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1.
ACS Appl Mater Interfaces ; 13(40): 47784-47792, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34585581

RESUMO

Indium gallium zinc oxide (IGZO) is one of the most promising materials for diverse optoelectronic applications based on thin-film transistors (TFTs) including ultraviolet (UV) photodetectors. In particular, the monitoring of UV-A (320-400 nm) exposure is very useful for healthcare applications because it can be used to prevent various human skin and eye-related diseases. However, the relatively weak optical absorption in the UV-A range and the persistent photoconductivity (PPC) arising from the oxygen vacancy-related states of IGZO thin films limit efficient UV monitoring. In this paper, we report the enhancement of the UV photoresponse characteristics of IGZO photo-TFTs by the surface functionalization of biomolecules on an IGZO channel. The biomaterial/IGZO interface plays a crucial role in enhancing UV-A absorption and suppressing PPC under negative gate bias, resulting in not only increased photoresponsivity and specific detectivity but also a fast and repeatable UV photoresponse. In addition, turning off the device without external bias completely eliminates PPC due to the internal electric field induced by the surface functionalization of biomaterials. Such a volatile feature of PPC enables the fast and repeatable UV photoresponse. These results suggest the potential of IGZO photo-TFTs combined with biomaterials for real-time UV monitoring.


Assuntos
Óxidos/química , Transistores Eletrônicos , Raios Ultravioleta , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Gálio/química , Gálio/efeitos da radiação , Índio/química , Índio/efeitos da radiação , Proteínas Luminescentes/química , Proteínas Luminescentes/efeitos da radiação , Óxidos/efeitos da radiação , Compostos de Zinco/química , Compostos de Zinco/efeitos da radiação
2.
ACS Appl Mater Interfaces ; 13(24): 28650-28661, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34124895

RESUMO

Novel and effective radiosensitizers that can enhance radiosensitivity of tumor tissues and increase the local radiation dose are highly desirable. In this work, templated by bovine serum albumin (BSA), Bi2Se3-MnO2 nanocomposites (Bi2Se3-MnO2@BSA) were fabricated via biomineralization, while Bi2Se3 nanodots act as radiosensitizers to increase the local radiation dosage because of their strong X-ray attenuation ability, and MnO2 with catalase-like activity can increase the oxygen concentration in tumors by triggering the decomposition of tumor endogenous H2O2 so as to improve the hypoxia-associated radioresistance of tumors. Owing to the interaction of the two components in the interface, Bi2Se3-MnO2@BSA showed promoted catalytic activity compared to MnO2@BSA, favoring tumor radiotherapy (RT) sensitization. BSA templating enabled the nanocomposites with high colloidal stability and biocompatibility as well as satisfactory tumor targeting both in vitro and in vivo; thus, an enhanced RT efficacy was obtained. Moreover, the proposed Bi2Se3-MnO2@BSA exhibited excellent performances in computerized tomography and magnetic resonance imaging. Thus, this work provides a tumor microenvironment-responsive multifunctional theranostic nanoagent with an improved performance for imaging-guided tumor RT sensitization.


Assuntos
Antineoplásicos/uso terapêutico , Bismuto/uso terapêutico , Compostos de Manganês/uso terapêutico , Nanocompostos/uso terapêutico , Neoplasias/tratamento farmacológico , Óxidos/uso terapêutico , Radiossensibilizantes/uso terapêutico , Compostos de Selênio/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/efeitos da radiação , Bismuto/química , Catálise/efeitos da radiação , Bovinos , Linhagem Celular Tumoral , Meios de Contraste/síntese química , Meios de Contraste/efeitos da radiação , Meios de Contraste/uso terapêutico , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Compostos de Manganês/química , Compostos de Manganês/efeitos da radiação , Camundongos Endogâmicos BALB C , Nanocompostos/química , Nanocompostos/efeitos da radiação , Neoplasias/diagnóstico por imagem , Óxidos/química , Óxidos/efeitos da radiação , Oxigênio/metabolismo , Medicina de Precisão , Radiossensibilizantes/síntese química , Radiossensibilizantes/efeitos da radiação , Compostos de Selênio/química , Compostos de Selênio/efeitos da radiação
3.
ACS Appl Mater Interfaces ; 13(26): 31066-31076, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34137247

RESUMO

The serious problem of pharmaceutical and personal care product pollution places great pressure on aquatic environments and human health. Herein, a novel coating photocatalyst was synthesized by adhering Ag-AgCl/WO3/g-C3N4 (AWC) nanoparticles on a polydopamine (PDA)-modified melamine sponge (MS) through a facile layer-by-layer assembly method to degrade trimethoprim (TMP). The formed PDA coating was used for the anchoring of nanoparticles, photothermal conversion, and hydrophilic modification. TMP (99.9%; 4 mg/L) was removed in 90 min by the photocatalyst coating (AWC/PDA/MS) under visible light via a synergistic photocatalytic-photothermal performance route. The stability and reusability of the AWC/PDA/MS have been proved by cyclic experiments, in which the removal efficiency of TMP was still more than 90% after five consecutive cycles with a very little mass loss. Quantitative structure-activity relationship analysis revealed that the ecotoxicities of the generated intermediates were lower than those of TMP. Furthermore, the solution matrix effects on the photocatalytic removal efficiency were investigated, and the results revealed that the AWC/PDA/MS still maintained excellent photocatalytic degradation efficiency in several actual water and simulated water matrices. This work develops recyclable photocatalysts for the potential application in the field of water remediation.


Assuntos
Nanopartículas/química , Trimetoprima/química , Catálise/efeitos dos fármacos , Grafite/química , Grafite/efeitos da radiação , Indóis/química , Indóis/efeitos da radiação , Luz , Nanopartículas/efeitos da radiação , Compostos de Nitrogênio/química , Compostos de Nitrogênio/efeitos da radiação , Óxidos/química , Óxidos/efeitos da radiação , Polímeros/química , Polímeros/efeitos da radiação , Prata/química , Prata/efeitos da radiação , Compostos de Prata/química , Compostos de Prata/efeitos da radiação , Temperatura , Triazinas/química , Triazinas/efeitos da radiação , Tungstênio/química , Tungstênio/efeitos da radiação , Purificação da Água/métodos
4.
Chemosphere ; 262: 128082, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182100

RESUMO

As important natural oxidants and adsorbents, manganese (Mn) oxide minerals affect the speciation, bioavailability and fate of pollutants and nutrient elements. It was found that birnessite-type Mn(IV) oxide minerals can be formed in the presence of NO3- and solar irradiation. However, the photochemical formation and transformation processes from Mn2+ to Mn(IV) oxide minerals remain unclear. In this work, the Mn(IV) oxide minerals were confirmed to be photochemically formed mainly due to the disproportionation of Mn(III) intermediates generated from the oxidation of Mn2+ in the presence of NO3- under UV light irradiation. The oxidation rate of Mn2+ to Mn(IV) oxide minerals decreased with increasing initial Mn2+ concentration due to the lower disproportionation rate. The increase in NO3- concentration, pH and temperature promoted Mn2+ photochemical oxidation. The photochemical formation rate of Mn(IV) oxide minerals increased with increasing ligand concentrations at low ligand concentrations. Ligands affected the formation of Mn(IV) oxide minerals by promoting the formation and reducing the reactivity of Mn(III) intermediates. Overall, this work reveals the important role of Mn(III) intermediates in the formation of natural Mn oxide minerals.


Assuntos
Compostos de Manganês/química , Manganês/química , Minerais/química , Óxidos/química , Luz Solar , Manganês/efeitos da radiação , Compostos de Manganês/efeitos da radiação , Minerais/efeitos da radiação , Modelos Teóricos , Oxirredução , Óxidos/efeitos da radiação , Processos Fotoquímicos , Temperatura
5.
J Mater Chem B ; 8(36): 8356-8367, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32794542

RESUMO

The integration of advanced diagnostic contrast agents with versatile therapeutic drugs is an effective method for cancer treatment. However, combining various biocompatible theranostic modalities into a single platform at the nanoscale is a challenging assignment. In this work, we report a simple chemical synthetic route for producing a homogeneous hybrid nanoflower shaped morphology based on Au@Mn3O4 magneto-plasmonic nanomaterials. The synthetic mechanism of the nanoflowers is well-matched with the heteroepitaxial growth phenomena by which the nano-petals of Mn3O4 generated on the surface of the Au core. The food and drug administration (FDA) in the USA approved the use of triblock polymer Pluronic F-127 to enhance the biocompatibility of Au@Mn3O4 hybrid nanoflowers. The prepared hybrid nanoflowers produce a significant photothermal heating effect with a thermal transduction efficiency of 38%, comparable to the nanorods and nanoparticles of gold (Au). The hybrid junction reveals promising optical and magnetic properties and the prepared Au@Mn3O4 nanoflowers not only exhibit strong near-infrared (NIR) absorption to produce excellent photothermal efficacy under irradiation with an 808 nm NIR laser, but also demonstrate a significant T1-weighted magnetic resonance (MR) image enhancement in vitro and in vivo. The histopathology assessments indicate only negligible toxicity of the nanoflowers to major organs. Therefore, the hybrid Au@Mn3O4 nanoflowers exhibit great potential in T1-weighted MR-imaging and photothermal therapy, opening up new possibilities for synthesizing novel bio-compatible, homogeneous, and shape controllable nanostructures with multifunctional applications.


Assuntos
Meios de Contraste/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Meios de Contraste/síntese química , Meios de Contraste/efeitos da radiação , Feminino , Ouro/química , Ouro/efeitos da radiação , Ouro/uso terapêutico , Raios Infravermelhos , Imageamento por Ressonância Magnética/métodos , Compostos de Manganês/química , Compostos de Manganês/efeitos da radiação , Compostos de Manganês/uso terapêutico , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Camundongos Nus , Óxidos/química , Óxidos/efeitos da radiação , Óxidos/uso terapêutico , Terapia Fototérmica/métodos , Nanomedicina Teranóstica
6.
Anal Chim Acta ; 1125: 299-307, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32674777

RESUMO

As a broad-spectrum tetracycline antibiotic, the overuse of oxytetracycline (OTC) causes antibiotics residues in the environment and seriously threats to human health owing to effective antibacterial properties. Thus, it is particularly important to design a photoelectrochemical (PEC) aptasensor to detect OTC with excellent performance. Herein, we developed a selective and stable PEC aptasensor of OTC on the basis of Co3O4 nanoparticles (Co3O4 NPs)/graphitic carbon nitride (g-CN) heterojunction, used as PEC active materials. The Co3O4 NPs were successfully grown on the g-CN via grinding and calcining mixture of Co3O4 precursors and bulk g-CN. The Co3O4/g-CN heterojunction with improved light utilization and promoted electrons/holes separation capability can exhibit higher PEC signal than that of g-CN. In order to implement the purpose of specific recognition, OTC-aptamer was introduced into modified electrode to construct highly selective PEC aptasensor for OTC determination, which can possess wide linear range (0.01-500 nM) with low detection limit (3.5 pM, S/N = 3). This PEC aptasensor platform with excellent selectivity and high stability can provide a practical application in the field of water monitoring.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Nanopartículas Metálicas/química , Oxitetraciclina/análise , Fotoquímica/métodos , Sequência de Bases , Cobalto/química , Cobalto/efeitos da radiação , Grafite/química , Grafite/efeitos da radiação , Luz , Limite de Detecção , Nanopartículas Metálicas/efeitos da radiação , Compostos de Nitrogênio/química , Compostos de Nitrogênio/efeitos da radiação , Óxidos/química , Óxidos/efeitos da radiação , Oxitetraciclina/química , Reprodutibilidade dos Testes , Rios/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
7.
ACS Appl Mater Interfaces ; 12(17): 19357-19368, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32275133

RESUMO

Local surface plasmon resonance (LSPR)-enhanced catalysis has brought a substantial amount of opportunities across various disciplines such as photocatalysis, photodetection, and photothermal therapeutics. Plasmon-induced photothermal and hot carriers effects have also been utilized to activate the enzyme-like reactions. Compared with natural enzymes, the relatively low catalytic performance of nanozymes severely hampered the potential applications in the field of biomedicine. For these issues mentioned above, herein, we demonstrate a highly efficient sulfite oxidase (SuOx) mimetic performance of plasmonic monolayer MoOx (ML-MoOx) upon LSPR excitation. We also established that the considerable photothermal effect and the injection of hot carriers induced by LSPR are responsible for promoting the SuOx activity of ML-MoOx. The high transient local temperature on the surface of ML-MoOx generated by the photothermal effect facilitates to impact the reaction velocity and feed the SuOx-like activity, while the generation of hot carriers which are suggested as predominant effects catalyzes the oxidation of sulfite to sulfate through significantly decreasing the activation energy for the SuOx-like reaction. These investigations present a contribution to the basic understanding of plasmon-enhanced enzyme-like reaction and provided an insight into the optimization of the SuOx mimetic performance of nanomaterials.


Assuntos
Molibdênio/química , Óxidos/química , Sulfitos/química , Catálise/efeitos da radiação , Temperatura Alta , Raios Infravermelhos , Cinética , Modelos Químicos , Molibdênio/efeitos da radiação , Oxirredução , Óxidos/síntese química , Óxidos/efeitos da radiação , Sulfatos/síntese química , Sulfito Oxidase/química , Ressonância de Plasmônio de Superfície
8.
J Hazard Mater ; 393: 122366, 2020 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-32120212

RESUMO

Thin 2D/2D WO3/g-C3N4 Step-scheme (S-scheme) heterojunction with carbon doping and bridge (C-W/N) was constructed with anionic polyacrylamide (APAM), in which APAM functioned as an assistant templet and a carbon source. APAM and WO3 were inserted into g-C3N4 nanosheet. The carbon, thin planar structure and WO3 with oxygen vacancies result in fast charge transfer, high quantum efficiency and strong driving force for photocatalytic reaction. Consequently, as-prepared C-W/N ternary composite photocatalyst exhibited significantly enhanced photocatalytic performance for tetracycline (TC) degradation under visible light compared to pure g-C3N4, WO3 and other binary composites. Moreover, the material showed high stability and reusability in cyclic TC degradation. The principal intermediate products over C-W/N photocatalyst were revealed by HPLC-MS analysis. Corresponding degradation pathway of TC was also presented in this work. According to the trapping experiments, analysis of electron spin resource (ESR) and band gap, possible charge transfer pathways of C-W/N are proposed and discussed in detail. Based on the results, carbon derived from APAM works not only as electron mediator but also as acceptor for photocatalytic degradation reaction. It is a promising way to further modulate heterojunction for varies applications.


Assuntos
Resinas Acrílicas/química , Grafite/química , Compostos de Nitrogênio/química , Óxidos/química , Tetraciclina/química , Tungstênio/química , Catálise/efeitos da radiação , Poluentes Ambientais/química , Grafite/efeitos da radiação , Luz , Compostos de Nitrogênio/efeitos da radiação , Óxidos/efeitos da radiação , Tungstênio/efeitos da radiação
9.
J Hazard Mater ; 390: 122158, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32004762

RESUMO

In this study, MoS2/ZnSnO3 (MS-ZSO) composite photocatalyst with loading MS nanosheets onto the surface of porous ZSO microcubes was synthesized using a simple hydrothermal route. The prepared MS-ZSO composite can be easily excited under visible light, and 3 % MS-ZSO exhibits an outstanding photo-degradation (>80 % in 60 min) and mineralization performance (>42 % in 60 min) of the tetracycline. A remarkable improvement in the photocatalytic activity of MS-ZSO composite derived from a positive synergistic effect of well-matched energy level positions, increasement the absorption of visible light, prolonged life time decay and improved interfacial charge transfer between MS and ZSO. In-depth investigation on charge carrier separation mechanism toward MS/ZSO composite under visible light was proposed, which was further evidenced by capture experiments and electron spin resonance (ESR) techniques. Furthermore, the corresponding intermediates of tetracycline degradation over MS-ZSO composites were inspected by liquid chromatography-mass spectrometry (LC-MS) analysis, and the possible degradation paths were proposed.


Assuntos
Antibacterianos/química , Dissulfetos/efeitos da radiação , Luz , Molibdênio/efeitos da radiação , Nanoestruturas/efeitos da radiação , Óxidos/efeitos da radiação , Tetraciclina/química , Compostos de Estanho/efeitos da radiação , Compostos de Zinco/efeitos da radiação , Catálise , Dissulfetos/química , Molibdênio/química , Nanoestruturas/química , Óxidos/química , Processos Fotoquímicos , Compostos de Estanho/química , Compostos de Zinco/química
10.
J Hazard Mater ; 390: 122050, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32007859

RESUMO

In this paper, in-situ fabrication of tungsten oxide (WO3) on carbon nano-tube (CNT) was performed via sol-gel/hydrothermal method to prepare WO3/CNT nanocomposites and then coupled with visible light and ultrasound (US) irradiations for sono-photocatalytic removal of tetracycline (TTC) and pharmaceutical wastewater treatment. The as-prepared catalysts were characterized by FT-IR, XRD, TEM, UV-VIS DRS, FESEM, EDS, TGA, BET, BJH, EIS, and EDX techniques. The characterization tests, indicated successful incorporation of CTNs into the WO3 framework and efficient reduction of charge carries recombination rate after modifying with CNT. The investigation of experimental parameters verified that 60 mg/L TTC could be perfectly degraded at optimum operational parameters (WO3/CNT: 0.7 g/L, pH: 9.0, US power: 250 W/m2, and light intensity: 120 W/m2 over 60 min treatment. Trapping experiments results verified that HO radicals and h+ were the main oxidative species in degradation of TTC. The as-prepared photocatalysts could be reused after six successive cycles with an approximately 8.8 % reduction in removal efficiency. Investigation of the effect of real pharmaceutical wastewater revealed that this system is able to eliminate 83.7 and 90.6 % of TOC and COD, respectively after 220 min of reaction time. Some compounds with lower toxic impact and molecular weight, compared to raw pharmaceutical wastewater, were detected after treatment by sono-photocatalysis process. The biodegradability of real pharmaceutical wastewater was improved significantly after treatment by WO3/CNT sono-photocatalysis.


Assuntos
Antibacterianos/química , Luz , Nanotubos de Carbono/efeitos da radiação , Óxidos/efeitos da radiação , Tetraciclina/química , Tungstênio/efeitos da radiação , Ondas Ultrassônicas , Poluentes Químicos da Água/química , Catálise , Indústria Farmacêutica , Resíduos Industriais , Nanocompostos/química , Nanocompostos/efeitos da radiação , Nanotubos de Carbono/química , Óxidos/química , Processos Fotoquímicos , Tungstênio/química , Águas Residuárias , Purificação da Água/métodos
12.
Sci Rep ; 9(1): 9927, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31289314

RESUMO

The ability to manipulate the structure and function of promising systems via external stimuli is emerging with the development of reconfigurable and programmable multifunctional materials. Increasing antifungal and antitumor activity requires novel, effective treatments to be diligently sought. In this work, the synthesis, characterization, and in vitro biological screening of pure α-Ag2WO4, irradiated with electrons and with non-focused and focused femtosecond laser beams are reported. We demonstrate, for the first time, that Ag nanoparticles/α-Ag2WO4 composite displays potent antifungal and antitumor activity. This composite had an extreme low inhibition concentration against Candida albicans, cause the modulation of α-Ag2WO4 perform the fungicidal activity more efficient. For tumor activity, it was found that the composite showed a high selectivity against the cancer cells (MB49), thus depleting the populations of cancer cells by necrosis and apoptosis, without the healthy cells (BALB/3T3) being affected.


Assuntos
Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Candida albicans/efeitos dos fármacos , Elétrons , Nanopartículas Metálicas/química , Óxidos/química , Prata/química , Tungstênio/química , Neoplasias da Bexiga Urinária/tratamento farmacológico , Animais , Apoptose , Células 3T3 BALB , Proliferação de Células , Humanos , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/efeitos da radiação , Camundongos , Óxidos/efeitos da radiação , Prata/efeitos da radiação , Células Tumorais Cultivadas , Tungstênio/efeitos da radiação , Neoplasias da Bexiga Urinária/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
13.
J Hazard Mater ; 377: 227-236, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31170571

RESUMO

Herein, a heterostructure based on MnO2 and g-C3N4 was constructed on the surface of metallic Ti implants, in which MnO2 favored the transfer and separation of free charges to enhance the photoconversion efficiency of g-C3N4 by 21.11%. Consequently, the yield of ROS was promoted significantly, which denatured protein and damaged DNA to kill bacteria efficiently. In addition, glutathione (GSH, l-γ-glutamyl-l-cysteinyl-glycine) defending oxidative stress in bacteria, was oxidized by MnO2 in the hybrid coating once the bacterial membrane was disrupted by ROS. Hence, after visible light irradiation for 20 min, MnO2/g-C3N4 coating exhibited superior disinfection efficacy of 99.96% and 99.26% against S. aureus and E. coli severally. This work provided a practical sterilization strategy about MnO2/g-C3N4 systems through the synergistic effects of enhanced photodynamic antibacterial therapy and oxidization effect of MnO2 with great biosafety, in which MnO2 enhanced the photocatalyst property of g-C3N4 to generate more ROS and deplete GSH to improve antibacterial efficiency. It will bring more insight into rapid and highly effective disinfection and antibacterial strategy without using traditional high-temperature, ultraviolet ray and antibiotics that cause side-effects.


Assuntos
Grafite/química , Compostos de Manganês/química , Compostos de Nitrogênio/química , Óxidos/química , Processos Fotoquímicos , Esterilização/métodos , Bactérias/metabolismo , Bactérias/efeitos da radiação , Catálise , Membrana Celular/metabolismo , Membrana Celular/efeitos da radiação , Dano ao DNA , Escherichia coli/efeitos da radiação , Glutationa/metabolismo , Grafite/efeitos da radiação , Luz , Compostos de Manganês/efeitos da radiação , Testes de Sensibilidade Microbiana , Modelos Moleculares , Compostos de Nitrogênio/efeitos da radiação , Óxidos/efeitos da radiação , Espécies Reativas de Oxigênio , Staphylococcus aureus/metabolismo , Staphylococcus aureus/efeitos da radiação
14.
J Hazard Mater ; 375: 161-173, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31055193

RESUMO

A novel Z-scheme system, Ag/ZnFe2O4/Ag/BiTa1-xVxO4 with enhanced electron transfer capacity was constructed for degrading sulfanilamide (SAM) using solar light. The photocatalytic activity of Ag/ZnFe2O4/Ag/BiTa1-xVxO4 was investigated. The effects of the mass ratio (ZnFe2O4:BiTaO4), doped V dose, Ag wt.% content, and irradiation time on the catalytic performance were evaluated. The reasonable mechanism of Ag/ZnFe2O4/Ag/BiTa1-xVxO4 solar photocatalytic degradation was also presented. These results reveal Ag/ZnFe2O4/Ag/BiTa1-xVxO4 possesses enhanced photocatalytic performance. The loaded Ag as electron mediator increases the electron transfer rate. Particularly, the doped V and the Fe ions from ZnFe2O4 form a powerful electron driving force, which enhances the electron transfer capacity. Ag/ZnFe2O4/Ag/BiTa1-xVxO4 shows optimal photocatalytic performance at 2.0 wt.% Ag and 0.5% doped V dose (ZnFe2O4:BiTaO4 = 1.0:0.5). Also, Ag/ZnFe2O4/Ag/BiTa1-xVxO4 exhibits high stability and repeatability in photocatalytic degradation. Several active species (•OH, •O2-, and h+) are produced in the Z-scheme photodegradation of SAM. These results on the enhanced photocatalytic activity of Ag/ZnFe2O4/Ag/BiTa1-xVxO4 are ascribed to synergistic photocatalytic effects of ZnFe2O4 and BiTa1-xVxO4 mediated through Ag and driven by doped V and Fe ions. Therefore, the Z-scheme Ag/ZnFe2O4/Ag/BiTa1-xVxO4 photocatalytic technology proves to be promising for the solar photocatalytic treatment of antibiotics under solar light.


Assuntos
Antibacterianos/química , Compostos Férricos , Metais Pesados , Nanocompostos , Óxidos , Sulfanilamida/química , Compostos de Zinco , Catálise , Compostos Férricos/química , Compostos Férricos/efeitos da radiação , Metais Pesados/química , Metais Pesados/efeitos da radiação , Nanocompostos/química , Nanocompostos/efeitos da radiação , Oxirredução , Óxidos/química , Óxidos/efeitos da radiação , Fotólise , Luz Solar , Compostos de Zinco/química , Compostos de Zinco/efeitos da radiação
15.
J Environ Sci (China) ; 79: 161-173, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30784441

RESUMO

Although manganese oxides are known for their semiconductor characteristics, the photocatalytic performance of conducting polymer intercalated K-Birnessite (K-Bi) has not been explored till date. With the view to design a visible light driven organic-inorganic hybrid photocatalyst for rapid degradation of Bisphenol A (BPA), the present work reports the ultrasound-assisted green synthesis of K-Bi/polypyrrole (Ppy) nanohybrids. The loading of Ppy in K-Bi was confirmed by thermogravimetric analysis while the formation of organic-inorganic hybrid was confirmed by infrared spectroscopy. K-Bi revealed a band gap of 2.8 eV while for the nanohybrids it was found to be ranging between 2.4 and 1.6 eV. X-ray diffraction studies confirmed partial intercalation of Ppy chains in the inter-layer space of K-Bi. High resolution transmission electron microscopy and scanning electron microscopy studies showed mixed morphology of K-Birnessite/Ppy nanohybrids. Rapid degradation of BPA was observed under visible irradiation in presence of K-Bi/Ppy nanohybrids and almost 90% degradation of 20 mg/L BPA solution was achieved within 120 min. The degradation was found to follow pseudo-first order kinetics and the degraded fragments were identified using liquid chromatography-mass spectrometry. Degradation pathway was proposed based on density-functional theory calculations of fukui index predicting the radical easy-attacking (f0) and (f-) sites in BPA.


Assuntos
Compostos Benzidrílicos/química , Disruptores Endócrinos/química , Nanoestruturas/efeitos da radiação , Óxidos/efeitos da radiação , Fenóis/química , Polímeros/efeitos da radiação , Pirróis/efeitos da radiação , Poluentes Químicos da Água/química , Catálise , Luz , Nanoestruturas/química , Óxidos/química , Fotólise , Polímeros/química , Pirróis/química , Ondas Ultrassônicas , Eliminação de Resíduos Líquidos
16.
Radiat Prot Dosimetry ; 186(1): 88-93, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30649472

RESUMO

In this work, we report some preliminary results regarding the analysis of electron spin resonance (ESR) response of soda-lime samples used for retrospective dosimetry. Six different soda-lime glass batches were evaluated after irradiation. We compared several dose reconstruction techniques: saturation method, subtraction method and g-effective, geff, approach. The differences were observed and discussed. ESR signal responses of soda-lime glass samples to different radiation doses for the triage application were investigated. Results confirmed that geff approach has potential for the identification and dosimetry of irradiated soda-lime glass samples using either additive dose method or only calibration curve.


Assuntos
Compostos de Cálcio/efeitos da radiação , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Espectroscopia de Ressonância de Spin Eletrônica/estatística & dados numéricos , Vidro/efeitos da radiação , Óxidos/efeitos da radiação , Radiometria/métodos , Hidróxido de Sódio/efeitos da radiação , Triagem/métodos , Compostos de Cálcio/química , Relação Dose-Resposta à Radiação , Raios gama , Vidro/química , Humanos , Óxidos/química , Hidróxido de Sódio/química
17.
Int J Pharm ; 557: 66-73, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30580088

RESUMO

Graphene oxide (GO) owns huge surface area and high drug loading capacity for aromatic molecules, such as doxorubicin (DOX). However, its biocompatibility is poor and it might agglomerate in physiological conditions. Chemical modification of GO with hydrophilicpolymer, especially PEGylation, was a common method to improve its biocompatibility. But the chemical modification of GO was complicated, and its drug loading capacity might be reduced because of the occupation of its functional groups. In this study, DOX-PEG polymers with different PEG molecular weights were synthesized to modify nano graphene oxide (NGO) to simultaneously realize the solubilization of NGO and the high loading capacity of DOX. The result showed that the drug release of NGO@DOX-PEG was pH sensitive. NIR irradiation could augment the drug release, cellular uptake, cytotoxicity and nuclear translocation of nanodrugs. Among the three kinds of nanodrugs, NGO@DOX-PEG5K was superior to others. It suggested that after conjugating with PEG, the bond between DOX-PEG and NGO was weakened, which resulted in a better drug release and treatment effect. In summary, the NIR and pH dual-responsive NGO@DOX-PEG nanodrugs were developed by noncovalent modification, and it demonstrated excellent biocompatibility and photochemical therapeutic effect, presenting a promising candidate for antitumor therapy, especially NGO@DOX-PEG5K.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos/administração & dosagem , Grafite/administração & dosagem , Nanopartículas/administração & dosagem , Óxidos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Doxorrubicina/química , Doxorrubicina/efeitos da radiação , Portadores de Fármacos/química , Portadores de Fármacos/efeitos da radiação , Liberação Controlada de Fármacos , Grafite/química , Grafite/efeitos da radiação , Células HeLa , Humanos , Luz , Nanopartículas/química , Nanopartículas/efeitos da radiação , Óxidos/química , Óxidos/efeitos da radiação , Fotoquimioterapia , Polietilenoglicóis/química , Polietilenoglicóis/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Solubilidade
18.
Analyst ; 143(20): 4967-4973, 2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30225468

RESUMO

A multifunctional nanosystem, which integrates biosensing, bioimaging, and therapeutic functions into a single nanoprobe, is of great significance for biosensing and biomedicine. Near-infrared (NIR) graphene quantum dots (GQDs) have emerged as an attractive bioimaging and therapy tool for exploring biological events because they can provide deep imaging penetration and low fluorescence background and produce 1O2 for PDT. Here, we reported a GQD-based multifunctional two-photon nanoprobe for intracellular tumor-related glutathione (GSH) detection and enhanced photodynamic therapy by reducing GSH levels in cancer cells. By taking the excellent quenching property of MnO2 nanosheets and the reduction ability of GSH, a GQD@MnO2 nanoprobe was developed through adsorption of MnO2 nanosheets onto the surface of GQDs for sensing intracellular tumor-related GSH. The nanoprobe shows a highly sensitive response to GSH in aqueous solutions with a detection limit of 83 nM. It also exhibits a high selectivity toward GSH relative to other biomolecules and electrolytes. In addition, once endocytosed, the MnO2 nanosheets are reduced by intracellular GSH, simultaneously releasing GQDs and decreasing the level of GSH for highly efficient PDT.


Assuntos
Glutationa/análise , Glutationa/metabolismo , Grafite/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Pontos Quânticos/química , Animais , Fluorescência , Grafite/química , Grafite/efeitos da radiação , Grafite/toxicidade , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Compostos de Manganês/efeitos da radiação , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Óxidos/química , Óxidos/farmacologia , Óxidos/efeitos da radiação , Óxidos/toxicidade , Fótons , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Fármacos Fotossensibilizantes/toxicidade , Pontos Quânticos/efeitos da radiação , Pontos Quânticos/toxicidade , Ratos
19.
J Hazard Mater ; 360: 481-489, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30144767

RESUMO

Photocatalytic ozonation has great potential in wastewater treatment. However, the role of ozone and the contribution of photogenerated hole in this process have not been fully understood. Here three WO3 materials are synthesized and used as model catalysts in visible-light photocatalytic ozonation for the mineralization of pharmaceutical pollutants. A dual role of ozone in this process has been confirmed: (i) direct oxidation of the pollutant till formation of refractory intermediates, (ii) efficient trapping of photoelectron that cannot be captured by O2. The latter is crucial because it not only induces the O3--mediated pathway for hydroxyl radical (OH) formation but also separates the hole which has proven to be capable of oxidizing water into OH. Evidenced by photoluminescence results, the intrinsic charge separation ability of WO3 in photocatalytic ozonation is no more as important as that in photocatalysis with O2. Finally, this process is more applicable under acidic condition. This work contributes to a better understanding of the significance of ozone in WO3 photocatalytic ozonation and provides us an insight into the mechanism of photocatalytic ozonation.


Assuntos
Oxidantes/química , Óxidos/química , Ozônio/química , Preparações Farmacêuticas/química , Tungstênio/química , Poluentes Químicos da Água/química , Catálise , Luz , Óxidos/efeitos da radiação , Fotólise , Tungstênio/efeitos da radiação , Purificação da Água/métodos
20.
Ecotoxicol Environ Saf ; 163: 620-628, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30096663

RESUMO

Nanosized BaFe1-xCuxO3 powders were prepared using the Pechini method. To limit grain growth and agglomeration, the temperature of calcination was limited to 800 °C. For all samples, the cubic form of BaFeO2.75 was predominant with minor additional phases. Cu doping was found to have a remarkable effect on the structural cubic unit cell parameter as the Cu concentration increased. As shown by XRD,the samples were in the nanometer size range (17-63 nm). However, as the Cu concentration increases, the agglomeration increases with the highest surface area for the BaFe0.95Cu0.05O3 composition, which also displays the highest photocatalytic atrazine degradation. For this sample, more than 90% degradation of atrazine was obtained at the optimum conditions (120 min irradiation under visible light at pH 11 using 0.75 mg of the catalyst). The Atrazine degradation was found to follow the pseudo-order kinetics. GC/MS was used to detect the intermediates and the reaction pathways. All the prepared samples and produced waters at the end of the experiment were found to be nontoxic.


Assuntos
Atrazina/efeitos da radiação , Herbicidas/efeitos da radiação , Luz , Óxidos/química , Atrazina/química , Catálise , Herbicidas/química , Cinética , Óxidos/efeitos da radiação , Fotólise , Temperatura
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