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1.
Int J Mol Sci ; 22(5)2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33802613

RESUMEN

This study demonstrates the rational fabrication of a magnetic composite nanofiber mesh that can achieve mutual synergy of hyperthermia, chemotherapy, and thermo-molecularly targeted therapy for highly potent therapeutic effects. The nanofiber is composed of biodegradable poly(ε-caprolactone) with doxorubicin, magnetic nanoparticles, and 17-allylamino-17-demethoxygeldanamycin. The nanofiber exhibits distinct hyperthermia, owing to the presence of magnetic nanoparticles upon exposure of the mesh to an alternating magnetic field, which causes heat-induced cell killing as well as enhanced chemotherapeutic efficiency of doxorubicin. The effectiveness of hyperthermia is further enhanced through the inhibition of heat shock protein activity after hyperthermia by releasing the inhibitor 17-allylamino-17-demethoxygeldanamycin. These findings represent a smart nanofiber system for potent cancer therapy and may provide a new approach for the development of localized medication delivery.


Asunto(s)
Benzoquinonas/farmacología , Preparaciones de Acción Retardada/farmacología , Doxorrubicina/farmacología , Lactamas Macrocíclicas/farmacología , Nanofibras/química , Neoplasias/tratamiento farmacológico , Benzoquinonas/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Preparaciones de Acción Retardada/química , Doxorrubicina/química , Liberación de Fármacos , Sinergismo Farmacológico , Compuestos Férricos/química , Humanos , Lactamas Macrocíclicas/química , Células MCF-7 , Magnetismo/métodos , Nanopartículas de Magnetita/química
2.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33807943

RESUMEN

We evaluated the effect of manganese ferrite nanoparticles (MFN) on radiosensitization and immunologic responses using the murine hepatoma cell line Hepa1-6 and the syngeneic mouse model. The clonogenic survival of Hepa1-6 cells was increased by hypoxia, while being restricted by ionizing radiation (IR) and/or MFN. Although MFN suppressed HIF-1α under hypoxia, the combination of IR and MFN enhanced apoptosis and DNA damage in Hepa1-6 cells. In the Hepa1-6 syngeneic mouse model, the combination of IR and MFN notably limited the tumor growth compared to the single treatment with IR or MFN, and also triggered more frequent apoptosis in tumor tissues than that observed under other conditions. Increased expression of PD-L1 after IR was not observed with MFN alone or the combination of IR and MFN in vitro and in vivo, and the percentage of tumor-infiltrating T cells and cytotoxic T cells increased with MFN, regardless of IR, in the Hepa1-6 syngeneic mouse model, while IR alone led to T cell depletion. MFN might have the potential to overcome radioresistance by alleviating hypoxia and strengthening antitumor immunity in the tumor microenvironment.


Asunto(s)
Carcinoma Hepatocelular/radioterapia , Compuestos Férricos/farmacología , Neoplasias Hepáticas/radioterapia , Compuestos de Manganeso/farmacología , Nanopartículas/uso terapéutico , Radiación Ionizante , Fármacos Sensibilizantes a Radiaciones/farmacología , Microambiente Tumoral/efectos de la radiación , Animales , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Compuestos Férricos/química , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/patología , Compuestos de Manganeso/química , Ratones , Nanopartículas/química , Fármacos Sensibilizantes a Radiaciones/química , Linfocitos T/inmunología , Linfocitos T/patología , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología
3.
Nat Biomed Eng ; 5(3): 252-263, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33686281

RESUMEN

Contrast agents for magnetic resonance imaging (MRI) improve anatomical visualizations. However, owing to poor image resolution in whole-body MRI, resolving fine structures is challenging. Here, we report that a nanoparticle with a polysaccharide supramolecular core and a shell of amorphous-like hydrous ferric oxide generating strong T1 MRI contrast (with a relaxivity coefficient ratio of ~1.2) facilitates the imaging, at resolutions of the order of a few hundred micrometres, of cerebral, coronary and peripheral microvessels in rodents and of lower-extremity vessels in rabbits. The nanoparticle can be synthesized at room temperature in aqueous solution and in the absence of surfactants, has blood circulation and renal clearance profiles that prevent opsonization, and leads to better imaging performance than Dotarem (gadoterate meglumine), a clinically approved gadolinium-based MRI contrast agent. The nanoparticle's biocompatibility and imaging performance may prove advantageous in a broad range of preclinical and clinical applications of MRI.


Asunto(s)
Dextranos/química , Compuestos Férricos/química , Imagen por Resonancia Magnética/métodos , Nanopartículas/química , Animales , Materiales Biocompatibles/química , Medios de Contraste/química , Gadolinio/química , Meglumina/química , Ratones , Ratones Endogámicos BALB C , Microvasos/patología , Compuestos Organometálicos/química , Tamaño de la Partícula , Polisacáridos/química , Conejos , Ratas , Ratas Sprague-Dawley
4.
J Chromatogr A ; 1643: 462071, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33761435

RESUMEN

Mixed iron hydroxides (MIHs) modified with different amino-based polymeric materials, including aminopropyltriethoxysilane, polydopamine, diaminobenzoic acid, polyaniline, and polyphenylenediamine, were comparatively investigated as sorbents for the extraction of phenol compounds. Polyphenylenediamine-modified mixed iron hydroxides (MIH@PPDA) showed high adsorption capability for most target analytes. Its ferromagnetic behavior, with a magnetization of 17.38 emu g-1, was sufficient for subsequent use in magnetic solid-phase extraction (MSPE). The functional groups, morphology, and magnetic properties of this magnetic nanomaterial were investigated using Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, X-ray diffraction, and CHN analysis. High-performance liquid chromatography with a photodiode array detector was used to quantify phenol compounds. The experimental parameters affecting the efficiency of the entire MSPE process were optimized. Good linearity in the range of 0.5-1000 µg L-1 was obtained (depended on the compound). The detection and quantitation limits varied from 0.01 to 0.3 µg L-1 and 0.03 to 0.9 µg L-1, respectively. The enrichment factors for all phenol compounds were in the range of 80-285. The precision in terms of intra- and inter-day relative standard deviations were below 5.8% and 6.2%, respectively. The developed MSPE method was applied to analyze phenol compounds in diverse samples, including soil, drinking water, and fruit. Relative recoveries of 76.7-130.1% were obtained. The MIH@PPDA magneto-polymeric sorbent exhibits good stability and is reliable for a variety of phenol compounds.


Asunto(s)
Compuestos Férricos/química , Magnetismo , Fenol/análisis , Polímeros/química , Extracción en Fase Sólida/métodos , Adsorción , Cromatografía Líquida de Alta Presión , Agua Dulce/análisis , Concentración de Iones de Hidrógeno , Límite de Detección , Fenol/aislamiento & purificación , Reproducibilidad de los Resultados , Contaminantes del Suelo/análisis
5.
Carbohydr Polym ; 260: 117777, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712133

RESUMEN

The combination of alginate, hyaluronic acid and multivalent ions have been reported to form alginate-hyaluronic acid ionic-crosslinking hydrogels for biomedical applications. However, injectable alginate-hyaluronic acid ionic-crosslinking hydrogels with satisfactory shear-thinning property have rarely been reported. In this study, we successfully developed an ionic-crosslinked alginate-hyaluronic acid hydrogel by simple assembly of alginate-hyaluronic acid mixture and Fe3+ complex. This hydrogel could fully recover within seconds after damaged, while displayed shear thinning behavior and good injectability which were contributed by the reversible and dynamic metal-ligand interactions formed via ferric ions and carboxyl groups of the polymers. Moreover, the local degradation of this hydrogel giving the hydrogel sustained ferric ions release property, of which led to potential long-term antibacterial activities against multiple types of bacteria including gram-negative Escherichia coli and gram-positive Staphylococcus aureus, as well as representative oral pathogenic bacteria Streptococcus mutans and Porphyromonas gingivalis.


Asunto(s)
Alginatos/química , Antiinfecciosos/química , Compuestos Férricos/química , Ácido Hialurónico/química , Hidrogeles/química , Animales , Antiinfecciosos/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Femenino , Compuestos Férricos/metabolismo , Humanos , Hidrogeles/farmacología , Ratones , Ratones Endogámicos BALB C , Porphyromonas/efectos de los fármacos , Reología , Piel/efectos de los fármacos , Piel/patología , Staphylococcus aureus/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos
6.
Int J Nanomedicine ; 16: 2271-2282, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33776432

RESUMEN

Background: Contrast-enhanced magnetic resonance imaging (MRI) is a powerful diagnostic tool for many diseases. In many situations, the contrasts are repeatedly administrated in order to monitor and assess the disease progression. Objective: To investigate and compare the biological effects of γ-Fe2O3 nanoparticle (NP) and gadolinium dimeglumine (Gd-DTPA) with high and multiple doses on the kidney of healthy mice. Methods: Polydextrose sorbitol carboxymethyl ether coated γ-Fe2O3 NP with hydrodynamic size of 68.2 nm and clinically applied Gd-DTPA were employed on healthy mice with the repeatedly intravenous administration of high doses. The cell viability of human umbilical vein endothelial cells (HUVEC) in high doses of these two contrast agents were measured using the xCELLigence Real-Time Cell Analysis (RTCA) S16 Instrument. The biological effects of γ-Fe2O3 NP and Gd-DTPA on the kidney were obtained using a biochemical automatic analyzer and multiple proinflammatory factor kit on the serum. Histopathological and immunohistochemistry analysis were taken on kidney tissues. Results: It showed that the proinflammatory responses elicited by the γ-Fe2O3 NPs were weaker than that by Gd-DTPA, evidenced by the relatively much lower level of IL-1ß, IL-6, IL-18, TNF-α, C-reactive protein (CRP) and Ferritin. At the same time, the γ-Fe2O3 NPs did not have the biochemical index elevated, while the Gd-DTPA did. Conclusion: The γ-Fe2O3 NPs induced weaker proinflammatory effects in reference to the Gd-DTPA, indicating better renal safety. Therefore, it is suggested that γ-Fe2O3 NPs should be safer and optional choice when repeated contrast-enhanced MRI is necessary.


Asunto(s)
Medios de Contraste/química , Compuestos Férricos/química , Gadolinio DTPA/química , Inflamación/patología , Riñón/fisiopatología , Nanopartículas/química , Animales , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Proliferación Celular , Supervivencia Celular , Ferritinas/sangre , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Riñón/patología , Imagen por Resonancia Magnética , Masculino , Ratones , Espectrometría por Rayos X , Factor de Crecimiento Transformador beta/metabolismo
7.
Food Chem ; 352: 129330, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33657486

RESUMEN

Pregnancy test strips are one of the most mature and widely used commercial lateral flow devices used to determine pregnancy. Being a simple and rapid detection method, human chorionic gonadotropin (hCG) was used with different aptamers (hCG-apt) as probes for the detection of metal ions, small organic molecules, and proteins. Quantitative detection of target analytes was achieved using a smartphone app and a portable device developed in our laboratory. The results showed detection ranges of 1 nM-1 µM, 0.1 nM-10 µM and 32 nM-500 nM for Pb2+, chloramphenicol, and ß-lactoglobulin, respectively, and the corresponding visual detection limits in dairy products were 5 nM, 1 nM and 50 nM, respectively. Based on these results, rapid detection of multiple analytes can be realized through aptamer modification, thereby broadening the application range of commercial lateral flow devices for analysis of food chemistry.


Asunto(s)
Aptámeros de Nucleótidos/metabolismo , Productos Lácteos/análisis , Compuestos Férricos/química , Análisis de los Alimentos/instrumentación , Grafito/química , Pruebas de Embarazo/instrumentación , Teléfono Inteligente , Animales , Femenino , Oro/química , Humanos , Límite de Detección , Embarazo
8.
Molecules ; 26(4)2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33578897

RESUMEN

Magnetic nanocomposites based on hydroxyapatite were prepared by a one-step process using the hydrothermal coprecipitation method to sinter iron oxides (Fe3O4 and γ-Fe2O3). The possibility of expanding the proposed technique for the synthesis of magnetic composite with embedded biologically active substance (BAS) of the 2-arylaminopyrimidine group was shown. The composition, morphology, structural features, and magnetic characteristics of the nanocomposites synthesized with and without BAS were studied. The introduction of BAS into the composite synthesis resulted in minor changes in the structural and physical properties. The specificity of the chemical bonds between BAS and the hydroxyapatite-magnetite core was revealed. The kinetics of the BAS release in a solution simulating the stomach environment was studied. The cytotoxicity of (HAP)FexOy and (HAP)FexOy + BAS composites was studied in vitro using the primary culture of human liver carcinoma cells HepG2. The synthesized magnetic composites with BAS have a high potential for use in the biomedical field, for example, as carriers for magnetically controlled drug delivery and materials for bone tissue engineering.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Compuestos Férricos/química , Neoplasias Hepáticas/tratamiento farmacológico , Nanopartículas de Magnetita/administración & dosificación , Nanocompuestos/química , Pirimidinas/química , Apoptosis , Carcinoma Hepatocelular/patología , Células Hep G2 , Humanos , Neoplasias Hepáticas/patología , Nanopartículas de Magnetita/química
9.
Food Chem ; 345: 128854, 2021 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-33601661

RESUMEN

The changes of chemical compositions and sensory characteristics of Meili rosé wine in flint, antique green and amber bottles were studied under continuous illumination for 160 days in two light sources (white fluorescent light, UV light). The results showed that light exposure caused significant changes in free sulfur dioxide content, Fe(III):Fe(II) ratio and Malvidin-3-O-glucoside content, responsible for the accelerated color evolution of Meili rosé wine during bottle storage. Some notable aroma-related changes were also observed for sensory characteristics, particularly for wines in flint bottles, boiled-like odor and oxidized odor appeared. Bottle color played a key role in preventing rosé wine from light exposure, following the order: amber bottle > green bottle > flint bottle. Besides UV light, white fluorescent light did have negative effects on rosé wine quality, considering its ubiquitous presence and long-term exposure in practice. The underlying mechanisms related to photochemical reactions in wine were further discussed.


Asunto(s)
Almacenamiento de Alimentos/métodos , Rayos Ultravioleta , Vino/análisis , Antocianinas/análisis , Color , Compuestos Férricos/química , Compuestos Ferrosos/química , Odorantes , Dióxido de Azufre/química
10.
Molecules ; 26(3)2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33525515

RESUMEN

Polymer templates play an essential role in the robust infiltration-based synthesis of functional multicomponent heterostructures with controlled structure, porosity, and composition. Such heterostructures are be used as hybrid organic-inorganic composites or as all-inorganic systems once the polymer templates are removed. Using iron oxide/alumina heterostructures formed by two-step infiltration of polystyrene-block-polyvinyl pyridine block copolymer with iron and aluminum precursors from the solution and vapor-phases, respectively, we show that the phase and morphology of iron oxide nanoparticles dramatically depend on the approach used to remove the polymer. We demonstrate that thermal and plasma oxidative treatments result in iron oxide nanoparticles with either solid or hollow morphologies, respectively, that lead to different magnetic properties of the resulting materials. Our study extends the boundaries of structure manipulations in multicomponent heterostructures synthesized using polymer infiltration synthesis, and hence their properties.


Asunto(s)
Nanopartículas/química , Nanoestructuras/química , Polímeros/química , Óxido de Aluminio/química , Compuestos Férricos/química , Magnetismo/métodos , Nanotecnología/métodos , Poliestirenos/química , Piridinas/química
11.
Int J Biol Macromol ; 172: 55-65, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33444653

RESUMEN

In this content, a green approach for the ultrasound promoted in situ immobilization of Pd NPs over biodegradable chitosan/agarose modified ferrite NP (Fe3O4@CS-Agarose/Pd) is developed. The structural and physicochemical features of the material were estimated using advanced analytical techniques like FT-IR, ICP-OES, FESEM, EDS, XRD, TEM and VSM. The magnetic material was catalytically explored in the oxidation of alcohols under ultrasonic waves. Sonication had a significant role in enhancing the catalytic performance in the alcohol's oxidation as compared to conventional heating. The heterogeneous nanocatalyst was efficiently recycled up to 10 times with nominal loss in catalytic activity. Towards the biological applications, the Fe3O4@CS-Agarose/Pd nanocomposite showed high antioxidant activities against DPPH free radicals, comparable to standard butylated hydroxytoluene (BHT). In addition, it exhibited excellent cytotoxicity in terms of % cell viability against breast adenocarcinoma (MCF7), breast carcinoma (Hs 578Bst), infiltrating ductal cell carcinoma (Hs 319.T), and metastatic carcinoma (MDA-MB-453) cell lines. The best anti-breast cancer potential of the nanocomposite was observed in Hs 319.T cell line.


Asunto(s)
Alcoholes/química , Plásticos Biodegradables/química , Neoplasias de la Mama/tratamiento farmacológico , Quitosano/química , Nanopartículas de Magnetita/administración & dosificación , Nanopartículas de Magnetita/química , Paladio/química , Sefarosa/química , Antioxidantes/química , Compuestos de Bifenilo/química , Catálisis , Línea Celular Tumoral , Femenino , Compuestos Férricos/química , Humanos , Magnetismo/métodos , Nanocompuestos/química , Oxidación-Reducción , Picratos/química , Ondas Ultrasónicas
12.
Int J Biol Macromol ; 172: 104-113, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33444655

RESUMEN

In recent days the nanomagnetic biocomposites have been evolved as sustainable green catalysts. In that context, we are prompted to design and synthesize a novel Pd NP adorned chitosan-starch dual biopolymer encapsulated core-shell type magnetic nanocomposite (Fe3O4@CS-Starch/Pd) in an eco-friendly pathway applying ultrasound irradiations. The morphological and physicochemical features of the material were determined using several advanced techniques like FT-IR, FESEM, HRTEM, EDX, atomic mapping, VSM, XRD and ICP-OES. Catalytic efficiency of the material was investigated in the ultrasound assisted classical Suzuki-Miyaura coupling towards the synthesis of diverse range of biaryl derivatives and in the catalytic reduction of 4-Nitrophenol.In both the protocols the catalyst exhibited excellent performances. Sonication had a significant role in enhancing the catalytic performances in both the reactions as compared to conventional heating. Due to super-paramagnetism, the catalyst was easily magnetically isolable and reused in 11 cycles without considerable leaching and change in reactivity.


Asunto(s)
Quitosano/química , Compuestos Férricos/química , Nanocompuestos/química , Nanopartículas/química , Nitrofenoles/química , Paladio/química , Almidón/química , Biopolímeros/química , Catálisis , Tecnología Química Verde/métodos , Magnetismo/métodos , Ondas Ultrasónicas
13.
Food Chem ; 347: 129081, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33484956

RESUMEN

Orthophosphate is endogenously present in gastrointestinal fluids and increasingly ingested as additives in processed foods. However, its effect and mechanism of action on iron bioavailability remains controversial and largely unknown. Here, at initial dissolved P/Fe ratios ((P/Fe)init) ≥ 0.6, orthophosphate completely prevents hydrolytic Fe(III) precipitation at neutral pH by mediating the formation of negatively-charged (≈-29 mV ζ-potential) ferric hydroxide-phosphate nanoparticles (Fe(OH)P-NPs) consisting of ≈3.8-nm-diameter monomers. Fe(OH)P-NPs have decreased size and Fe/P ratio with increasing (P/Fe)init. Acidic pH and balanced salts in intestinal fluid counteract orthophosphate-mediated Fe(III) solubilization by weakening colloidal stability of Fe(OH)P-NPs. Protein digests from egg white, whey, casein, and fish muscle aid Fe(III) solubilization in intestinal fluid by stabilizing Fe(OH)P-NPs with casein digest displaying the highest Fe(III)-solubilizing capacity, and in calcein-fluorescence-quenching assay, deliver nanoparticulate Fe(III) to polarized Caco-2 cells via divalent-metal-transporter-1-dependent or endocytic pathways. Overall, our study provides a new paradigm for understanding orthophosphate's role in iron bioavailability.


Asunto(s)
Compuestos Férricos/química , Nanopartículas/metabolismo , Fosfatos/química , Animales , Células CACO-2 , Caseínas/metabolismo , Proteínas de Transporte de Catión/metabolismo , Endocitosis , Compuestos Férricos/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Hierro/metabolismo , Nanopartículas/química , Solubilidad
14.
Int J Biol Macromol ; 172: 197-209, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33453250

RESUMEN

This study is the first to evaluate the effects of Iron oxides (FeOx) species and their decoration on graphene oxide/chitosan (GO/CS) composites for Cr(VI) removal and the possibility of Fe secondary pollution. Results show that Fe(III) is a better decoration material than Fe(II) and decoration through immersion-evaporation shows a higher adsorption capacity of Cr(VI) (Qe) than co-precipitation. Fe2O3-GO/CS as the only eco-friendly composite for enhanced Cr(VI) removal is further used for batch adsorption experiments, characterization, kinetics, isotherms, and thermodynamic studies. It is found that Cr(VI) removal mainly includes electrostatic attraction between Cr(VI) oxyanions and surface -NH3+ and -OH2+, and the adsorbed Cr(VI) partially reduces to Cr(III). Qe increases with the increasing initial Cr(VI) concentration, contact time, and temperature, while decreases with the increasing pH and mass and volume ratio (m/v). The coexisting ions (Cl-, NO3-, SO42-, PO43-, As, Fe, and Pb) can cause an obvious decrease of Qe. The removal efficiency (Re) and Qe are 94.3% and 83.8 mg/g, respectively under the optimal conditions. After five times of regeneration, Re is still as high as 84% and Qe drops about 2.6%. Cr(VI) adsorption is spontaneous and endothermic, which is best fitted with the Sips model, and the fitted maximum Qe is 131.33 mg/g.


Asunto(s)
Quitosano/química , Cromo/aislamiento & purificación , Compuestos Férricos/química , Grafito/química , Nanocompuestos/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Agua Potable/química , Humanos , Concentración de Iones de Hidrógeno , Cinética , Temperatura , Termodinámica , Aguas Residuales/química , Purificación del Agua/métodos
15.
Molecules ; 26(2)2021 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-33467192

RESUMEN

The aim of this work is to study the effect of the phase composition of the synthesized Fe2O3-Gd2O3 nanoparticles on the efficiency of using magnetic hyperthermia as a basis for experiments. This class of structures is one of the most promising materials for biomedical applications and magnetic resonance imaging. In the course of the study, the dynamics of phase transformations of nanoparticles Fe2O3 → Fe2O3/GdFeO3 → GdFeO3 were established depending on the annealing temperature. It has been determined that the predominance of the GdFeO3 phase in the structure of nanoparticles leads to an increase in their size from 15 to 40 nm. However, during experiments to determine the resistance to degradation and corrosion, it was found that GdFeO3 nanoparticles have the highest corrosion resistance. During the hyperthermal tests, it was found that a change in the phase composition of nanoparticles, as well as their size, leads to an increase in the heating rate of nanoparticles, which can be further used for practical purposes.


Asunto(s)
Compuestos Férricos/química , Gadolinio/química , Calor , /química , Corrosión
16.
Nanotoxicology ; 15(2): 257-275, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33503388

RESUMEN

Safety on the use of magnetic nanomaterials (MNMs) has become an active topic of research given all the recent applications of these materials in various fields. It is known that the toxicity of MNMs depends on size, shape, and surface functionalization. In this study, we evaluate the biocompatibility with different aquatic organisms of engineered MNMs-CIT with excellent aqueous dispersion and long-term colloidal stability. Primary producers (the alga Pseudokirchneriella subcapitata), primary consumers (the rotifer Lecane papuana), and predators (the fish, Danio rerio) interacted with these materials in acute and sub-chronic toxicity tests. Our results indicate that P. subcaptita was the most sensitive taxon to MNMs-CIT. Inhibition of their population growth (IC50 = 22.84 mg L-1) elicited cell malformations and increased the content of photosynthetic pigments, likely due to inhibition of cell division (as demonstrated in AFM analysis). For L. papuana, the acute exposure to MNMs shows no significant mortality. However, adverse effects such as decreased rate of population and altered swimming patterns arise after chronic interaction with MNMs. For D. rerio organisms on early life stages, their exposure to MNMs results in delayed hatching of eggs, diminished survival of larvae, altered energy resources allocation (measured as the content of total carbohydrates, lipids, and protein), and increased glucose demand. As to our knowledge, this is the first study that includes three different trophic levels to assess the effect of MNMs in aquatic organisms; furthermore, we demonstrated that these MNMs pose hazards on aquatic food webs at low concentrations (few mgL-1).


Asunto(s)
Organismos Acuáticos/efectos de los fármacos , Cloruros/toxicidad , Compuestos Férricos/toxicidad , Compuestos Ferrosos/toxicidad , Nanoestructuras/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Biomarcadores/análisis , Cloruros/química , Compuestos Férricos/química , Compuestos Ferrosos/química , Cadena Alimentaria , Larva/efectos de los fármacos , Fenómenos Magnéticos , Microalgas/efectos de los fármacos , Nanoestructuras/química , Tamaño de la Partícula , Rotíferos/efectos de los fármacos , Propiedades de Superficie , Contaminantes Químicos del Agua/química , Pez Cebra/crecimiento & desarrollo
17.
Arch Environ Contam Toxicol ; 80(1): 248-258, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33398394

RESUMEN

Arsenic contamination in drinking water is a great concern in different regions of the world as well as in India. Several technologies have been investigated to remove arsenic from water, such as coagulation and co-precipitation, ion exchange, adsorption, and reverse osmosis. In the present research, electrocoagulation with iron electrodes has been assessed as a treatment technology for arsenic removal from groundwater to reach concentrations below 0.01 mg/L (WHO limit) and which is technically effective, affordable for the local area, and easy to operate and maintain. Electrochemically generated iron is converted to hydrated ferric oxide within the contaminated water, which takes up the arsenic from water. A downstream filtration unit (sand or activated alumina) is applied to remove ferric hydroxide flocs produced during the process. The laboratory experiments were conducted in a batch reactor using iron plates as electrodes with monopolar configuration to study the effects of initial pH and electro-charge loading (ECL) on arsenic removal. The optimum operating condition was observed for an electro-charge loading of 25-30 Coulombs/L at pH 7.0 and an initial arsenic concentration of 0.2 mg/L. Two field trials were implemented in West Bengal after suitably designing the electrocoagulation system. Arsenic removal was significant (75-80%) delivering safe water with arsenic below 0.01 mg/L (acceptable limit). Passivation of the electrodes occurred during the operation and calcium-based (including iron) deposition was observed on the cathodes. Passivation is avoidable after running regular polarity reversal of the electrodes.


Asunto(s)
Arsénico/análisis , Técnicas Electroquímicas/métodos , Agua Subterránea/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Adsorción , Electrodos , Compuestos Férricos/química , India , Hierro/química , Minerales/química
18.
J Chromatogr A ; 1638: 461889, 2021 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-33485030

RESUMEN

As a typical steroid hormone drug, estradiol (E2) is also one of the most frequently detected endocrine disrupting chemicals (EDCs) in the aquatic environment. Herein, in response to the potential risk of E2 in steroid hormone pharmaceutical industry wastewater to human and wildlife, a novel carbon nanotubes / amine-functionalized Fe3O4 (CNTs/MNPs@NH2) nanocomposites with magnetic responsive have been developed for the enrichment and extraction of E2 in pharmaceutical industry wastewater, where amino-functionalized Fe3O4 magnetic nanoparticles (MNPs@NH2) were used as a magnetic source. The resultant CNTs/MNPs@NH2 possessed both the features of CNTs and desired magnetic property, enabling to rapidly recognize and separate E2 from pharmaceutical industry wastewater. Meanwhile, the CNTs/MNPs@NH2 had good binding behavior toward E2 with fast binding kinetics and high adsorption capacity, as well as exhibited satisfactory selectivity to steroidal estrogen compounds. Furthermore, the change of pH value of aqueous phase in adsorption solvent hardly affected the adsorption of E2 by CNTs/MNPs@NH2, and the adsorption capacity of E2 ranged from 19.9 to 17.2 mg g-1 in the pH range of 3.0 to 11.0, which is a latent advantage of the follow-up development method to detect E2 in pharmaceutical industry wastewater. As a result, the CNTs/MNPs@NH2 serving as a solid phase extraction medium were successfully applied to efficiently extract E2 from pharmaceutical industry wastewater. Therefore, the CNTs/MNPs@NH2 nanocomposites could be used as a potential adsorbent for removing steroidal estrogens from water. More importantly, the developed method would provide a promising solution for the monitoring and analysis of EDCs in pharmaceutical industry wastewater.


Asunto(s)
Aminas/química , Industria Farmacéutica , Estradiol/aislamiento & purificación , Compuestos Férricos/química , Nanocompuestos/química , Nanotubos de Carbono/química , Aguas Residuales/química , Adsorción , Aerobiosis , Anaerobiosis , Estradiol/análisis , Humanos , Cinética , Magnetismo , Nanocompuestos/ultraestructura , Reproducibilidad de los Resultados , Extracción en Fase Sólida , Solventes/química , Temperatura , Aguas Residuales/análisis
19.
Carbohydr Polym ; 254: 117303, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33357870

RESUMEN

Exopolysaccharides (EPS) produced by cyanobacteria are complex biomolecules of anionic nature with potential biomedical applications. In this study, the EPS produced by the Nostoc sp. strains PCC7936 and PCC7413 were characterized and evaluated as a biomaterial for new wound dressings. The addition of acetate ions to the culture medium slightly stimulated EPS production, achieving 1463.1 ± 16.0 mgL-1 (PCC7413) and 1372.1 ± 29.0 mgL-1 (PCC7936). Both EPS presented nine monosaccharide residues and a MW > 1000 kDa. The acetate addition changed the monosaccharide molar percentages. FTIR and DLS results confirmed the anionic nature and the presence of sulfate groups in both EPS, which are determinant features for biomedical applications. Both EPS at 1%(w/v) formed gels in the presence of 0.4%(w/v) FeCl3. Results obtained for MTT assay and wound healing in vitro scratch assay revealed hydrogels biocompatibility and ability to promote fibroblast migration and proliferation that was greater in PCC7936. The Nostoc EPS hydrogels presented promising properties to be applied in the treatment of skin injuries.


Asunto(s)
Materiales Biocompatibles/química , Hidrogeles/química , Monosacáridos/química , Nostoc/metabolismo , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Acetatos/química , Vendajes , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cloruros/química , Sistemas de Liberación de Medicamentos/métodos , Compuestos Férricos/química , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Células HeLa , Ácidos Hexurónicos/química , Humanos , Peso Molecular , Polisacáridos Bacterianos/aislamiento & purificación
20.
J Mater Chem B ; 9(2): 428-439, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-33367419

RESUMEN

The use of hybrid nanostructures based on magneto-luminescent properties is a promising strategy for nano-bio applications and theranostics platforms. In this work, we carried out the synthesis and functionalization of iron oxide nanocubes (IONCs) to obtain multifunctional hybrid nanostructures towards biomedical applications. The IONCs were functionalized with tetraethylorthosilicate, thenoyltrifluoroacetone-propyl-triethoxysilane and europium(iii)-dibenzoylmethane complexes to obtain the materials termed as IOCNCs@SiO2, IONCs@SiO2TTA, IONCs@SiO2TTA-Eu and IONCs@SiO2-TTA-Eu-DBM, respectively. Then, the biological interactions of these nanostructures with red blood cells - RBCs (hemolysis) and human blood plasma (protein corona formation) were evaluated. The XPS spectrocopy and EDS chemical mapping analysis showed that each domain is homogeneously occupied in the hybrid material, with the magnetic core at the center and the luminescent domain on the surface of the hybrid nanomaterial with a core@shell like structure. Futhermore, after each functionalization step, the nanomaterial surface charge drastically changed, with critical impact on RBC lysis and corona formation. While IONCs@SiO2 and IONCs@SiO2-TTA-Eu-DBM showed hemolytic properties in a dose-dependent manner, the IONCs@SiO2TTA-Eu did not present any hemolytic effect up to 300 µg mL-1. Protein corona results showed a pattern of selective adsorption of proteins with each surface of the synthesized hybrid materials. However, as a general result, a suppression of hemolysis after protein corona formation in all tests was verified. Finally, this study provides a solid background for further applications of these hybrid magneto-luminescent materials containing new surface functionalities in the emerging field of medical nanobiotechnology.


Asunto(s)
Europio/química , Compuestos Férricos/química , Nanotecnología/métodos , Corona de Proteínas/química , Humanos
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