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1.
Artigo em Inglês | MEDLINE | ID: mdl-31484371

RESUMO

A novel graphite-phase carbon nitride (g-C3N4)/bismuth ferrite (BiFeO3)/carbon nanotubes (CNTs) ternary magnetic composite (CNBT) was prepared by a hydrothermal synthesis. Using this material, Cr(VI) and methylene blue (MB) were removed from wastewater through synergistic adsorption and photocatalysis. The effects of pH, time, and pollutant concentration on the photocatalytic performance of CNBT, as well as possible interactions between Cr(VI) and MB species were analyzed. The obtained results showed that CNTs could effectively reduce the recombination rate of electron-hole pairs during the photocatalytic reaction of the g-C3N4/BiFeO3 composite, thereby improving its photocatalytic performance, while the presence of MB increased the reduction rate of Cr(VI). After 5 h of the simultaneous adsorption and photocatalysis by CNBT, the removal rates of Cr(VI) and MB were 93% and 98%, respectively. This study provides a new theoretical basis and technical guidance for the combined application of photocatalysis and adsorption in the treatment of wastewaters containing mixed pollutants.


Assuntos
Bismuto/química , Cromo/química , Compostos Férricos/química , Grafite/química , Azul de Metileno/química , Nanocompostos/química , Nanotubos de Carbono/química , Compostos de Nitrogênio/química , Raios Ultravioleta , Poluentes Químicos da Água/química , Adsorção , Catálise , Compostos Férricos/efeitos da radiação , Grafite/efeitos da radiação , Nanocompostos/efeitos da radiação , Nanotubos de Carbono/efeitos da radiação , Compostos de Nitrogênio/efeitos da radiação , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Poluentes Químicos da Água/efeitos da radiação
2.
Analyst ; 144(19): 5717-5723, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31482883

RESUMO

An innovative visible light-driven photoelectrochemical (PEC) immunosensing system was reasonably established for the sensitive detection of prostate-specific antigen (PSA) by using perovskite metal oxide@gold nanoparticle heterostructures (BaTiO3/Au) as the photoactive materials. When plasmonic Au nanoparticles were directly decorated on BaTiO3, a several times surface plasmon resonance (SPR) enhancement of photocurrent density was induced via the injection of hot electrons from visible light-excited Au nanoparticles into the conduction band of BaTiO3, and the combination of BaTiO3 and Au nanoparticles was employed as a promising platform for developing a photoelectrochemical bioanalysis. As a proof of concept, PSA had been detected by the BaTiO3/Au nanocomposite-based PEC sensor. To design such an immunoassay protocol, a monoclonal anti-PSA capture antibody (cAb)-coated microplate and glucose oxidase/polyclonal anti-PSA detection antibody-modified gold nanoparticles (GOx-Au NP-dAb) were used as the immunoreaction platform and signal probe, respectively. Upon the addition of target PSA, a sandwiched immunocomplex was formed accompanying the immuno-recognition between the antigen and antibody, and then the carried GOx could oxidize glucose to produce H2O2. The photocurrent of the BaTiO3/Au nanocomposite-functionalized electrode amplified with increasing H2O2 concentration since H2O2 is considered as a good hole scavenger. On the basis of the above-mentioned mechanisms and the optimized conditions, the assembled PEC immunosensor was linear with the logarithm of the PSA concentration in the range of 0.01-40 ng mL-1 with a detection limit of 4.2 pg mL-1. It afforded rapid response, good precision, and high stability and specificity, implying its great promise in photoelectrochemical immunoassays. More generally, this system sets up an ideal PEC immunosensing system based on the BaTiO3/Au nanocomposites and represents an innovative and low-cost "signal-on" assay scheme for the practical quantitative screening of low-abundance proteins.


Assuntos
Compostos de Bário/química , Ouro/química , Calicreínas/sangue , Nanopartículas Metálicas/química , Antígeno Prostático Específico/sangue , Titânio/química , Anticorpos Monoclonais/imunologia , Compostos de Bário/efeitos da radiação , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Glucose/análise , Glucose Oxidase/química , Ouro/efeitos da radiação , Humanos , Peróxido de Hidrogênio/química , Imunoensaio/métodos , Calicreínas/imunologia , Luz , Limite de Detecção , Nanopartículas Metálicas/efeitos da radiação , Nanocompostos/química , Nanocompostos/efeitos da radiação , Processos Fotoquímicos , Estudo de Prova de Conceito , Antígeno Prostático Específico/imunologia , Ressonância de Plasmônio de Superfície/métodos , Titânio/efeitos da radiação
3.
Nanotechnology ; 30(49): 495501, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31443101

RESUMO

With the capability of inducing small particle sizes of supported metal in graphite oxide (GO), the γ-ray irradiation method applied for preparing graphite oxide-gold (GO-Au) nanocomposites as electrochemical immunosensors has attracted specific attention recently. To study the accurate factors influencing the precise morphology and final performance of the prepared composites in the γ-irradiation system, we proposed a facile method to investigate the evolution of the GO structure, size and dispersion of Au nanoparticles (AuNPs) produced with the addition of isopropyl alcohol to the system. The GO-Au nanocomposites were characterized by Fourier transform infrared spectroscopy, x-ray diffraction spectra, Raman spectra, x-ray photoelectron spectroscopy and high resolution transmission electron microscopy. These nanocomposites with sandwich morphology exhibited an excellent immunosensor performance with a low detection limit of 15.8 pg ml-1 (S/N = 3) and a wide linear range from 1 to 40 ng ml-1 for detecting carcinoembryonic antigens. The enhanced biosensing performance is attributed to the synergistic effect of γ-irradiation and the precise structure of GO, which endows the smaller size and more uniform distribution of AuNPs on the GO as well as the good signal amplification capability. Furthermore, adopting the γ-irradiation method and use of GO as a precursor is propitious for application in large-scale production because of its high-efficiency and high-yielding characteristics.


Assuntos
Técnicas Biossensoriais , Antígeno Carcinoembrionário/sangue , Ouro/química , Imunoensaio , Nanopartículas Metálicas/química , Nanocompostos/química , 2-Propanol/química , Anticorpos Imobilizados/química , Técnicas Eletroquímicas , Raios gama , Grafite/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/efeitos da radiação , Nanopartículas Metálicas/ultraestrutura , Nanocompostos/efeitos da radiação , Nanocompostos/ultraestrutura , Óxidos/química
4.
Anal Chim Acta ; 1077: 281-287, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31307720

RESUMO

Herein, a novel signal-off photoelectrochemical (PEC) aptasensor was proposed for sensitive detection of thrombin on the basis of C60@C3N4 nanocomposites as quencher and Au nanoparticles (depAu) decorated perylene tetracarboxylic acid (PTCA) as sensing platform. Owing to the excellent membrane-forming of PTCA and superior conductivity of depAu, the PTCA between two depAu layers can simply and effectively produce an extremely high initial photocurrent to afford a precondition for sensitive biodetection. Thereafter, the assembly of C60@C3N4 nanocomposites on electrode via typical sandwich reaction enabled the generation of a significantly decreased photocurrent. Here, the C3N4 with high surface area not only provided massive binding sites for C60 immobilization, but also partly competed with PTCA in light absorption for producing a significantly smaller photocurrent in the presence of electron donor ascorbic acid (AA). Additionally, both the C3N4 and C60 have the poor conductivity, which could inhibit the electron transfer to achieve a further decreased photocurrent, effectively improving the sensitivity of proposed biosensor. As a result, the PEC biosensor in a "signal-off" mode showed an extremely low detection limit down to 1.5 fM, providing a sensitive and universal strategy for protein detection.


Assuntos
Fulerenos/química , Grafite/química , Nanopartículas Metálicas/química , Nanocompostos/química , Compostos de Nitrogênio/química , Perileno/análogos & derivados , Trombina/análise , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Fulerenos/efeitos da radiação , Ouro/química , Grafite/efeitos da radiação , Limite de Detecção , Nanocompostos/efeitos da radiação , Compostos de Nitrogênio/efeitos da radiação , Perileno/química , Reprodutibilidade dos Testes , Raios Ultravioleta
5.
ACS Appl Mater Interfaces ; 11(30): 26581-26589, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31287647

RESUMO

Herein, we developed a nanocomposite membrane with synergistic photodynamic therapy and photothermal therapy antibacterial effects, triggered by a single near-infrared (NIR) light illumination. First, upconversion nanoparticles (UCNPs) with a hierarchical structure (UCNPs@TiO2) were synthesized, which use NaYF4:Yb,Tm nanorods as the core and TiO2 nanoparticles as the outer shell. Then, nanosized graphene oxide (GO), as a photothermal agent, was doped into UCNPs@TiO2 core-shell nanoparticles to obtain UCNPs@TiO2@GO. Afterward, the mixture of UCNPs@TiO2@GO in poly(vinylidene) fluoride (PVDF) was applied for electrospinning to generate the nanocomposite membrane (UTG-PVDF). Generation of reactive oxygen species (ROS) and changes of temperature triggered by NIR action were both investigated to evaluate the photodynamic and photothermal properties. Upon a single NIR light (980 nm) irradiation for 5 min, the nanocomposite membrane could simultaneously generate ROS and moderate temperature rise, triggering synergistic antibacterial effects against both Gram-positive and -negative bacteria, which are hard to be achieved by an individual photodynamic or photothermal nanocomposite membrane. Additionally, the as-prepared membrane can effectively restrain the inflammatory reaction and accelerate wound healing, thus exhibiting great potentials in treating infectious complications in wound healing progress.


Assuntos
Antibacterianos/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Fotoquimioterapia , Antibacterianos/farmacologia , Antibacterianos/efeitos da radiação , Bactérias Gram-Negativas/patogenicidade , Bactérias Gram-Positivas/patogenicidade , Grafite/química , Grafite/farmacologia , Humanos , Raios Infravermelhos , Nanocompostos/química , Nanocompostos/efeitos da radiação , Nanopartículas/química , Nanopartículas/efeitos da radiação , Nanopartículas/uso terapêutico , Nanotubos/química , Nanotubos/efeitos da radiação , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/uso terapêutico , Polivinil/química , Polivinil/uso terapêutico , Espécies Reativas de Oxigênio/química , Titânio/química , Titânio/farmacologia
6.
Analyst ; 144(12): 3716-3720, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31134993

RESUMO

A photothermal immune-imaging assay was innovatively designed for the visual quantitative detection of cancer biomarkers by coupling CuxS nanocrystals with a portable infrared thermal imager on a smartphone. The rolling circle amplification (RCA) technique was used for the formation of a CuxS nanocrystal concatemer, thus opening up new territories in immunoassay development.


Assuntos
Biomarcadores Tumorais/análise , Imunoensaio/métodos , Nanocompostos/química , Antígeno Prostático Específico/análise , Smartphone , Anticorpos/imunologia , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Biomarcadores Tumorais/imunologia , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Cobre/química , DNA/química , DNA/genética , Humanos , Imunoensaio/instrumentação , Raios Infravermelhos , Masculino , Nanocompostos/efeitos da radiação , Técnicas de Amplificação de Ácido Nucleico/métodos , Hibridização de Ácido Nucleico , Antígeno Prostático Específico/imunologia , Sulfetos/química , Temperatura
7.
Carbohydr Polym ; 216: 189-196, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31047056

RESUMO

In this study, the composite of carboxymethyl cellulose (CMC) film modified with gelatin and TiO2-Ag nanoparticles (CMC/Gel/TiO2-Ag) was prepared and some properties of synthesized film including physicochemical and photocatalytic properties were investigated. FT-IR results showed that new interactions between the film components were created. Scanning electron microscopy (SEM) results showed that the TiO2-Ag particles with 50-100 nm distributed in the CMC/Gelatin film. The results of the mechanical test showed that the TiO2-Ag nanoparticles at low concentrations increased tensile strength (TS) and decreased strain to break (STB), but with increasing nanoparticles concentrations, TS decreased and STB increased. Photocatalytic study showed that the prepared CMC/Gel/TiO2-Ag film has good photocatalytic property. Gas chromatography was used to study photocatalytic effects of film. Increasing TiO2-Ag nano particles on the film increases the photocatalytic activity of films against NH3, ethanol and benzene.


Assuntos
Plásticos Biodegradáveis/química , Carboximetilcelulose Sódica/química , Gelatina/química , Nanopartículas Metálicas/química , Prata/química , Titânio/química , Amônia/química , Benzeno/química , Plásticos Biodegradáveis/síntese química , Plásticos Biodegradáveis/efeitos da radiação , Carboximetilcelulose Sódica/síntese química , Carboximetilcelulose Sódica/efeitos da radiação , Catálise , Módulo de Elasticidade , Etanol/química , Gelatina/síntese química , Gelatina/efeitos da radiação , Luz , Membranas Artificiais , Nanopartículas Metálicas/efeitos da radiação , Nanocompostos/química , Nanocompostos/efeitos da radiação , Permeabilidade , Prata/efeitos da radiação , Vapor , Resistência à Tração , Titânio/efeitos da radiação , Água/química
8.
J Colloid Interface Sci ; 549: 9-15, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31015057

RESUMO

Photothermal therapy (PTT) based on photothermal effect of the gold nanostructures, has been widely applied as a noninvasive therapy approach in cancer treatment. However, bare Au nanoparticles are not stable enough during the irradiation process, and cannot harvest sufficient energy to kill tumor cells. To improve this, we have fabricated a stable bioagent by loading gold nanorods (AuNRs) into multicompartment mesoporous silica nanoparticles (MMSNs) for the photothermal therapy. The procedure is that when AuNRs entrapped in MMSNs are irradiated by a laser in the near-infrared region of 808 nm, the hyperthermia produced by the assembled composites is strong enough to damage tumor tissues directly. Both experiments in vitro and in vivo demonstrate that the nanocomposites are perfect candidates as PTT agents for the cancer treatment with a high efficiency. Furthermore, it is found that the nanocomposites have good photostability and consistent temperature fluctuation over 11 on/off cycles with irradiation which the pure AuNRs will not have.


Assuntos
Antineoplásicos/química , Ouro/química , Nanocompostos/química , Nanotubos/química , Dióxido de Silício/química , Animais , Antineoplásicos/efeitos da radiação , Antineoplásicos/uso terapêutico , Carbonato de Cálcio/química , Sobrevivência Celular/efeitos dos fármacos , Humanos , Luz , Células MCF-7 , Masculino , Camundongos Endogâmicos BALB C , Nanocompostos/efeitos da radiação , Nanocompostos/uso terapêutico , Nanotubos/efeitos da radiação , Tamanho da Partícula , Fototerapia/métodos , Porosidade , Propriedades de Superfície
9.
Molecules ; 24(5)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30832216

RESUMO

Semiconducting polymers are promising materials for photocatalysis, batteries, fuel applications, etc. One of the most useful photocatalysts is polymeric carbon nitride (PCN), which is usually produced during melamine condensation. In this work, a novel method of obtaining a PCN nanocomposite, in which PCN forms an amorphous layer coating on oxide nanoparticles, is presented. Microwave hydrothermal synthesis (MHS) was used to synthesize a homogeneous mixture of nanoparticles consisting of 80 wt.% AlOOH and 20 wt.% of ZrO2. The nanopowders were mechanically milled with melamine, and the mixture was annealed in the temperature range of 400⁻600 °C with rapid heating and cooling. The above procedure lowers PCN formation to 400 °C. The following nanocomposite properties were investigated: band gap, specific surface area, particle size, morphology, phase composition, chemical composition, and photocatalytic activity. The specific surface of the PCN nanocomposite was as high as 70 m²/g, and the optical band gap was 3 eV. High photocatalytic activity in phenol degradation was observed. The proposed simple method, as well as the low-cost preparation procedure, permits the exploitation of PCN as a polymer semiconductor photocatalytic material.


Assuntos
Catálise , Nanopartículas Metálicas/química , Nanocompostos/química , Nitrilos/química , Luz , Nanocompostos/efeitos da radiação , Óxidos/química , Processos Fotoquímicos , Polímeros/química , Difração de Raios X
10.
Int J Mol Sci ; 20(4)2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30791663

RESUMO

The rise and development of nanotechnology has enabled the creation of a wide number of systems with new and advantageous features to treat cancer. However, in many cases, the lone application of these new nanotherapeutics has proven not to be enough to achieve acceptable therapeutic efficacies. Hence, to avoid these limitations, the scientific community has embarked on the development of single formulations capable of combining functionalities. Among all possible components, silica-either solid or mesoporous-has become of importance as connecting and coating material for these new-generation therapeutic nanodevices. In the present review, the most recent examples of fully inorganic silica-based functional composites are visited, paying particular attention to those with potential biomedical applicability. Additionally, some highlights will be given with respect to their possible biosafety issues based on their chemical composition.


Assuntos
Materiais Biocompatíveis/química , Nanocompostos/química , Dióxido de Silício/química , Materiais Biocompatíveis/efeitos da radiação , Técnicas Biossensoriais , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Luz , Fenômenos Magnéticos , Teste de Materiais , Nanocompostos/efeitos da radiação , Nanotecnologia , Fotoquimioterapia , Porosidade
11.
Int J Biol Macromol ; 124: 922-930, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30502426

RESUMO

In this study, the effect of UV-C light on starch-kefiran-ZnO (1%) primary solution in different exposure times (1, 6, and 12 h) was investigated. Starch-kefiran-ZnO (SKZ) solution was modified by UV irradiation in different time periods. Also, nano-ZnO (ZN) was used as a photo-initiator and reinforcement agent, simultaneously. Mechanical properties of the films were affected after the UV treatment. The tensile strength increased because of the enhanced interaction between the biopolymer mixture and nano filler but elongation at break was decreased. WVP decreased about 16% and dwindled to 2.08 × 10-10 g m-1 s-1 Pa-1. Water related properties (i.e. moisture content, moisture absorption, and solubility in water) of the films decreased by UV-C exposure. On the other hand, UV absorption and water contact angle increased because of the better distribution of the ZNs in polymer matrix after the UV exposure. Better compatibility of the ZNs and the biopolymer matrix after UV treatment was confirmed by the SEM micrographs. Comparison of FTIR spectra before and after UV exposure showed slight shifts. It was due to some formed or deformed bonds inside of the nanocomposite matrix. The modified SKZ by UV could be an appropriate process to sanitizing and food packaging concurrently. As well as UV can be used as a nano-ZnO compatibilizer in food packaging materials.


Assuntos
Materiais Biocompatíveis/química , Nanocompostos/química , Polissacarídeos/química , Amido/química , Óxido de Zinco/química , Embalagem de Alimentos/métodos , Humanos , Nanocompostos/efeitos da radiação , Nanocompostos/ultraestrutura , Permeabilidade , Processos Fotoquímicos , Resistência à Tração , Raios Ultravioleta , Água/química
12.
Talanta ; 192: 360-367, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30348403

RESUMO

A novel composite monolithic column based on graphene oxide-trimethyl-2-methacroyloxyethylammonium chloride-titania (GO-META-TiO2) was developed for the enrichment of phosphopeptides. META was proposed as a "bridge" to connect GO and TiO2 species to prepare GO-META-TiO2 composite. This high surface area composite (surface area = 196.93 m2 g-1) was fixed in the monolithic column via an in situ UV polymerization process. In-tube solid phase microextraction (IT-SPME) using this composite was coupled with matrix-assisted laser desorption ionization time-of-flight-mass spectrometry (MALDI-TOF-MS) for the enrichment and detection of phosphorylated peptides from a digestion mixture of α-casein, ß-casein, and bovine serum albumin (BSA) in molar ratios of 1:1:1, 1:1:10, and 1:1:100. The key factors affecting the IT-SPME of the phosphopeptides, such as the elution solution concentrations, the extraction flow rate, and the elution flow rate were comprehensively investigated. For further demonstration, this method was employed for the enrichment and detection of phosphorylated peptides from digested chicken egg white. The obtained results indicated that the GO-META-TiO2 composite monolithic column rapidly and efficiently captured the phosphopeptides present in these complex biological samples, even in the 10 fmol ß-casein tryptic digest. We therefore propose that the reported GO-META-TiO2 composite monolithic column possesses a suitable affinity for the selective extraction of phosphopeptides from biological samples. This method paves a way in extending the application of nanomaterials.


Assuntos
Nanocompostos/química , Fosfopeptídeos/análise , Microextração em Fase Sólida/instrumentação , Animais , Sequência de Bases , Caseínas/química , Bovinos , Galinhas , Colina/análogos & derivados , Colina/síntese química , Colina/química , Colina/efeitos da radiação , Clara de Ovo/química , Grafite/síntese química , Grafite/química , Grafite/efeitos da radiação , Metacrilatos/síntese química , Metacrilatos/química , Metacrilatos/efeitos da radiação , Nanocompostos/efeitos da radiação , Polimerização/efeitos da radiação , Soroalbumina Bovina/química , Microextração em Fase Sólida/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Titânio/química , Titânio/efeitos da radiação , Tripsina/química , Raios Ultravioleta
13.
ACS Nano ; 13(1): 284-294, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30543399

RESUMO

Multifunctional nanoplatforms with special advantages in the diagnosis and treatment of cancer have been widely explored in nanomedicine. Herein, we synthesize two-dimensional core-shell nanocomposites (Ti3C2@Au) via a seed-growth method starting from the titanium carbide (Ti3C2) nanosheets, a classical type of MXene nanostructure. After growing gold on the surface of Ti3C2 nanosheets, the stability and biocompatibility of the nanocomposites are greatly improved by the thiol modification. Also importantly, the optical absorption in the near-infrared region is enhanced. Utilizing the ability of the high optical absorbance and strong X-ray attenuation, the synthesized Ti3C2@Au nanocomposites are used for photoacoustic and computed tomography dual-modal imaging. Importantly, the mild photothermal effect of the Ti3C2@Au nanocomposites could improve the tumor oxygenation, which significantly enhances the radiotherapy. No obvious long-term toxicity of the nanocomposites is found at the injected dose. This work highlights the promise of special properties of MXene-based multifunctional nanostructures for cancer theranostics.


Assuntos
Nanopartículas Metálicas/química , Imagem Multimodal/métodos , Nanocompostos/química , Neoplasias Experimentais/diagnóstico por imagem , Fototerapia/métodos , Radioterapia/métodos , Absorção de Radiação , Animais , Linhagem Celular Tumoral , Feminino , Ouro/química , Nanopartículas Metálicas/efeitos da radiação , Camundongos , Camundongos Endogâmicos BALB C , Nanocompostos/efeitos da radiação , Neoplasias Experimentais/terapia , Técnicas Fotoacústicas/métodos , Tomografia por Emissão de Pósitrons/métodos , Titânio/química
14.
Biomacromolecules ; 20(2): 693-704, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30358992

RESUMO

Brittleness has hindered commercialization of cellulose nanofibril (CNF) films. The use of synthetic polymers and plasticizers is a known detour that impairs biodegradability and carbon footprint of the product. Herein, we utilize a variety of softwood Kraft lignin morphologies to obtain strong and ductile CNF nanocomposite films. An optimum 10 wt % content of colloidal lignin particles (CLPs) produced films with nearly double the toughness compared to a CNF film without lignin. CLPs rendered the films waterproof, provided antioxidant activity and UV-shielding with better visible light transmittance than obtained with irregular lignin aggregates. We conclude based on electron microscopy, dynamic water sorption analysis, and tp-DSC that homogeneously distributed CLPs act as ball bearing lubricating and stress transferring agents in the CNF matrix. Overall, our results open new avenues for the utilization of lignin nanoparticles in biopolymer composites equipped with versatile functionalities for applications in food packaging, water purification, and biomedicine.


Assuntos
Lignina/química , Nanocompostos/química , Nanofibras/química , Coloides/química , Nanocompostos/efeitos da radiação , Nanofibras/efeitos da radiação , Luz Solar , Resistência à Tração , Raios Ultravioleta
15.
Environ Sci Pollut Res Int ; 26(17): 16877-16886, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29372521

RESUMO

Air pollution due to emission of various hazardous gases such as SO2 into the atmosphere and its control is an important environmental issue. Application of photocatalysts is considered as a suitable process to control the gaseous pollutants. In this study, the efficiency of clinoptilolite as a natural zeolite (Ze) modified by TiO2 (Ze-Ti) and a polymeric surfactant polyoxypropylene (Ze-Ti-POP) for removal of SO2 was investigated. The nanocomposites were characterized by SEM, EDX, and BET analyses. The photocatalytic oxidation experiments of SO2 by the nanocomposites and natural zeolite were done under UV irradiation with initial SO2 concentration of 500 ppm in a photoreactor. The effects of different factors including reaction time, catalyst dose, UV irradiation intensity, humidity content, and calcination temperature and dose of TiO2 were studied. The modification of clinoptilolite by TiO2 and POP increased considerably the BET specific surface area of the nanocomposites. The results showed that maximum removal efficiencies of SO2 by Ze-Ti and Ze-Ti-POP under the optimum experimental conditions were 82.1 and 87.4%, respectively. Adsorption kinetics data well fitted with the Langmuir-Hinshelwood model. Moreover, reusing of nanocomposites after three regeneration cycles indicated that application of Ze-Ti and Ze-Ti-POP nanocomposites could be a promising approach for SO2 removal. Graphical abstract ᅟ.


Assuntos
Poluentes Atmosféricos/química , Polímeros/química , Propilenoglicóis/química , Dióxido de Enxofre/química , Tensoativos/química , Titânio/química , Poluentes Atmosféricos/análise , Catálise , Gases , Umidade , Nanocompostos/efeitos da radiação , Oxirredução , Processos Fotoquímicos , Dióxido de Enxofre/análise , Temperatura , Titânio/efeitos da radiação , Raios Ultravioleta , Zeolitas
16.
J Control Release ; 288: 34-44, 2018 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-30171977

RESUMO

Stimuli-responsive nanomaterials have emerged as promising drug delivery systems for tumor therapy, as they can specifically respond to tumor-associated stimuli and release the loaded drugs in a controllable manner. However, most currently available stimuli-responsive nanomedicines rely on surrounding extreme stimulus to trigger the activity, which can be inefficient under dynamic and complex living conditions. Herein, we report a near-infrared (NIR) light-responsive nanocomposite, which can generate reactive oxygen species to efficiently trigger the decomposition upon NIR laser irradiation. This nanocomposite is fabricated by conjugating polyamidoamine-pluronic F68 and graphene oxide via diselenide bond, and encapsulating the NIR photosensitizer indocyanine green and chemotherapeutic drug doxorubicin (DOX) as payloads. Under NIR light, the nanocomposite shows lysosomal escape, controlled drug release, and nuclear trafficking of DOX inside multidrug resistant (MDR) MCF-7/ADR cells. Interestingly, this nanocomposite effectively down-regulates ABCB1 gene and P-glycoprotein of MCF-7/ADR cells, exhibiting significant cytotoxicity. In vivo anti-tumor study demonstrates an effective accumulation and superior therapeutic efficacy of this multifunctional nanocomposite in MCF-7/ADR tumors, representing a great potential for clinical treatment of MDR cancer.


Assuntos
Nanocompostos/administração & dosagem , Nanocompostos/efeitos da radiação , Neoplasias/terapia , Fototerapia , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Grafite/administração & dosagem , Grafite/química , Humanos , Verde de Indocianina/administração & dosagem , Verde de Indocianina/química , Células MCF-7 , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanocompostos/química , Neoplasias/metabolismo , Óxidos/administração & dosagem , Óxidos/química , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/química , Poloxâmero/administração & dosagem , Poloxâmero/química , Poliaminas/administração & dosagem , Poliaminas/química , Espécies Reativas de Oxigênio/metabolismo , Distribuição Tecidual
17.
Inorg Chem ; 57(16): 10180-10188, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30088933

RESUMO

Phototherapy, including photothermal therapy (PTT)/photodynamic therapy (PDT), is usually considered as a promising strategy for cancer treatment due to its noninvasive and selective therapeutic effect by laser irradiation. A light-activatable nanoplatform based on bovine serum albumin (BSA)-coated Bi2Te3 nanosheets conjugated with methylene blue (MB) was successfully designed and constructed for bimodal PTT/PDT combination therapy. The resultant nanoconstruct (BSA-Bi2Te3/MB) exhibited high stability in various physiological solutions and excellent biocompatibility. Especially, the nanoconstruct not only possessed strong near-infrared absorption and high photothermal conversion as a photothermal agent for efficient tumor ablation but also could successfully load photosensitizer for PDT of tumor. When exposed to laser irradiation, tumors in mice with BSA-Bi2Te3/MB injection were completely eliminated without recurrence within 15 d, demonstrating the potential of the nanoconstruct as a bimodal PTT/PDT therapeutic platform for cancer treatment.


Assuntos
Antineoplásicos/uso terapêutico , Azul de Metileno/uso terapêutico , Nanocompostos/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Adsorção , Animais , Antineoplásicos/química , Antineoplásicos/efeitos da radiação , Antineoplásicos/toxicidade , Bismuto/química , Bovinos , Feminino , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Azul de Metileno/química , Azul de Metileno/efeitos da radiação , Azul de Metileno/toxicidade , Camundongos , Nanocompostos/química , Nanocompostos/efeitos da radiação , Nanocompostos/toxicidade , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Fármacos Fotossensibilizantes/toxicidade , Soroalbumina Bovina/química , Oxigênio Singlete/metabolismo , Telúrio/química
18.
Langmuir ; 34(34): 9974-9981, 2018 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-30056720

RESUMO

A pH- and ultrasound dual-responsive drug release pattern was successfully achieved using mesoporous silica nanoparticles (MSNs) coated with polydopamine (PDA). In this paper, the PDA shell on the MSN surface was obtained through oxidative self-polymerization under the alkaline condition. The morphology and structure of this composite nanoparticle were fully characterized by a series of analyses, such as infrared (IR), transmission electron microscopy, and thermogravimetric analysis. Doxorubicin hydrochloride (DOX)-loaded composite nanoparticles were used to study the performances of responsive drug storage/release behavior, and this kind of hybrid material displayed an apparent pH response in DOX releasing under the acidic condition. Beyond that, upon high-intensity focused ultrasound exposure, loaded DOX in composite nanoparticles was successfully triggered to release from pores because of the ultrasonic cavitation effect, and the DOX-releasing pattern could be optimized into a unique pulsatile fashion by switching the on/off status. From the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, it was observed that our blank nanoparticles showed no toxicity to HeLa cells, but DOX-loaded nanoparticles could inhibit the growth of tumor cells. Furthermore, these composite nanoparticles displayed an effective near-IR photothermal conversion capability with a relatively high conversion efficiency (∼37%). These as-desired drug delivery carriers might have a great potential for future cancer treatment that combine the chemotherapy and photothermal therapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Indóis/química , Nanopartículas/química , Polímeros/química , Dióxido de Silício/química , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/toxicidade , Doxorrubicina/química , Doxorrubicina/toxicidade , Portadores de Fármacos/efeitos da radiação , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Células HeLa , Humanos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Indóis/síntese química , Indóis/efeitos da radiação , Indóis/toxicidade , Raios Infravermelhos , Nanocompostos/química , Nanocompostos/efeitos da radiação , Nanocompostos/toxicidade , Nanopartículas/efeitos da radiação , Nanopartículas/toxicidade , Polímeros/síntese química , Polímeros/efeitos da radiação , Polímeros/toxicidade , Porosidade , Dióxido de Silício/síntese química , Dióxido de Silício/efeitos da radiação , Dióxido de Silício/toxicidade , Ondas Ultrassônicas
19.
Int J Mol Sci ; 19(6)2018 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-29914214

RESUMO

Chitosan (CS) is a natural polymer derived from chitin that has found its usage both in research and commercial applications due to its unique solubility and chemical and biological attributes. The biocompatibility and biodegradability of CS have helped researchers identify its utility in the delivery of therapeutic agents, tissue engineering, wound healing, and more. Industrial applications include cosmetic and personal care products, wastewater treatment, and corrosion protection, to name a few. Many researchers have published numerous reviews outlining the physical and chemical properties of CS, as well as its use for many of the above-mentioned applications. Recently, the cationic polyelectrolyte nature of CS was found to be advantageous for stabilizing fascinating photonic materials including plasmonic nanoparticles (e.g., gold and silver), semiconductor nanoparticles (e.g., zinc oxide, cadmium sulfide), fluorescent organic dyes (e.g., fluorescein isothiocyanate (FITC)), luminescent transitional and lanthanide complexes (e.g., Au(I) and Ru(II), and Eu(III)). These photonic systems have been extensively investigated for their usage in antimicrobial, wound healing, diagnostics, sensing, and imaging applications. Highlighted in this review are the different works involving some of the above-mentioned molecular-nano systems that are prepared or stabilized using the CS polymer. The advantages and the role of the CS for synthesizing and stabilizing the above-mentioned optically active materials have been illustrated.


Assuntos
Técnicas Biossensoriais/métodos , Quitosana/análogos & derivados , Luz , Nanopartículas/química , Óptica e Fotônica/métodos , Quitosana/efeitos da radiação , Nanocompostos/química , Nanocompostos/efeitos da radiação , Nanopartículas/efeitos da radiação
20.
J Hazard Mater ; 354: 54-62, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29727790

RESUMO

Development of biocompatible photocatalysts with improved charge separation and high selectivity is essential for effective removal of air pollutants. Iron-containing catalysts have attracted extensive attention due to their low-toxicity and high natural abundance. Here, carbon quantum dots (CQDs) modified FeOOH nanocomposites fabricated using a facile hydrothermal route showed enhanced NO removal efficiency (22%) compared to pure FeOOH. Moreover, generation of toxic NO2 intermediates was significantly inhibited using the nanocomposites, demonstrating high selectivity for final nitrate formation. Photo-electrochemical results showed that both charge separation and transfer efficiency were significantly improved by CQDs addition, and the lifetime of photo-generated carriers was increased eventually. Density functional theory calculations further elucidated that the suppressed recombination of photo-induced electron-hole pairs was due to enhanced electron migration from the FeOOH to CQDs. A NO degradation mechanism was proposed based on detection of the reactive oxygen species using electron paramagnetic spectroscopy. In addition, the nanocomposite showed good biocompatibility and low cytotoxity, ensuring minimal environmental impact for potential application in large-scale.


Assuntos
Poluentes Atmosféricos/química , Carbono , Compostos Férricos , Nanocompostos , Óxidos de Nitrogênio/química , Pontos Quânticos , Células A549 , Poluição do Ar/prevenção & controle , Carbono/química , Carbono/efeitos da radiação , Carbono/toxicidade , Catálise , Sobrevivência Celular/efeitos dos fármacos , Compostos Férricos/química , Compostos Férricos/efeitos da radiação , Compostos Férricos/toxicidade , Humanos , Luz , Nanocompostos/química , Nanocompostos/efeitos da radiação , Nanocompostos/toxicidade , Pontos Quânticos/química , Pontos Quânticos/efeitos da radiação , Pontos Quânticos/toxicidade
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