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1.
Environ Sci Pollut Res Int ; 28(3): 3455-3464, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32918686

RESUMO

Recently, extensive researches were performed on carbon dioxide (CO2) capture using nano solvents. In this study, three different modified magnetic nanoparticles (NPs), including Fe3O4-Proline (Fe3O4-P), Fe3O4-Lysine (Fe3O4-L), and Fe3O4@SiO2-NH2 NPs were produced to alter and enhance the properties of Fe3O4 NPs for CO2 capture in sulfinol-M as a base solvent. CO2 capture experiments were carried out in a high-pressure batch apparatus in which CO2 absorbed into sulfinol/nano-sulfinol. The influences of NP type, NP loading, and gas phase pressure on CO2 capture were studied. Based on the obtained results, Fe3O4-L and Fe3O4@SiO2-NH2 NPs are notably capable on increasing the CO2 capture capacity of sulfinol-M, and they improved CO2 capture up to 6.3% and 13.36% as compared with the base fluid. Moreover, experiments indicated that all nanosolutions have higher CO2 capture efficiency at higher pressures. Eventually, the effect of NPs stability on CO2 capture was investigated and discussed.


Assuntos
Óxido Ferroso-Férrico , Nanopartículas de Magnetita , Aminas , Dióxido de Carbono , Dióxido de Silício , Solventes
2.
Chemosphere ; 265: 129054, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33280845

RESUMO

In this study, an innovative magnetic demulsifier (MD) was prepared by grafting a silica layer onto the surface of the Fe3O4 magnetic nanoparticles (MNPs) using the modified Stober process. The MD was characterized using various analytical techniques (XRD, FTIR, TGA, TEM, VSM, etc.) and employed to recover oil from O/W emulsion, which were then regenerated and recycled several times. The effects of magnetic demulsifier dosage (MDdose), the concentration of oil (Coil), pH, the concentration of the surfactant (Csur), and separation time (tsep) on the demulsification efficiency (%ηdem), and the percentage of oil recovered (%Roil) were evaluated. An excellent %ηdem ≥ 90% was achieved Coil in the range 50-2000 mg/L. Using an MDdose as low as 10 mg/L attained a %ηdem in the range of 93%-94.3% for O/W mixtures with Coil < 2000 mg/L, which slightly decreased to ∼90% for higher concentrations. The reported %Roil (p-value <0.05) was >90 ± 0.1 for tests carried out with pH ≤ 7 and Csur ≤ 0.1 g/L and declined at higher pH and Csur to % 86.5 due to the increase in emulsion stability. The developed MD exhibited high recyclability at an effective and stable %Roil and %ηdem of ∼90% and 86.4% after 9 cycles, respectively. Demulsification process best fits the combined Langmuir-Freundlich (L-F) isotherm with highest adsorption capacity (Qmax) of 186.0 ± 5 mgoil/gMD compared to 86.0 ± 5 mgoil/gMD for Fe3O4, which is 1.1 folds greater than Qmax reported in the literature for other demulsifiers.


Assuntos
Nanopartículas de Magnetita , Adsorção , Emulsões , Dióxido de Silício , Água
3.
Food Chem ; 338: 127812, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32861133

RESUMO

Here, we describe DNA enrichment of the zein gene from maize using pyrrolidinyl peptide nucleic acid (PNA) immobilized on a magnetic solid support as a capture element. Magnetite nanoparticles (MNP) with a capacity of 373 pmolPNA/mg and coated with poly(N-acryloylglycine) (PNAG) showed a good response to magnetic field. The PNA probe immobilized on the MNP discriminated between non-complementary and complementary DNA using fluorophore-tagged DNA as a model. We applied this system for the enrichment of the zein gene from maize in eight cereal product samples. After DNA desorption from the MNP, and its amplification via polymerase chain reaction (PCR), gel electrophoresis indicated that only cereal samples containing the zein gene from maize yielded positive results, indicating a high binding specificity between the PNA used and the complementary DNA. This PNA-functionalized MNP is potentially useful as an effective nano-solid support for DNA enrichment from other samples.


Assuntos
DNA de Plantas/análise , Nanopartículas de Magnetita/química , Ácidos Nucleicos Peptídicos/química , Zea mays/genética , Zeína/genética , DNA Complementar/análise , Grão Comestível/genética , Eletroforese , Corantes Fluorescentes/química , Fenômenos Magnéticos , Reação em Cadeia da Polimerase , Espectrometria de Fluorescência
4.
Chemosphere ; 262: 127872, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32791370

RESUMO

Magnetite nanoparticles (Fe3O4 NPs) was firstly used to enhance pollutants removal during coal gasification wastewater (CGW) treatment in anaerobic digestion (AD) system. Bench-scale results revealed that 200 mg/L and 20-40 nm of Fe3O4 NPs addition resulted in a maximum removal capacity of total phenol (TPh) at a temperature of 36 °C and hydraulic retention time (HRT) of 36 h. Meanwhile, Fe3O4 NPs addition reduced the oxidation reduction potential (ORP) values and biological toxicity, and enhanced the stability of AD system. Pilot-scale results showed that the TPh and chemical oxygen demand (COD) removal efficiency (53% and 49%) were obtained with the optimal dosage of Fe3O4 NPs. Moreover, electron nanowires may be established with Fe3O4 NPs assisted to perform direct interspecies electron transfer (DIET) among Geobacter, Pseudomonas and Methanosaeta species, and finally enhanced the pollutants removal efficiency.


Assuntos
Resíduos Industriais , Nanopartículas de Magnetita/química , Indústria de Petróleo e Gás , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Carvão Mineral , Elétrons , Fenol , Fenóis , Pseudomonas , Águas Residuárias
5.
Chemosphere ; 263: 128048, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297061

RESUMO

Anaerobic decolorization of azo dyes has been evidenced to be an economical and effective pretreatment method, but its generally limited by the low decolorization efficiency, especially for biodecolorization sulfonated azo dyes. In this study, magnetite nanoparticles (MNPs) as a conductive material, was coupled into anaerobic system for enhancing decolorization of sulfonated azo dyes, i.e., methyl orange (MO), with technology feasibility and system stability emphasized. The results showed that the anaerobic decolorization capacity was significantly enhanced with addition of MNPs (at dose of 1 g/L), where the efficiencies of MO decolorization and aromatic amines formation were as high as 97.28 ± 0.78 % and 99.44 ± 0.25%, respectively. In addition, both electron transport system activity and sludge conductivity were also significantly improved, suggesting that a direct extracellular electron transfer had been successfully established via MNPs as RMs. Under continuous-flow experiments, addition of MNPs not only improved anaerobic system resistance environmental stress (e.g., high MO concentration, low hydraulic retention time and low co-substance concentration) but also accelerated sludge granulation. The relative abundance of functional species related to dissimilatory iron reduction and MO biodegradation were also enriched under MNPs stimulation. The observed long-term stable performance suggests the full-scale application potential of this coupled system for treatment of wastewater containing sulfonated azo dyes.


Assuntos
Corantes , Nanopartículas de Magnetita , Anaerobiose , Compostos Azo , Transporte de Elétrons , Elétrons
6.
Water Sci Technol ; 82(11): 2432-2445, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33339797

RESUMO

Three main parameters affecting TiO2/SiO2/Fe3O4 nanoparticles activity in photocatalytic degradation of methyl orange were investigated using response surface methodology (SRM). Precipitation method and sol-gel technique were used to prepare SiO2/Fe3O4 electromagnetic composite support and TiO2/SiO2/Fe3O4 photocatalytically active nanoparticles. The specific surface area, pore volume, and average pore size of the synthesized nanoparticles were respectively equal to 56 m2/g, 0.12 cm3/g and 9.4 nm. The point of zero charge (PZC) of the catalyst was measured to be 5.9. The maximum and minimum photocatalytic degradation of methyl orange using the synthesized nanoparticles were 100% and 30%, respectively. A linear model was fitted to the obtained results with R2adjusted equal to 0.87. The results of analysis of variance (ANOVA) revealed that catalyst concentration, reaction media pH and aeration rate were significantly affected the photocatalytic activity. Optimization was performed considering photocatalytic activity as the main objective functions. In order to maximize photocatalytic activity, catalyst loading, reaction media pH and aeration rate were respectively adjusted to 2,000 ppm, 3 and 2.5 L/min, which resulted in total methyl orange removal. Considering promising photocatalytic activity of TiO2/SiO2/Fe3O4 along with core-sell nanocomposite separation performance led us to propose this photocatalyst as an alternative solution for treating waste waters.


Assuntos
Nanopartículas de Magnetita , Poluentes Químicos da Água , Compostos Azo , Dióxido de Silício , Titânio
7.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(5): 786-792, 2020 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-33140601

RESUMO

As drug carriers, magnetic nanoparticles can specifically bind to tumors and have the potential for targeted therapy. It is of great significance to explore non-invasive imaging methods that can detect the distribution of magnetic nanoparticles. Based on the mechanism that magnetic nanoparticles can generate ultrasonic waves through the pulsed magnetic field excitation, the sound pressure wave equation containing the concentration information of magnetic nanoparticles was derived. Using the finite element method and the analytical solution, the consistent transient pulsed magnetic field was obtained. A three-dimensional simulation model was constructed for the coupling calculation of electromagnetic field and sound field. The simulation results verified that the sound pressure waveform at the detection point reflected the position of magnetic nanoparticles in biological tissue. Using the sound pressure data detected by the ultrasonic transducer, the B-scan imaging of the magnetic nanoparticles was achieved. The maximum error of the target area position was 1.56%, and the magnetic nanoparticles regions with different concentrations were distinguished by comparing the amplitude of the boundary signals in the image. Studies in this paper indicate that B-scan imaging can quickly and accurately obtain the dimensional and positional information of the target region and is expected to be used for the detection of magnetic nanoparticles in targeted therapy.


Assuntos
Nanopartículas de Magnetita , Acústica , Simulação por Computador , Magnetismo , Tomografia
8.
Sci Rep ; 10(1): 19004, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33149153

RESUMO

Ecuador is one of the most affected countries, with the coronavirus disease 2019 (COVID-19) infection, in Latin America derived from an ongoing economic crisis. One of the most important methods for COVID-19 detection is the use of techniques such as real time RT-PCR based on a previous extraction/purification of RNA procedure from nasopharyngeal cells using functionalized magnetic nanoparticles (MNP). This technique allows the processing of ~ 10,000 tests per day in private companies and around hundreds per day at local Universities guaranteeing to reach a wide range of the population. However, the main drawback of this method is the need for specialized MNP with a strong negative charge for the viral RNA extraction to detect the existence of the SARS-CoV-2 virus. Here we present a simplified low cost method to produce 10 g of nanoparticles in 100 mL of solution that was scaled to one litter by parallelizing the process 10 times in just two days and allowing for the possibility of making ~ 50,000 COVID-19 tests. This communication helps in reducing the cost of acquiring MNP for diverse biomolecular applications supporting developing country budgets constraints and chemical availability specially during the COVID-19 International Health Emergency.


Assuntos
Técnicas de Laboratório Clínico/métodos , Custos e Análise de Custo , Nanopartículas de Magnetita/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Infecções por Coronavirus/diagnóstico , Países em Desenvolvimento , Humanos , Nanopartículas de Magnetita/economia , RNA Viral/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa/economia
9.
Int J Nanomedicine ; 15: 7923-7936, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116509

RESUMO

Introduction: We present a multimodal nanoplatforms for the treatment of hepatocellular carcinoma (HCC) in vitro. The nanoplatforms are based on polydopamine (PDA)-coated magnetite nanoparticles (NPs) and spheres (sMAG) with PAMAM dendrimers and functionalized with NHS-PEG-Mal (N-hydroxysuccinimide-polyethylene glycol-maleimide) linker, which allows their functionalization with a folic acid derivative. The nanomaterials bearing a folic acid-targeting moiety show high efficiency in killing cancer cells in the dual chemo- and photothermal therapy (CT-PTT) of the liver cancer cells in comparison to modalities performed separately. Materials and Methods: All materials are characterized in detail with transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potential and magnetic measurements. Also, photothermal properties were determined under irradiation of nanoparticles with laser beam of 2 W/cm2. The nontoxicity of nanoparticles with doxorubicin and without was checked by WST and LIVE/DEAD assay. Those tests were also used to evaluate materials bearing folic acid and anticancer drug in combined chemo- and photothermal therapy of HCC. Further, the generation of reactive oxygen species profile was also evaluated using flow cytometry test. Results: Both NPs and sMAG showed high photothermal properties. Nevertheless, the higher photothermal response was found for magnetic spheres. Materials of concentration above 10 µg/mL reveal that their activity was comparable to free doxorubicin. It is worth highlighting that a functionalized magnetic sphere with DOXO more strongly affected the HepG2 cells than smaller functionalized nanoparticles with DOXO in the performed chemotherapy. This can be attributed to the larger size of particles and a different method of drug distribution. In the further stage, both materials were assessed in combined chemo- and photothermal therapy (CT-PTT) which revealed that magnetic spheres were also more effective in this modality than smaller nanoparticles. Conclusion: Here, we present two types of nanomaterials (nanoparticles and spheres) based on polydopamine and PAMAM dendrimers g.5.0 functionalized with NHS-PEG-Mal linker terminated with folic acid for in vitro hepatocellular carcinoma treatment. The obtained materials can serve as efficient agents for dual chemo- and photothermal therapy of HCC. We also proved that PDA-coated magnetic spheres were more efficient in therapies based on near-infrared irradiation because determined cell viabilities for those materials are lower than for the same concentrations of nanomaterials based on small magnetic nanoparticles.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/terapia , Portadores de Fármacos/química , Neoplasias Hepáticas/terapia , Nanopartículas de Magnetita/química , Fototerapia , Animais , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Terapia Combinada , Dendrímeros/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Humanos , Indóis/química , Neoplasias Hepáticas/tratamento farmacológico , Polietilenoglicóis/química , Polímeros/química
10.
Int J Nanomedicine ; 15: 7979-7993, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116513

RESUMO

Background: Both magnetic nanoparticles (MNPs) and exosomes derived from bone mesenchymal stem cells (BMSC-Exos) have been reported to improve wound healing. In this study, novel exosomes (mag-BMSC-Exos) would be fabricated from BMSCs with the stimulation of MNPs and a static magnetic field (SMF) to further enhance wound repair. Methods: Mag-BMSC-Exos, namely, exosomes derived from BMSCs preconditioned with Fe3O4 nanoparticles and a SMF, together with BMSC-Exos were both first isolated by ultracentrifugation, respectively. Afterwards, we conducted in vitro experiments, including scratch wound assays, transwell assays, and tube formation assays, and established an in vivo wound healing model. The miRNA expression profiles were compared between BMSC-Exos and mag-BMSC-Exos to detect the potential mechanism of improving wound healing. At last, the function of exosomal miR-21-5p during wound healing was confirmed by utilizing a series of gain- and loss-of-function experiments in vitro. Results: The optimal working magnetic condition was 50 µg/mL Fe3O4 nanoparticles combined with 100 mT SMF. In vitro, mag-BMSC-Exo administration promoted proliferation, migration and angiogenesis to a greater extent than BMSC-Exo administration. Local transplantation of mag-BMSC-Exos into rat skin wounds resulted in accelerated wound closure, narrower scar widths and enhanced angiogenesis compared with BMSC-Exo transplantation. Notably, miR-21-5p was found to be highly enriched in mag-BMSC-Exos and served as a critical mediator in mag-BMSC-Exo-induced regulatory effects through inhibition of SPRY2 and activation of the PI3K/AKT and ERK1/2 signaling pathways. Conclusion: Mag-BMSC-Exos can further enhance wound healing than BMSC-Exos by improving angiogenesis and fibroblast function, and miR-21-5p upregulation in mag-BMSC-Exos might be the potential mechanism. This work offers an effective and promising protocol to improve wound healing in clinic.


Assuntos
Exossomos/efeitos dos fármacos , Exossomos/metabolismo , Campos Magnéticos , Nanopartículas de Magnetita , Células-Tronco Mesenquimais/citologia , MicroRNAs/genética , Regulação para Cima , Cicatrização , Animais , Fibroblastos/citologia , Fibroblastos/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas do Tecido Nervoso/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Ratos
11.
Nat Commun ; 11(1): 5421, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33110072

RESUMO

The clinical applications of magnetic hyperthermia therapy (MHT) have been largely hindered by the poor magnetic-to-thermal conversion efficiency of MHT agents. Herein, we develop a facile and efficient strategy for engineering encapsulin-produced magnetic iron oxide nanocomposites (eMIONs) via a green biomineralization procedure. We demonstrate that eMIONs have excellent magnetic saturation and remnant magnetization properties, featuring superior magnetic-to-thermal conversion efficiency with an ultrahigh specific absorption rate of 2390 W/g to overcome the critical issues of MHT. We also show that eMIONs act as a nanozyme and have enhanced catalase-like activity in the presence of an alternative magnetic field, leading to tumor angiogenesis inhibition with a corresponding sharp decrease in the expression of HIF-1α. The inherent excellent magnetic-heat capability, coupled with catalysis-triggered tumor suppression, allows eMIONs to provide an MRI-guided magneto-catalytic combination therapy, which may open up a new avenue for bench-to-bed translational research of MHT.


Assuntos
Proteínas de Bactérias/química , Hipertermia Induzida , Nanocompostos/administração & dosagem , Neoplasias/terapia , Animais , Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Catálise , Compostos Férricos/química , Humanos , Hipertermia Induzida/instrumentação , Hipertermia Induzida/métodos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Magnetismo , Nanopartículas de Magnetita/administração & dosagem , Nanopartículas de Magnetita/química , Masculino , Camundongos Endogâmicos BALB C , Myxococcus xanthus/genética , Myxococcus xanthus/metabolismo , Nanocompostos/química , Neoplasias/genética , Neoplasias/metabolismo , Nanomedicina Teranóstica
12.
Int J Nanomedicine ; 15: 8201-8215, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33122906

RESUMO

Background: One major limitation of cancer chemotherapy is a failure to specifically target a tumor, potentially leading to side effects such as systemic cytotoxicity. In this case, we have generated a cancer cell-targeting nanoparticle-liposome drug delivery system that can be activated by near-infrared laser light to enable local photo-thermal therapy and the release of chemotherapeutic agents, which could achieve combined therapeutic efficiency. Methods: To exploit the magnetic potential of iron oxide, we prepared and characterized citric acid-coated iron oxide magnetic nanoparticles (CMNPs) and encapsulated them into thermo-sensitive liposomes (TSLs). The chemotherapeutic drug, doxorubicin (DOX), was then loaded into the CMNP-TSLs, which were coated with an antibody against the epidermal growth factor receptor (EGFR), cetuximab (CET), to target EGFR-expressing breast cancer cells in vitro and in vivo studies in mouse model. Results: The resulting CET-DOX-CMNP-TSLs were stable with an average diameter of approximately 120 nm. First, the uptake of TSLs into breast cancer cells increased by the addition of the CET coating. Next, the viability of breast cancer cells treated with CET-CMNP-TSLs and CET-DOX-CMNP-TSLs was reduced by the addition of photo-thermal therapy using near-infrared (NIR) laser irradiation. What is more, the viability of breast cancer cells treated with CMNP-TSLs plus NIR was reduced by the addition of DOX to the CMNP-TSLs. Finally, photo-thermal therapy studies on tumor-bearing mice subjected to NIR laser irradiation showed that treatment with CMNP-TSLs or CET-CMNP-TSLs led to an increase in tumor surface temperature to 44.7°C and 48.7°C, respectively, compared with saline-treated mice body temperature ie, 35.2°C. Further, the hemolysis study shows that these nanocarriers are safe for systemic delivery. Conclusion: Our studies revealed that a combined therapy of photo-thermal therapy and targeted chemotherapy in thermo-sensitive nano-carriers represents a promising therapeutic strategy against breast cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/terapia , Lipossomos/administração & dosagem , Nanopartículas de Magnetita/administração & dosagem , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Cetuximab/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Receptores ErbB/metabolismo , Feminino , Compostos Férricos/química , Humanos , Hipertermia Induzida , Lipossomos/química , Nanopartículas de Magnetita/química , Camundongos Endogâmicos BALB C , Temperatura , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1795-1798, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018347

RESUMO

This contribution deals with the detection and imaging of magnetic modulated nanoparticles by means of ultra-wideband sensing. We performed phantom measurements in a practical measurement setup where the magnetic nanoparticles are modulated by a static and a low periodic changing external magnetic field. We investigated the influence of the modulation type of the polarizing magnetic field on both, detectability and imaging of magnetic nanoparticles. We can conclude that both modulations generate a sufficient contrast in order that the nanoparticles were detected at the correct position in a three-dimensional volume. The imaging results, including 32 channels, indicate that the two state (ON/OFF) modulation of the magnetic field under constant environmental conditions shows better results compared to a sinusoidal excitation of the magnetic field.


Assuntos
Nanopartículas de Magnetita , Imageamento de Micro-Ondas , Campos Magnéticos , Magnetismo , Micro-Ondas
14.
Anticancer Res ; 40(11): 5989-5994, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33109536

RESUMO

Glioblastoma (GB) is a highly aggressive and infiltrative brain tumor characterized by poor outcomes and a high rate of recurrence despite maximal safe resection, chemotherapy, and radiation. Superparamagnetic iron oxide nanoparticles (SPIONs) are a novel tool that can be used for many applications including magnetic targeting, drug delivery, gene delivery, hyperthermia treatment, cell tracking, or multiple simultaneous functions. SPIONs are studied as a magnetic resonance imaging tumor contrast agent by targeting tumor cell proteins or tumor vasculature. Drug delivery to GB tumor has been targeted with SPIONs in murine models. In addition to targeting tumor cells for imaging or drug-delivery, SPION has also been shown to be effective at targeting for hyperthermia. Along with animal models, human trials have been conducted for a number of different modes of SPION utilization, with important findings and lessons for further preclinical and clinical experiments. SPIONs are opening up several new avenues for monitoring and treatment of GB tumors; here, we review the current research and a variety of possible clinical applications.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Nanopartículas de Magnetita/uso terapêutico , Animais , Neoplasias Encefálicas/diagnóstico por imagem , Ensaios Clínicos como Assunto , Meios de Contraste/química , Sistemas de Liberação de Medicamentos , Glioblastoma/diagnóstico por imagem , Humanos
15.
Environ Res ; 191: 110139, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32888951

RESUMO

Fine particulate air pollution (PM2.5) exposures are linked with Alzheimer's and Parkinson's diseases (AD,PD). AD and PD neuropathological hallmarks are documented in children and young adults exposed lifelong to Metropolitan Mexico City air pollution; together with high frontal metal concentrations (especially iron)-rich nanoparticles (NP), matching air pollution combustion- and friction-derived particles. Here, we identify aberrant hyperphosphorylated tau, ɑ synuclein and TDP-43 in the brainstem of 186 Mexico City 27.29 ± 11.8y old residents. Critically, substantia nigrae (SN) pathology seen in mitochondria, endoplasmic reticulum and neuromelanin (NM) is co-associated with the abundant presence of exogenous, Fe-, Al- and Ti-rich NPs.The SN exhibits early and progressive neurovascular unit damage and mitochondria and NM are associated with metal-rich NPs including exogenous engineered Ti-rich nanorods, also identified in neuroenteric neurons. Such reactive, cytotoxic and magnetic NPs may act as catalysts for reactive oxygen species formation, altered cell signaling, and protein misfolding, aggregation and fibril formation. Hence, pervasive, airborne and environmental, metal-rich and magnetic nanoparticles may be a common denominator for quadruple misfolded protein neurodegenerative pathologies affecting urbanites from earliest childhood. The substantia nigrae is a very early target and the gastrointestinal tract (and the neuroenteric system) key brainstem portals. The ultimate neural damage and neuropathology (Alzheimer's, Parkinson's and TDP-43 pathology included) could depend on NP characteristics and the differential access and targets achieved via their portals of entry. Thus where you live, what air pollutants you are exposed to, what you are inhaling and swallowing from the air you breathe,what you eat, how you travel, and your occupational longlife history are key. Control of NP sources becomes critical.


Assuntos
Doença de Alzheimer , Nanopartículas de Magnetita , Nanotubos , Tronco Encefálico , Criança , Cidades , Trato Gastrointestinal , Humanos , México , Agregados Proteicos , Titânio/toxicidade , Adulto Jovem , alfa-Sinucleína
16.
Int J Nanomedicine ; 15: 6167-6182, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922000

RESUMO

Background: Among the novel cancer treatment strategies, combination therapy is a cornerstone of cancer therapy. Materials and Methods: Here, combination therapy with targeted polymer, magnetic hyperthermia and chemotherapy was presented as an effective therapeutic technique. The DOX-loaded PLA-PEG-FA magnetic nanoparticles (nanocarrier) were prepared via a double emulsion method. The nanocarriers were characterized by particle size, zeta potential, morphology, saturation magnetizations and heat generation capacity, and the encapsulation efficiency, drug content and in-vitro drug release for various weight ratios of PLA:DOX. Then, cytotoxicity, cellular uptake and apoptosis level of nanocarrier-treated cells for HeLa and CT26 cells were investigated by MTT assay, flow cytometry, and apoptosis detection kit. Results and Conclusions: The synthesized nanoparticles were spherical in shape, had low aggregation and considerable magnetic properties. Meanwhile, the drug content and encapsulation efficiency of nanoparticles can be achieved by varying the weight ratios of PLA:DOX. The saturation magnetizations of nanocarriers in the maximum applied magnetic field were 59/447 emu/g and 28/224 emu/g, respectively. Heat generation capacity of MNPs and nanocarriers were evaluated in the external AC magnetic field by a hyperthermia device. The highest temperature, 44.2°C, was measured in the nanocarriers suspension at w/w ratio 10:1 (polymer:DOX weight ratio) after exposed to the magnetic field for 60 minutes. The encapsulation efficiency improved with increasing polymer concentration, since the highest DOX encapsulation efficiency was related to the nanocarriers' suspension at w/w ratio 50:1 (79.6 ± 6.4%). However, the highest DOX loading efficiency was measured in the nanocarriers' suspension at w/w ratio 10:1 (5.14 ± 0.6%). The uptake efficiency and apoptosis level of nanocarrier-treated cells were higher than those of nanocarriers (folic acid free) and free DOX-treated cells in both cell lines. Therefore, this targeted nanocarrier may offer a promising nanosystem for cancer-combined chemotherapy and hyperthermia.


Assuntos
Doxorrubicina/farmacologia , Ácido Fólico/farmacologia , Hipertermia Induzida , Nanopartículas de Magnetita/química , Neoplasias/terapia , Polietilenoglicóis/química , Animais , Apoptose/efeitos dos fármacos , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Células HeLa , Humanos , Nanopartículas de Magnetita/ultraestrutura , Camundongos , Tamanho da Partícula , Polietilenoglicóis/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
17.
Sci Rep ; 10(1): 15447, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963318

RESUMO

In the paper, the results of the first regular studies of ultra-small iron oxide nanoparticles (IONPs) toxicity in vitro were presented. The influence of PEG-coated NPs with 5 nm magnetite core on six different cell lines was examined. These were: human bronchial fibroblasts, human embryonic kidney cells (HEK293T), two glioblastoma multiforme (GBM) cell lines as well as GBM cells isolated from a brain tumor of patient. Additionally, mouse macrophages were included in the study. The influence of IONPs in three different doses (1, 5 and 25 µg Fe/ml) on the viability, proliferation and migration activity of cells was assessed. Moreover, quantifying the intracellular ROS production, we determined the level of oxidative stress in cells exposed to IONPs. In the paper, for the first time, the effect of Fe in the form of IONPs was compared with the analogical data obtained for iron salts solutions containing the same amount of Fe, on the similar oxidation state. Our results clearly showed that the influence of iron on the living cells strongly depends not only on the used cell line, dose and exposure time but also on the form in which this element was administered to the culture. Notably, nanoparticles can stimulate the proliferation of some cell lines, including glioblastoma multiforme. Compared to Fe salts, they have a stronger negative impact on the viability of the cells tested. Ultra-small NPs, also, more often positively affect cell motility which seem to differ them from the NPs with larger core diameters.


Assuntos
Movimento Celular , Proliferação de Células , Compostos de Ferro/farmacologia , Nanopartículas de Magnetita/administração & dosagem , Teste de Materiais , Animais , Sobrevivência Celular , Células Cultivadas , Humanos , Técnicas In Vitro , Nanopartículas de Magnetita/química , Camundongos , Oxirredução , Tamanho da Partícula
18.
Ecotoxicol Environ Saf ; 206: 111336, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32977084

RESUMO

Widespread arsenic (As) contamination is a severe environmental and public health concern. Isatis cappadocica, an arsenic hyperaccumulator, holds great potential to clean up As-contaminated soil and groundwater. Iron oxide is one of the most common metal oxides in the natural environment and its nanoparticulate form has been previously utilized for the removal of heavy metals/metalloids from wastewater. However, there is a paucity of information on the impact of iron oxide nanoparticles on the growth and physiological properties of I. cappadocica and its effectiveness on As removal. Current study reports for the first time the impact of superparamagnetic iron oxide nanoparticles and glutathione (GSH) modified superparamagnetic iron oxide nanoparticles (nFe3O4 and nFe3O4@GSH) on the physiological characteristic of I. cappadocica and its accumulation of As under hydroponic condition. nFe3O4@GSH alleviated the harmful impact of As and significantly increased the shoot biomass of I. cappadocica by enhancing the plant defense mechanisms. The application of GSH, nFe3O4 and nFe3O4@GSH all lowered the As concentration in plant shoots as a protective mechanism. However, the substantial shoot biomass increase due to nFe3O4@GSH resulted in a 56% higher As accumulation in plant shoots than in plants exposed to As alone, indicating the strong effectiveness of nFe3O4@GSH as a novel enhancer of the As phytoremediation by I. cappadocica. Our data further showed that the beneficial effect of nFe3O4@GSH on As phytoremediation is due to the enhancement of activities of several enzymatic and nonenzymatic antioxidants.


Assuntos
Arsênico/metabolismo , Glutationa/metabolismo , Isatis/fisiologia , Poluentes do Solo/metabolismo , Antioxidantes , Arsênico/análise , Biodegradação Ambiental , Compostos Férricos , Hidroponia , Nanopartículas de Magnetita , Metais Pesados , Plantas
19.
Cancer Invest ; 38(8-9): 507-521, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32870068

RESUMO

Hyperthermic therapy is defined as increasing the temperature of tumor tissues to 40-43 °C that has been effective approach for destroying malignant cells in the field of cancer therapy. Recent line of research has applied different approaches along with hyperthermic treatment to obtain high efficiency and little side effects. Magnetic nanoparticle-based hyperthermia has demonstrated an improved functionality in targeting malignant cells and implement their therapeutic role by heating the tumor cells. Here in this review article, we clarify the diverse aspects of magnetic nanoparticles in the treatment of cancer.


Assuntos
Hipertermia Induzida/métodos , Nanopartículas de Magnetita/administração & dosagem , Neoplasias/terapia , Animais , Humanos , Fenômenos Magnéticos , Fototerapia/métodos
20.
PLoS One ; 15(9): e0238837, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32913353

RESUMO

The liquid foodstuffs such as edible oil products remain a problem of excessive aflatoxin B1 (AFB1) content. This paper focused on the preparation of magnetic mesoporous silica (MMS) from rice husk ash for the removal of AFB1 in oil system. The MMS preparation process, adsorption conditions, structural characteristics, and adsorption mechanism were investigated. The optimum conditions for MMS preparation were pH 11.0 and 80°C for 24 h. The characterization results showed that magnetic particles were successfully embedded in the MMS and had high responsiveness to a magnetic field, which was advantageous for recyclability. The MMS had ordered uniform channels with a specific surface area of 730.98 m2/g and pore diameter of 2.43 nm. The optimum adsorption conditions were 2 h at 20°C. For AFB1 with an initial concentration of 0.2 µg/mL, the MMS adsorption capacity was 171.98 µg/g and the adsorption rate was 94.59%. The MMS adsorption isotherm fitted the Langmuir model well under the assumption of monolayer AFB1 adsorption with uniformly distributed adsorption sites on the MMS surface. The maximum amount of AFB1 adsorbed according to the Langmuir isotherm was 1118.69 µg/g. A quasi-second-order kinetic model gave a better fit to the process of AFB1 adsorption on MMS. The values of ΔH (-19.17 kJ/mol) and ΔG (-34.09, -34.61, and -35.15 kJ/mol at 283, 293, and 303 K, respectively) were negative, indicating that AFB1 adsorption on MMS was a spontaneous exothermic process. The results indicated that MMS was a promising material for AFB1 removal in oil system, and this study will serve as a guide for practical MMS applications.


Assuntos
Aflatoxina B1/isolamento & purificação , Nanopartículas de Magnetita/química , Oryza/química , Dióxido de Silício/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/normas , Adsorção , Aflatoxina B1/análise , Concentração de Íons de Hidrogênio , Microesferas , Poluentes Químicos da Água/análise , Purificação da Água/métodos
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