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1.
Sci Rep ; 13(1): 4742, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36959203

RESUMO

Ag3PO4/Ag4P2O7 photocatalysts were successfully synthesized by microwave-hydrothermal method. Tuning the properties of photocatalysts was achieved using different amount of acetic acid (CH3COOH) and sodium hydroxide (NaOH) to adjust pH value of precursor solution (pH = 4, 7, 10 and 12). The crystal structure, morphology and optical property of samples were characterized and explained. The photocatalytic activity of sample was determined by degradation of rhodamine B (RhB) and methyl orange (MO) under a wavelength range of 350-700 nm irradiation. The results demonstrated that the change in shape of particles was not observed whereas the average particle size was decreased with increasing pH value because of the high hydroxide ions (OH-). The sample synthesized in the solution with the pH of 10 exhibited excellent photocatalytic performance and stability because of the highest surface area and the present of Ag4P2O7 on the surface of particles. The highest photodegradation efficiency was 99.34 and 96.12% by degrading RhB and MO, respectively. The enhancement of photocatalytic performance of Ag3PO4/Ag4P2O7 was discussed. The active species trapping experiments showed that the h+ was the main active species to decompose the dye molecules.

2.
Talanta ; 225: 122009, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592748

RESUMO

Visible-light activated photocatalytic coatings may represent an attractive antimicrobial solution in domains such as food, beverage, pharmaceutical, biomedical and wastewater remediation. However, testing methods to determine the antibacterial effects of photocatalytic coatings are limited and require specialist expertise. This paper describes the development of a method that enables rapid screening of coatings for photocatalytic-antibacterial activity. Relying on the ability of viable microorganisms to reduce the dye resazurin from a blue to a pink colour, the method relates the time taken to detect this colour change with number of viable microorganisms. The antibacterial activity of two photocatalytic materials (bismuth oxide and titanium dioxide) were screened against two pathogenic organisms (Escherichia coli and Klebsiella pneumoniae) that represent potential target microorganisms using traditional testing and enumeration techniques (BS ISO 27447:2009) and the novel rapid method. Bismuth oxide showed excellent antibacterial activity under ambient visible light against E. coli, but was less effective against K. pneumoniae. The rapid method showed excellent agreement with existing tests in terms of number of viable cells recovered. Due to advantages such as low cost, high throughput, and less reliance on microbiological expertise, this method is recommended for researchers seeking an inexpensive first-stage screen for putative photocatalytic-antibacterial coatings.


Assuntos
Escherichia coli , Titânio , Antibacterianos/farmacologia , Catálise , Luz , Titânio/farmacologia
3.
Cell Biochem Biophys ; 79(1): 133-139, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33064258

RESUMO

Herein, we studied the effect of labile iron (ferric chloride) on the progression of liver cancer cells (HepG2.2.15). The iron was found to induce cell proliferation, growth, and migration in both traditional two-dimensional (2D) and three-dimensional cell (3D) culture models. Biophysical and cell cycle determinations also showed the change in functional cellular biophysical features (cell morphology) and cell cycle kinetic during cancer cell growth induced by the labile iron. According to immunofluorescence and the iron uptake inhibition studies, L-type calcium channel was found to plays a role in the iron uptake in the liver cancer cells. This report gives new insights into iron-mediated cancer cell growth and will pave the new way to diagnosis and treatment of liver cancer.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Ferro/metabolismo , Neoplasias Hepáticas/metabolismo , Transporte Biológico , Biofísica , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio , Ciclo Celular , Proliferação de Células , Cloretos , Progressão da Doença , Compostos Férricos , Células Hep G2 , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Cinética , Metástase Neoplásica , Transdução de Sinais , Sais de Tetrazólio/química , Tiazóis/química
4.
Nanoscale Res Lett ; 12(1): 589, 2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29124448

RESUMO

Stibnite (Sb2S3) semiconducting material was successfully synthesized by a rapid and facile microwave route using antimony chloride (SbCl3) and sodiumthiosulfate (Na2S2O3) dissolved in propylene glycol (PG) containing different hydroxyethyl cellulose (HEC) masses. The phase identification, morphology, and elemental composition of products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field- emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The results revealed the orthorhombic phase of Sb2S3 single crystal-forming sheaf-like nanostructure, and a possible formation mechanism was proposed and discussed. Its direct band gap calculated from UV-visible absorption is 1.60 eV. In this research, the photocatalytic activities of Sb2S3 nanostructure were investigated through the degradation of methyl orange (MO) and methylene blue (MB) under visible light irradiation. The as-obtained 0.30 g HEC-added solution (0.3 HEC-Sb2S3) photocatalyst exhibited better photocatalytic activity than the other products, which degraded 91% of MO within 300 min and 90% of MB within 240 min under the Xe-lamp irradiation. The first-order plot was fitted with this experiment which the rate constant (k) of 0.3 HEC-Sb2S3 for MO and MB degradation are 0.0085 and 0.0098 min-1, respectively. Therefore, the new experience with a novel and simple synthetic procedure of Sb2S3 photocatalyst that exhibits the characteristics of a highly effective photocatalyst under visible light irradiation was discovered.

5.
Biointerphases ; 12(2): 021005, 2017 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-28592112

RESUMO

Herein, a new magnetic resonance imaging (MRI) agent based on molecular nanoparticles of iron(III)-tannic complexes (Fe-TA NPs) is reported. The paramagnetic and molecularlike Fe-TA NPs were successfully synthesized at room temperature within a few minutes without the use of any toxic agents or expensive equipment. The coordination states of the Fe-TA NPs were pH-dependent. The r1 relaxivity values of the bis-dominated and tris-dominated structures of the Fe-TA NPs were determined to be 6.31 and 5.24 mM-1 s-1, respectively, by using a Philips Achieva 1.5T MRI scanner. The Fe-TA NPs were 177 ± 12 nm in diameter (hydrodynamic size) with a zeta potential value of -28 ± 0.9 mV, dispersing very well in aqueous solution and were highly stable in phosphate buffered saline buffer (pH 7.4) containing competitive ligands and metals. From in vitro studies, it was evident that the Fe-TA NPs exhibited good biocompatibility, with high cellular uptake in HepG2 cells. Clearly, the Fe-TA NPs were found to induce signal enhancement in the T1-weighted image of the HepG2 cells. As a result, it can be stated that the Fe-TA NPs may have the potential for being developed as low-cost and clinically translatable magnetic resonance imaging agents in the near future.


Assuntos
Meios de Contraste , Complexos de Coordenação , Ferro , Imageamento por Ressonância Magnética/métodos , Nanopartículas , Taninos , Meios de Contraste/química , Meios de Contraste/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Células Hep G2 , Humanos , Ferro/química , Ferro/farmacologia , Teste de Materiais/métodos , Nanopartículas/química , Nanopartículas/uso terapêutico , Taninos/química , Taninos/farmacologia
6.
Int J Pharm ; 524(1-2): 30-40, 2017 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-28359812

RESUMO

Herein, a new nanodrug that exhibits multi-therapeutic modalities for synergistic treatment of hepatocellular carcinoma is reported. The nanodrug is composed of carboxymethyl cellulose modified silver indium sulfide nanoparticle (CMC-AgInS2 NP, served as a source of reactive oxygen species) covalently linked with deferoxamine (DFO, served as iron chelating agent). The DFO/CMC-AgInS2 nanodrug was taken up by the HepG2 cell and accumulated within the cytosol as well as the nucleus, leading to induction of cell arrest in the G2/M phase and subsequent apoptosis cell death. Compared to DFO, the DFO/CMC-AgInS2 nanodrug demonstrated better anti-proliferative activity against the HepG2 cell. As they were cultured in a medium supplemented with ferric ions, the HepG2 cells were induced to grow faster as compared to the cells without the addition of ferric ions. Fortunately, our nanodrug was found to inhibit the cell growth induced by ferric ions. Our results indicate that the nanodrug has synergistic effect for treatment of HepG2 cells via the intrinsic therapeutic property of CMC-AgInS2 NP and the iron chelating capability of DFO.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Desferroxamina/farmacologia , Quelantes de Ferro/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Nanopartículas Metálicas/química , Células Hep G2 , Humanos
7.
Int J Pharm ; 473(1-2): 469-74, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25089503

RESUMO

We report herein the development of a smart magnetic nanoparticle-aptamer probe, or theranostic nanoprobe, which can be used for targeted imaging and as a drug carrier for hepatocellular carcinoma treatment. The theranostic nanoprobe combines the delivery potential of a non-toxic cellulose derivative polymer, specific capability of cancer-specific molecule (DNA-based EpCAM aptamer) and the imaging capability of magnetic iron oxide nanoparticles. Our proof-of-concept design demonstrates efficient in vitro MR imaging of the cancer cells, and enhanced delivery of an anticancer drug into the cancer cells with comparable treatment efficacy.


Assuntos
Antígenos de Neoplasias/genética , Antimetabólitos Antineoplásicos/administração & dosagem , Aptâmeros de Nucleotídeos/administração & dosagem , Carboximetilcelulose Sódica/administração & dosagem , Moléculas de Adesão Celular/genética , Doxorrubicina/administração & dosagem , Compostos Férricos/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Antimetabólitos Antineoplásicos/química , Aptâmeros de Nucleotídeos/química , Carboximetilcelulose Sódica/química , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Molécula de Adesão da Célula Epitelial , Compostos Férricos/química , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Fenômenos Magnéticos , Imageamento por Ressonância Magnética , Nanopartículas Metálicas/química
8.
Colloids Surf B Biointerfaces ; 113: 249-53, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24103503

RESUMO

Carboxymethyl modified magnetic nanoparticles (CMC-MNPs) have been designed as a vehicle for drug delivery in both drug-sensitive and drug-resistant cancer cells. We have demonstrated that the CMC-MNPs were able to load doxorubicin (DOX) with a high loading efficiency while also maintaining a good colloidal stability in an aqueous solution. According to a drug release study, DOX-loaded CMC-MNPs showed that the pH-dependent drug release property had a much higher release rate in acidic pH. Compared to free DOX, the DOX-loaded CMC-MNPs showed higher DOX accumulation in drug-sensitive cancer cells and much higher accumulation in drug-resistant cancer cells. These results indicate that our nanoplatform is highly efficient as a drug delivery system in both normal cancer cells and MDR cancer cells. In addition, the DOX-loaded CMC-MNPs can also enhance cytotoxicity against drug-resistant cancer cells in comparison to free DOX. The results obtained in this research demonstrate that our nanoplatform may be a promising approach in cancer chemotherapy and for overcoming multidrug-resistant cancer cells.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/farmacologia , Nanopartículas de Magnetita/química , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Resistencia a Medicamentos Antineoplásicos , Humanos
9.
J Nanosci Nanotechnol ; 13(3): 2189-92, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23755664

RESUMO

Oleic acid (OA) capped Bi2S3 quantum dots were successfully synthesized using 180 watt microwave power for 5 minutes in water-ethanol mixed solvents containing oleic acid as capping agent. In this approach, the reaction was conducted in ambient air and a much lower temperature than hot injection approach. The OA capped Bi2S3 QDs were characterized by using XRD, TEM, FTIR, UV-Vis and PL. The OA capped Bi2S3 QDs can be readily modified with sodium dodecyl sulfate (SDS) via hydrophobic interaction to improve their solubility in aqueous solution. According to optical properties of the QDs, the modified QD revealed the additional features, such as photothermal therapeutic agent and fluorescent probe.


Assuntos
Micro-Ondas , Pontos Quânticos , Sulfetos/síntese química , Bismuto , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
10.
J Nanosci Nanotechnol ; 10(4): 2853-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20355513

RESUMO

PbS with nano- and micro-crystals was hydrothermally synthesized from Pb(NO3)2 and thiosemicarbazide using carboxymethyl cellulose (CMC) as a template at 140, 180 and 200 degrees C for 12 h. CMC, NaOH and hydrothermal temperatures have the influence on the product morphologies characterized using a scanning electron microscope (SEM) and a transmission electron microscope (TEM). PbS (cubic) composing of Pb and S was detected using an X-ray diffractometer (XRD), a selected area electron diffraction (SAED) technique and an energy dispersive X-ray (EDX) analyzer. The interpreted patterns are in accordance with those of the simulations. Raman spectrometer revealed the presence of the vibration modes at 136, 278, 432, 602 and 967 cm(-1). Emission spectra of the products were detected at 384-388 nm using a photoluminescence (PL) spectrometer.

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