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1.
Life Sci ; 271: 119070, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33465388

RESUMO

AIMS: In vivo biodistribution of radio labeled ZrO2 nanoparticles is addressed for better imaging, therapy and diagnosis. Nanoparticles are synthesized by microwave assisted sol-gel technique using Fe3O4 as a stabilizer. Antioxidant assay, hemolytic activity in human blood and biodistribution in rabbits was explored to study the therapeutical as well as in vivo targeted diagnostic applications of as synthesized nanoparticles. MAIN METHODS: Fe3O4 stabilized zirconia nanoparticles are synthesized using microwave assisted sol-gel method. Microwave (MW) powers are varied in the range of 100 to 1000 W. As synthesized nanoparticles are evaluated using different characterizations such as X-ray diffractometer, scanning electron microscope, Raman spectroscopy, impedance analyzer, Vickers micro hardness indenter, FTIR, and UV-Vis spectroscopy. In vitro activity of synthesized nanoparticles is checked in freshly extracted human blood serum. To study biodistribution of Fe3O4 stabilized zirconia nanoparticles in rabbit, technetium-99 m was used for labeling purpose. The labeling efficacy and stability of labeled nanoparticles are also measured with instant thin layer chromatography (ITLC) method. Intravenous injection of 99mTc-Fe3O4 stabilized zirconia nanoparticles (0.2 ml), containing 110 MBq of radioactivity, is performed to study the biodistribution; nanoparticles are injected into the ear vein of animal (rabbit). KEY FINDINGS: Zirconia (ZrO2) nanoparticles (NPs) are stabilized using Fe3O4 that were prepared by means of microwave assisted sol-gel method. Crystallite size (~20 nm) agrees well with the values required to stabilize tetragonal zirconia (t-ZrO2). Volume shrinkage results in high value of hardness (~1369). Dielectric constant values, compatible for biomedical application, are observed for tetragonally stabilized samples. Low value of hemolytic response is observed for Fe3O4 stabilized ZrO2 NPs. 99mTc radio labeled ZrO2 NPs proved to be potential candidate to study biodistribution. Biodistribution studies show stability of radiolabeled NPs in the original suspension as well as in blood serum. CT scan of rabbit is performed for several times to check the biodistribution of NPs with time and survival of rabbit. Results suggest that these NPs can also be used as targeted nanoparticles as well as variants of drug payload carrier. SIGNIFICANCE: Results signify that Fe3O4 stabilized ZrO2 nanoparticles synthesized by microwave assisted sol-gel method may be considered as "all-rounder" nanoplatform and are safe enough to be used in diagnostic as well as therapeutic purposes.


Assuntos
Compostos Férricos/metabolismo , Sequestradores de Radicais Livres/metabolismo , Micro-Ondas , Nanopartículas/metabolismo , Radioimunodetecção/métodos , Zircônio/metabolismo , Animais , Compostos Férricos/síntese química , Humanos , Nanopartículas/química , Coelhos , Tecnécio/metabolismo , Distribuição Tecidual/fisiologia , Difração de Raios X/métodos , Zircônio/química
2.
AAPS PharmSciTech ; 21(6): 235, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32803528

RESUMO

Development of a delivery system to lower systemic toxicity and enhance doxorubicin (DOX) antitumor efficacy against multi-drug resistant (MDR) tumors is of great clinical significance. Here, lipid/hyaluronic acid (HA)-coated DOX-Fe3O4 was characterized to determine its optimal safety and efficacy on a tumor. DOX was first conjugated onto the Fe3O4 NPs surface, which was subsequently coated with phosphatidylcholine (PC) lipids, which consisted of a tumor cell-targeting HA ligand, to generate a dual-targeting nanoparticle (NP). DOX-Fe3O4 synthesis was validated by the Fourier-transform infrared (FT-IR) analysis results. Core-shell PC/HA@DOX-Fe3O4 formation, which had an average particle size of 48.2 nm, was observed based on the transmission electron microscopy (TEM) and dynamic laser light scattering (DLS) results. The saturation magnetization value of PC/HA@DOX-Fe3O4 was discovered to be 28 emu/g using vibrating-sample magnetometry. Furthermore, the designed PC/HA@DOX-Fe3O4 achieved greater MCF-7/ADR cellular uptake and cytotoxicity as compared with DOX. In addition, PC/HA@DOX-Fe3O4 exhibited significant DOX tumor-targeting capabilities and enhanced tumor growth inhibition activity in the xenograft MCF-7/ADR tumor-bearing nude mice following magnetic attraction and ligand-mediated targeting, with less cardiotoxicity. Therefore, PC/HA@DOX-Fe3O4 is a potential candidate for MDR tumor chemotherapy. Graphical abstract.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Compostos Férricos/administração & dosagem , Ácido Hialurônico/administração & dosagem , Nanopartículas/administração & dosagem , Animais , Antibióticos Antineoplásicos/síntese química , Doxorrubicina/síntese química , Compostos Férricos/síntese química , Humanos , Ácido Hialurônico/síntese química , Lipídeos , Células MCF-7 , Camundongos , Camundongos Nus , Nanopartículas/química , Tamanho da Partícula , Distribuição Aleatória , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
3.
J Chromatogr A ; 1627: 461382, 2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823094

RESUMO

A method is described for the functionalization of magnetic carbon nanotubes to recognize aristolochic acid Ⅰ and Ⅱ. 3-Glycidyloxypropyltrimethoxysilane was used as a coupling agent to immobilize adenine on a solid support. The morphology and structure of adenine-coated magnetic carbon nanotubes was investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and a vibrating sample magnetometer (VSM). The adsorption performance of the adenine-coated magnetic carbon nanotubes was evaluated via adsorption isotherms, the kinetics and selectivity tests. The adsorption capacity of the adenine-functionalized sorbent for aristolochic acid Ⅰ was determined to be 24.5 µg mg-1. By combining magnetic solid phase extraction with HPLC detection, a method was developed to enrich and detect aristolochic acids used in traditional Chinese medicine. A satisfactory recovery (92.7 - 97.5% for aristolochic acid Ⅰ and 92.6 - 99.4% for aristolochic acid Ⅱ) and an acceptable relative standard deviation (<4.0%) were obtained.


Assuntos
Adenina/química , Ácidos Aristolóquicos/isolamento & purificação , Fenômenos Magnéticos , Nanotubos de Carbono/química , Adsorção , Medicamentos de Ervas Chinesas/química , Compostos Férricos/síntese química , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Cinética , Nanocompostos/química , Nanotubos de Carbono/ultraestrutura , Concentração Osmolar , Reprodutibilidade dos Testes , Dióxido de Silício/síntese química , Dióxido de Silício/química , Extração em Fase Sólida , Temperatura , Difração de Raios X
4.
Ecotoxicol Environ Saf ; 200: 110744, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32460050

RESUMO

Hematite nanoparticles (α-Fe2O3 NPs) were successfully synthesized by a low-cost solvent-free reaction using Ferrous sulfate waste (FeSO4·7H2O) and pyrite (FeS2) as raw materials and employed for the decolorization of Methyl Orange by the photo-Fenton system. The properties of α-Fe2O3 NPs before and after photo-Fenton reaction were characterized by X-ray powder diffraction (XRD), Field emission scanning electron microscopy (FESEM), Fourier transform infrared (FT-IR) spectrum and X-ray photoelectron spectroscopy (XPS), and the optical properties of α-Fe2O3 NPs were analyzed by UV-vis diffuse reflectance spectra (UV-vis DRS) and Photoluminescence (PL) spectra. The analytic results showed that the as-formed samples having an average diameter of ~50 nm exhibit pure phase hematite with sphere structure. Besides, little differences were found by comparing the characterization data of the particles before and after the photo-Fenton reaction, indicating that the photo-Fenton reaction was carried out in solution rather than on the surface of α-Fe2O3 NPs. A 24 central composite design (CCD) coupled with response surface methodology (RSM) was applied to evaluate and optimize the important variables. A significant quadratic model (P-value<0.0001, R2 = 0.9664) was derived using an analysis of variance (ANOVA), which was adequate to perform the process variables optimization. The optimal process conditions were performed to be 395 nm of the light wavelength, pH 3.0, 5 mmol/L H2O2 and 1 g/L α-Fe2O3, and the decolorization efficiency of methyl orange was 99.55% at 4 min.


Assuntos
Compostos Azo/química , Corantes/química , Compostos Férricos/química , Nanopartículas Metálicas/química , Catálise , Compostos Férricos/síntese química , Compostos Ferrosos/química , Ferro/química , Solventes , Sulfetos/química
5.
Int J Nanomedicine ; 15: 2583-2603, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368042

RESUMO

Introduction: Over the past several years, nano-based therapeutics were an effective cancer drug candidate in order to overcome the persistence of deadliest diseases and prevalence of multiple drug resistance (MDR). Methods: The main objective of our program was to design organosilane-modified Fe3O4/SiO2/APTS(~NH2) core magnetic nanocomposites with functionalized copper-Schiff base complex through the use of (3-aminopropyl)triethoxysilane linker as chemotherapeutics to cancer cells. The nanoparticles were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), TEM, and vibrating sample magnetometer (VSM) techniques. All analyses corroborated the successful synthesis of the nanoparticles. In the second step, all compounds of magnetic nanoparticles were validated as antitumor drugs through the conventional MTT assay against K562 (myelogenous leukemia cancer) and apoptosis study by Annexin V/PI and AO/EB. The molecular dynamic simulations of nanoparticles were further carried out; afterwards, the optimization was performed using MM+, semi-empirical (AM1) and Ab Initio (STO-3G), ForciteGemo Opt, Forcite Dynamics, Forcite Energy and CASTEP in Materials studio 2017. Results: The results showed that the anti-cancer activity was barely reduced after modifying the surface of the Fe3O4/SiO2/APTS nanoparticles with 2-hydroxy-3-methoxybenzaldehyde as Schiff base and then Cu(II) complex. The apoptosis study by Annexin V/PI and AO/EB stained cell nuclei was performed that apoptosis percentage of the nanoparticles increased upon increasing the thickness of Fe3O4 shell on the magnetite core. The docking studies of the synthesized compounds were conducted towards the DNA and Topoisomerase II via AutoDock 1.5.6 (The Scripps Research Institute, La Jolla, CA, USA). Conclusion: Results of biology activities and computational modeling demonstrate that nanoparticles were targeted drug delivery system in cancer treatment.


Assuntos
Cobre/química , Compostos Férricos/síntese química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Propilaminas/síntese química , Bases de Schiff/síntese química , Silanos/síntese química , Dióxido de Silício/síntese química , Apoptose , Núcleo Celular/metabolismo , DNA/química , DNA Topoisomerases Tipo II/química , Compostos Férricos/química , Humanos , Células K562 , Magnetismo , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Propilaminas/química , Bases de Schiff/química , Silanos/química , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
Int J Mol Sci ; 21(7)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32244817

RESUMO

Research on iron oxide-based magnetic nanoparticles and their clinical use has been, so far, mainly focused on the spherical shape. However, efforts have been made to develop synthetic routes that produce different anisotropic shapes not only in magnetite nanoparticles, but also in other ferrites, as their magnetic behavior and biological activity can be improved by controlling the shape. Ferrite nanoparticles show several properties that arise from finite-size and surface effects, like high magnetization and superparamagnetism, which make them interesting for use in nanomedicine. Herein, we show recent developments on the synthesis of anisotropic ferrite nanoparticles and the importance of shape-dependent properties for biomedical applications, such as magnetic drug delivery, magnetic hyperthermia and magnetic resonance imaging. A brief discussion on toxicity of iron oxide nanoparticles is also included.


Assuntos
Anisotropia , Compostos Férricos/química , Magnetismo , Nanopartículas de Magnetita/química , Sistemas de Liberação de Medicamentos/métodos , Compostos Férricos/síntese química , Humanos , Nanopartículas de Magnetita/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanomedicina/métodos
7.
Talanta ; 214: 120861, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32278413

RESUMO

A procedure for separation and preconcentration of tetracyclines from human serum samples involving magnetic dispersive micro-solid phase extraction was proposed. The extraction efficiency of different tetracyclines was improved with the use of the surfactant coated Fe3O4 magnetic nanoparticles. Sorption mechanism was presented, and the potential use of magnetic Fe3O4 nanoparticles coated with different surfactants for tetracyclines adsorption was demonstrated for the first time. The procedure involved nanoparticle floating in a liquid sample phase for analyte extraction followed by elution and determination by high performance liquid chromatography with diode array detection. Influence of the main involved parameters was studied, the system was dimensioned accordingly. The analytical curves were linear in the ranges of 0.25-10 mg L-1 for tetracycline and 0.10-10 mg L-1 for oxytetracycline or doxycycline. Limits of detection were estimated (IUPAC, 3 concept) as 0.08 mg L-1 for tetracycline, and 0.03 mg L-1 for oxytetracycline or doxycycline. The proposed procedure proved to be fast (10 min), simple (two stages), inexpensive (10 mg of nanoparticles) and was applied to human serum samples. Unlike previously synthesized nanoparticles for tetracyclines separation, the surfactant-coated Fe3O4 nanoparticles can be easily prepared with widely available and low-cost reagents. Moreover, elution of the analytes was accomplished in absence of organic solvents by an aqueous chelating agent solution.


Assuntos
Compostos Férricos/química , Nanopartículas de Magnetita/química , Microextração em Fase Sólida , Tensoativos/química , Tetraciclinas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Compostos Férricos/síntese química , Humanos , Fenômenos Magnéticos , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Tetraciclinas/sangue , Tetraciclinas/química
8.
Artigo em Inglês | MEDLINE | ID: mdl-32163004

RESUMO

This study aimed to synthesize Bi2Fe4O9 and apply it to the degradation of tartrazine yellow dye. Bi2Fe4O9 was synthesized using the solid-state reaction and the Pechini method. The materials obtained were characterized using X-ray diffraction (XRD), visible ultraviolet spectroscopy (UV-Vis) and field emission scanning electron microscopy (FEG). The microscopic images revealed a morphological difference between the two materials in which the material obtained by the Pechini method is the most porous and have the largest surface area. The pellet obtained by the Pechini method was seen to have a lower bandgap value when compared with the sample solid state reaction. In the photocatalysis tests, the best performance was also that of the material obtained by the Pechini method, with 99.34% degradation, while the material obtained by solid state reaction showed 85.86% in 120 minutes. The solution degraded with the material obtained by the Pechini method presented 81.66% of mineralization while the solution with the material obtained by solid state reaction showed 60.97% of mineralization. The results confirmed that the material obtained by both syntheses is able to maintain its effectiveness after 10 repetitions of the photocatalytic process, proving to be promising for waste treatment in the industrial field.


Assuntos
Bismuto/química , Corantes/análise , Compostos Férricos/química , Tartrazina/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Catálise , Compostos Férricos/síntese química , Microscopia Eletrônica de Varredura , Difração de Raios X
9.
Int J Mol Sci ; 21(1)2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31948078

RESUMO

In this work, we studied the anthracene oxidation by hydroxyl radicals. Hydroxyl radical was generated by reaction of 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin Fe (III) (TPPFe) with hydrogen peroxide under visible radiation at a nitrogen atmosphere. The TPPFe was synthesized by Adler Method followed by metal complexation with Fe (III) chloride hexahydrate. Hydroxyl radical was detected by fluorescence emission spectroscopy and we studied kinetic of anthracene selective oxidation by hydroxyl radicals through the differential method. The TPPFe was characterized by UV-Vis spectrophotometry, Dynamic Light Scattering (DLS) and Scanning Electron Microscopy (SEM) measurements. The results indicated that TPPFE was compound by micro-particles with a size distribution of around 2500 nm. Kinetic results showed that the apparent rate constant for the oxidation of anthracene increased exponentially on as temperature increases, furthermore, the activation energy for the Anthracene oxidation by hydroxyl radicals under visible irradiation was 51.3 kJ/mol. Finally, anthraquinone was the main byproduct generated after oxidation of anthracene by TPP-Fe under visible irradiation.


Assuntos
Antracenos/química , Radical Hidroxila/química , Antracenos/efeitos da radiação , Difusão Dinâmica da Luz , Compostos Férricos/síntese química , Compostos Férricos/química , Peróxido de Hidrogênio/química , Cinética , Luz , Microscopia Eletrônica de Varredura , Nitrogênio , Oxirredução , Porfirinas/síntese química , Porfirinas/química , Porfirinas/efeitos da radiação , Espectrometria de Fluorescência
10.
Environ Sci Pollut Res Int ; 27(9): 9181-9191, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31916149

RESUMO

Silica-based nanocomposite syntheses employ many harmful substances, which, in turn, demand the development of new synthetic environmental-friendly routes that meet the principles of green chemistry. In this work, we present a novel magnetic adsorbent, Fe2O3@SiO2 nanocomposite (Fe@SiNp), successfully obtained without surfactant, employing an electrochemical method. We characterized the nanocomposite and then applied it to remove aniline from the water medium. Characterization was carried out by vibrating-sample magnetometry (VSM), X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FT-IR). The parameters to the adsorptive removal of aniline were successfully optimized, which made possible to remove 71.04 ± 0.06% (126.6 ± 2.0 mg/g) from a 100 mg/L aniline solution at pH 6 and 323 K, by employing around 50 mg of Fe@SiNp, at a contact time of 40 min. The adsorption of aniline by Fe@SiNp is a spontaneous and exothermic process according to the pseudo-second-order kinetic model (r2 = 1 at 20 mg/L aniline concentration) and the Freundlich isotherm model (r2 = 0.9986).


Assuntos
Compostos Férricos/síntese química , Nanocompostos , Dióxido de Silício/síntese química , Poluentes Químicos da Água , Adsorção , Compostos de Anilina , Compostos Férricos/química , Cinética , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Top Curr Chem (Cham) ; 378(1): 12, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31907672

RESUMO

Nanomaterials have revolutionized the sensing and biosensing fields, with the development of more sensitive and selective devices for multiple applications. Gold, silver and iron oxide nanoparticles have played a particularly major role in this development. In this review, we provide a general overview of the synthesis and characteristics of gold, silver and iron oxide nanoparticles, along with the main strategies for their surface functionalization with ligands and biomolecules. Finally, different architectures suitable for electrochemical applications are reviewed, as well as their main fabrication procedures. We conclude with some considerations from the authors' perspective regarding the promising use of these materials and the challenges to be faced in the near future.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Compostos Férricos/síntese química , Ouro/química , Nanopartículas/química , Prata/química , Compostos Férricos/química , Ligantes , Propriedades de Superfície
12.
World J Microbiol Biotechnol ; 36(2): 25, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980951

RESUMO

In a search for novel therapeutic agents against pathogenic fungal species, Candida in addition to bacterial species, novel spinel nanoferrites were assayed against four pathogenic fungi isolated from different clinical samples of ear and skin infections: Aspergillus flavus, A. niger, A. terrus and A. fumigatus, four Candia species: Candida albicans, C. parapsilosis, C. krusei and C. tropicales, and four bacterial species: two Gram +ve: Bacillus subtilis and Streptococcus pyogenes, and two Gram -ve: Pseudomonas vulgaris and Escherichia coli. It was found that the assayed compounds displayed different levels of antifungal and antibacterial activities against all tested microorganisms. The antimicrobial potency depends on the method of synthesis of the nanoparticles and also on the microbial species.


Assuntos
Antibacterianos/síntese química , Antifúngicos/síntese química , Compostos Férricos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Compostos Férricos/química , Compostos Férricos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanopartículas , Relação Estrutura-Atividade
13.
Chemosphere ; 241: 125021, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31683448

RESUMO

The magnetic composite CoFe2O4/ZIF-8 based on metal organic framework (MOF) with high specific surface area and high activity was synthesized by solvothermal method. The prepared catalysts were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), vibration sample magnetometer (VSM) and N2 adsorption-desorption isotherms, respectively. After characterization, CoFe2O4/ZIF-8 was applied to heterogeneous activation of peroxymonosulfate (PMS) for degrading methylene blue (MB). The result showed that the 0.075-CoFe2O4/ZIF-8 sample had the excellent catalytic activity. After catalytic reaction for 60 min, the degradation efficiency of MB (20 mg/L) reached about 97.9% at room temperature of 20 °C. The quenching experiment and electron paramagnetic resonance (EPR) analysis indicated that SO4- and OH radicals were the main active species in MB degradation. Meanwhile, the possible MB degradation mechanism was proposed. After four catalytic cycles, the degradation efficiency of MB has not been greatly reduced, indicating the practical application potential of CoFe2O4/ZIF-8 in water pollution cleanup.


Assuntos
Cobalto/química , Corantes/química , Compostos Férricos/química , Estruturas Metalorgânicas/química , Peróxidos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Catálise , Compostos Férricos/síntese química , Magnetismo , Azul de Metileno/química
14.
Colloids Surf B Biointerfaces ; 186: 110717, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31864112

RESUMO

The effect of the ligand shell on the cellular uptake efficiency was evaluated by a systematic study using fully dispersed 6 nm diameter superparamagnetic iron oxide nanoparticles (SPIONs), mono and bis-conjugated with glycerol phosphate (glyc), dopamine (dopa), 4,5-dihydroxy-1,3-benzenedisulfonic acid (tiron) and phosphorylethanolamine (pea). Negatively charged SPION-glyc was more efficiently incorporated than positively charged SPION-pea and SPION-dopa clearly evidencing that there are strong enough short-range interactions in addition to the long-range electrostatic interactions, as measured by the zeta potential, to reverse our expectation on cellular uptake. Those effects were pursued by correlating the nanoparticles incorporation efficiency as a function of the respective zeta potentials and the molar fractions of glyc and pea ligands co-conjugated on the SPION surface. The possibility of associating different ligands to modulate the physicochemical properties and biological events was demonstrated, showing promising perspectives for the development of multifunctional nanosystems for biomedical applications.


Assuntos
Compostos Férricos/farmacocinética , Nanopartículas de Magnetita/química , Compostos Férricos/síntese química , Compostos Férricos/química , Células HeLa , Humanos , Hidrodinâmica , Ligantes , Tamanho da Partícula , Eletricidade Estática , Propriedades de Superfície , Distribuição Tecidual , Células Tumorais Cultivadas
15.
IET Nanobiotechnol ; 13(7): 697-702, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31573538

RESUMO

The toxicity of arsenic in drinking water is hazardous for human health. Different strategies are used for arsenic removal from drinking water. Nanoparticles with higher adsorption capacities are useful for arsenic remediation. In the current study, magnesium ferrite nanoparticles were synthesised by three different methods followed by their characterisation XRD, SEM, and EDX. The SEM morphology and the porosity of magnesium ferrite nanoparticles were best in case of auto-combustion method. These particles had an average particle size of about 20-50 nm with spherical shape. These particles showed efficient remediation of arsenic up to 96% within 0.5 h. However, the co-precipitation and sol-gel-based nanoparticles showed arsenic remediation upto85 and 87% at 0.5-h time point. Moreover, the minimum inhibitory concentration of nanoparticles against two strains E.coli and Pseudomonas aeruginosa was found to be4.0 mg/L of these nanoparticles. However, the sol-gel-based nanoparticles showed efficient anti-microbial activity against E.coli at 4.0 and 8.0 mg/L against Pseudomonas aeruginosa. The co-precipitation-based nanoparticles were least efficient both for arsenic remediation and anti-microbial purposes. Thus, the synthesised auto-combustion-based nanoparticles are multifunctional in nature.


Assuntos
Anti-Infecciosos/síntese química , Compostos Férricos/síntese química , Compostos de Magnésio/síntese química , Nanopartículas/química , Nanotecnologia/métodos , Purificação da Água , Adsorção , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Arsênio/isolamento & purificação , Arsênio/farmacocinética , Recuperação e Remediação Ambiental/métodos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Compostos Férricos/química , Compostos Férricos/farmacocinética , Humanos , Compostos de Magnésio/química , Compostos de Magnésio/farmacocinética , Teste de Materiais , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/farmacocinética , Purificação da Água/instrumentação , Purificação da Água/métodos , Difração de Raios X
16.
Langmuir ; 35(45): 14465-14472, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31612722

RESUMO

Catechols are prone to oxidative polymerization as well as complex formation with metal ions. These two features of catechols have played an important role in the construction of functional films on various surfaces. For example, marine antifouling films and antibacterial films were successfully prepared by oxidative polymerization and metal complexation of catechol-containing molecules, respectively. However, the effect of simultaneous metal complexation and oxidative polymerization on functional film formation has not yet been fully investigated. Herein, as a derivative of 3-(3,4-dihydroxyphenyl)-l-alanine (DOPA), we synthesized an ethylene glycol-derivatized DOPA (OEG-DOPA) and formed OEG-DOPA thin films based on (1) oxidative polymerization and (2) the complexation between catechol groups of OEG-DOPA and iron(III) (FeIII) ions. Either or both approaches were used for the film formation. OEG-DOPA film formation was characterized by ellipsometry, contact angle goniometry, field emission scanning electron microscopy, and X-ray photoelectron spectroscopy. Among the conditions used, the formation of a uniform film was only achieved with the dual cross-linking system of FeIII complexation and oxidation-induced covalent bond formation. Compared to the uncoated substrate and other OEG-DOPA films prepared under different conditions, the uniform OEG-DOPA film strongly inhibited bacterial adhesion, showing excellent antibacterial capability. We think that our surface-coating strategy can be applied to medical devices, tools, and implants where bacterial adhesion and biofilm formation should be prevented. This work can also serve as a basis for the construction of functional thin films for other catechol-functionalized materials.


Assuntos
Antibacterianos/síntese química , Etilenoglicol/química , Compostos Férricos/síntese química , Levodopa/química , Antibacterianos/química , Compostos Férricos/química , Estrutura Molecular , Oxirredução , Tamanho da Partícula , Propriedades de Superfície
17.
Mater Sci Eng C Mater Biol Appl ; 104: 109932, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499934

RESUMO

Nanomaterial based paints are in current demand in the area of surface protective coatings due to the significant advances made to improve their antibacterial and anticorrosion characteristics. In this work, we have developed magnetic graphene oxide (MGO) paint with the incorporation of cobalt ferrite (CF) and graphene oxide (GO) along with paint materials by using high energy ball milling (HEBM). Morphological, elemental and functional analysis of the MGO paint is studied with ESEM, AFM, Raman, FTIR spectroscopy. EDS and PIXE methods are used for elemental analysis. Thermal analysis shows that the MGO film was stable up to 100 °C. The saturation magnetization of CF MNP is observed as 76 emu/g and it is reduced to 12 emu/g for MGP paint. The detailed antibacterial study of the prepared MGO paint has performed with S. typhimurium and E. coli. The dead-live assessment shows the dead population for S. typhimurium is superior up to 82% whereas it is 20% for E. coli. The morphological damage of bacterial cells is studied using SEM technique. Flow cytometry analysis of reactive oxygen species (ROS) generation experiments and computational analysis supported the proposed mechanism of induced ROS for the damage of bacterial membrane via interaction of GO and CF with bacterial proteins leading to alteration in their functionality. The observed results indicate that the prepared MGO paint could be a better candidate in the area of nano paint for surface protective coatings.


Assuntos
Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/síntese química , Compostos Férricos/síntese química , Grafite/síntese química , Nanopartículas de Magnetita/química , Via Secretória/efeitos dos fármacos , Antibacterianos/síntese química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Materiais Revestidos Biocompatíveis/farmacologia , Cobalto/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Compostos Férricos/farmacologia , Grafite/farmacologia , Humanos , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento , Salmonella typhimurium/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Propriedades de Superfície , Temperatura , Termogravimetria , Vibração
18.
Mater Sci Eng C Mater Biol Appl ; 104: 109922, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499936

RESUMO

Synthesis of monodisperse carboxylic acid-functionalized magnetic mesoporous silica nanoparticles is performed by either two-step sol-gel process or post-grafting using citric acid modified isocyanate silane coupling agent (MMSN-NCO-CA) or succinic anhydride modified magnetic mesoporous silica (MMSN-NH-SA). Morphology, structure and magnetic properties of bare and mesoporous silica coated Fe3O4 core were studied using various techniques such as FTIR, VSM, TEM, FESEM, XRD and N2 adsorption-desorption isotherms (BET). Cisplatin (cis-Pt) adsorption isotherms and its release profile in various media were investigated by ICP-OES. MMSN-NCO-CA with mean particle size 107 nm had lower surface area (87.5 m2/g) and larger pore size (6.9 nm) in comparison with MMSN-NH-SA (respective values of 151.2 m2/g and 3.5 nm). cis-Pt loading into particles followed a saturable adsorption with respect to the drug to particle mass ratios. More sustained release of cis-Pt was observed for MMSN-NCO-CA, though both nanoparticles exhibited a pH- and saline concentration-dependent drug release. In addition, general and cis-Pt specific cytotoxicity were examined by MTT assay in MDA-MB-231 breast cancer cell line, and to further detect apoptosis, acridine orange/ethidium bromide dual cell staining was investigated by fluorescence microscopy. In-vitro anti-tumor efficiency of cis-Pt loaded MMSN-NCO-CA and MMSN-NH-SA were similarly enhanced in comparison to free cis-Pt; however, more specific apoptotic death occurred for cis-Pt loaded MMSN-NCO-CA. Therefore, the as-synthesized citric acid functionalized core-shell magnetic mesoporous hybrid nanoparticles could be used as a promising drug carriers for cancer therapy in-vivo.


Assuntos
Cisplatino/administração & dosagem , Ácido Cítrico/química , Sistemas de Liberação de Medicamentos , Compostos Férricos/química , Nanopartículas/química , Salinidade , Silanos/química , Dióxido de Silício/química , Adsorção , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ácido Cítrico/síntese química , Liberação Controlada de Fármacos , Compostos Férricos/síntese química , Hemólise , Humanos , Hidrodinâmica , Concentração de Íons de Hidrogênio , Cinética , Magnetometria , Nanopartículas/ultraestrutura , Porosidade , Silanos/síntese química , Dióxido de Silício/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Propriedades de Superfície , Difração de Raios X
19.
Molecules ; 24(14)2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31319493

RESUMO

CuO/MgAl2O4 and CuO/MgFe2O4 catalysts were successfully synthesized with the use of spinel supports by a very simple and low-cost mechanochemical method. High-speed ball-milling was used to synthesize these catalyst supports for the first time. Materials were subsequently characterized by using XRD, FESEM, TEM, EDS-Dot mapping, XPS, BET-BJH, and Magnetic Susceptibility to investigate the physical-chemical characteristics of the catalysts. Acidity evaluation results indicated that the catalyst with the Mg-Al spinel support had more acid sites. XRD results showed a successful synthesis of the catalysts with large crystal sizes. Both catalysts were used in isoeugenol oxidation and vanillyl alcohol to vanillin reactions, with the CuO/MgAl2O4 showing optimum results. This catalyst provided 67% conversion (74% selectivity) after 2 h and this value improved to 81% (selectivity 100%) with the second reaction after 8 h. The CuO/MgFe2O4 catalyst in the first reaction after five hours revealed 53% conversion (47% selectivity) and after eight hours with the second reaction, the conversion value improved to 64% (100% selectivity). In terms of reusability, CuO/MgAl2O4 showed better results than the CuO/MgFe2O4 catalyst, for both reactions.


Assuntos
Óxido de Alumínio/química , Benzaldeídos/síntese química , Compostos Férricos/química , Compostos de Magnésio/química , Óxido de Magnésio/química , Óxido de Alumínio/síntese química , Benzaldeídos/química , Álcoois Benzílicos/química , Catálise , Cobre/química , Eugenol/análogos & derivados , Eugenol/química , Compostos Férricos/síntese química , Compostos de Magnésio/síntese química , Óxido de Magnésio/síntese química , Oxirredução
20.
Molecules ; 24(14)2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31319597

RESUMO

MnFe2O4 NPs are successfully decorated on the surface of SiO2 sheets to form the SiO2-MnFe2O4 composite via one-pot hydrothermal synthesis method. The phase identification, morphology, crystal structure, distribution of elements, and microwave absorbing properties in S-band (1.55~3.4 GHz) of the as-prepared composite were investigated by XRD, SEM, TEM, and Vector Network Analyzer (VNA) respectively. Compared with the pure MnFe2O4 NPs, the as-prepared SiO2-MnFe2O4 composite exhibits enhanced microwave absorption performance in this frequency band due to the strong eddy current loss, better impedance matching, excellent attenuation characteristic, and multiple Debye relaxation processes. The maximum reflection loss of -14.87 dB at 2.25 GHz with a broader -10 dB bandwidth over the frequency range of 1.67~2.9 GHz (1.23 GHz) can be obtained at the thickness of 4 mm. Most importantly, the preparation method used here is relatively simple, hence such composite can be served as a potential candidate for effective microwave absorption in S-band.


Assuntos
Compostos Férricos/síntese química , Compostos de Manganês/síntese química , Micro-Ondas , Dióxido de Silício/síntese química , Compostos Férricos/química , Magnetismo , Compostos de Manganês/química , Estrutura Molecular , Dióxido de Silício/química , Difração de Raios X
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