesis química , Zinc/química , Antiinflamatorios no Esteroideos/administración & dosificación , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/toxicidad , Células HEK293 , Humanos , Ibuprofeno/administración & dosificación , Estructuras Metalorgánicas/toxicidadRESUMEN
For stopping long-time harmful bacterial infection, designing a drug carrier with a highly prolonged release profile is a promising approach that is of interest to different biomedical areas. The subject of this work is to synthesis a novel carrier system through coordination of MIL-88(Fe) to carboxymethyl cellulose (CMC) for enhancing interaction between drug and carrier. We established an ultrasound-assisted synthetic method for in situ synthesis of MIL-88(Fe) in the presence of CMC resulting in CMC/MIL-88(Fe) composite. The CMC/MIL-88(Fe) was loaded with a high amount of Tetracycline (TC) by immersion of carrier to the TC aqueous solution. The release profile in the simulated physiological conditions, pH 7.4, revealed a low initial burst release followed by a sustained and prolonged release over 384 h. The in vitro cytotoxicity of CMC/MIL-88(Fe) against Human skin fibroblast (HFF-1) cells was calculated by MTT assay and showed a good cytocompatibility. The antibacterial activity was found for TC-loaded CMC/MIL-88(Fe) toward both E. coli and S. aureus with MIC 64 mg·ml-1.
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Antibacterianos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Carboximetilcelulosa de Sodio/farmacología , Estructuras Metalorgánicas/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Infecciones Bacterianas/genética , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/patología , Carboximetilcelulosa de Sodio/síntesis química , Carboximetilcelulosa de Sodio/química , Preparaciones de Acción Retardada , Portadores de Fármacos/química , Portadores de Fármacos/farmacología , Liberación de Fármacos/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/patogenicidad , Fibroblastos/efectos de los fármacos , Humanos , Estructuras Metalorgánicas/síntesis química , Estructuras Metalorgánicas/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/patogenicidad , Tetraciclina/química , Tetraciclina/farmacologíaRESUMEN
By industrialization, management of water resources is known as one of the most challenging issues for human society due to the presence of various contaminants such as oil, azo dyes, and micropollutants in water. The treatment of wastewaters containing more than one type of pollutants via a single-step process cannot be performed by a simple adsorption process. In this study, by combining the advantages of superparamagnetic iron oxide, carboxymethyl-ß-cyclodextrin polymer, and N-heterocyclic palladium complex, a versatile bi-functionalized iron oxide nanoadsorbent [Fe3O4@CM-ß-CDP@Tet-Pd] was fabricated for the capture of toxic dyes in wastewater. The structure of nanoadsorbent was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, and vibrating sample magnetometer analysis. Afterward, the catalytic activity of the synthesized nanoadsorbent was examined in the aqueous solution of sodium borohydride as the reducing agent for rhodamine B, methylene blue, 4-nitrophenol, Metanil yellow, and Eosin Y. The UV-vis spectroscopy was used to monitor the catalytic activity of the [Fe3O4@CM-ß-CDP@Tet-Pd] in an aqueous medium. The nanoadsorbent was successfully recovered and re-used six times, without remarkable loss in its catalytic activity. These results showed that the combination of iron oxide nanoparticles with carboxymethyl-ß-cyclodextrin polymer provides a promising well-performed and easily recyclable nanoadsorbent for dye uptake and wastewater treatment.
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Purificación del Agua , beta-Ciclodextrinas , Compuestos Férricos , Humanos , Hierro , PaladioRESUMEN
Conductive polymer composites (CPC) from renewable resources exhibit many interesting characteristics due to their biodegradability and conductivity changes under mechanical, thermal, chemical, or electrical stress. This study is focused on investigating the physical properties of electroconductive thermoplastic starch (TPS)-based composites and changes in electroconductive paths during cyclic deformation. TPS-based composites filled with various carbon black (CB) contents were prepared through melt processing. The electrical conductivity and physicochemical properties of TPS-CB composites, including mechanical properties and rheological behavior, were evaluated. With increasing CB content, the tensile strength and Young's modulus were found to increase substantially. We found a percolation threshold for the CB loading of approximately 5.5 wt% based on the rheology and electrical conductivity. To observe the changing structure of the conductive CB paths during cyclic deformation, both the electrical conductivity and mechanical properties were recorded in parallel using online measurements. Moreover, the instant electrical conductivity measured online during mechanical deformation of the materials was taken as the parameter indirectly describing the structure of the conductive CB network. The electrical conductivity was found to increase during five runs of repeated cyclic mechanical deformations to constant deformation below strain at break, indicating good recovery of conductive paths and their new formation.
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In this study, a simple and green strategy was reported to prepare bimetallic nanoparticles (NPs) by the combination of zinc oxide (ZnO) and copper oxide (CuO) using Sambucus nigra L. extract. The physicochemical properties of these NPs such as crystal structure, size, and morphology were studied by X-ray diffraction (XRD), field emission gun scanning electron microscopy (FEG-SEM), and transmission electron microscopy (TEM). The results suggested that these NPs contained polygonal ZnO NPs with hexagonal phase and spherical CuO NPs with monoclinic phase. The anticancer activity of the prepared bimetallic NPs was evaluated against lung and human melanoma cell lines based on MTT assay. As a result, the bimetallic ZnO/CuO NPs exhibited high toxicity on melanoma cancer cells while their toxicity on lung cancer cells was low.