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1.
J Photochem Photobiol B ; 223: 112298, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34474299

RESUMO

In this paper, the photodynamic effect of a ternary nanocomposite (TiO2-Ag/graphene) on Escherichia coli bacteria and two human cell lines: A375 (melanoma) and HaCaT (keratinocyte) after exposure to different wavelength domains (blue, green or red-Light Emitting Diode, LED) was analyzed. The results obtained through bioassays were correlated with the morphological, structural and spectral data obtained through FT-IR, XPS and UV-Vis spectroscopy, powder X-Ray diffractometry (XRD) and STEM/EDX techniques, leading to conclusions that showed different photodynamic activation mechanisms and effects on bacteria and human cells, depending on the wavelength. The nanocomposite proved a therapeutic potential for blue light-activated antibacterial treatment and revealed a keratinocyte cytotoxic effect under blue and green LEDs. The red light-nanocomposite duo gave a metabolic boost to normal keratinocytes and induced stasis to melanoma cells. The light and nanocomposite combination could be a potential therapy for bacterial keratosis or for skin tumors.


Assuntos
Escherichia coli/efeitos da radiação , Grafite/química , Luz , Nanocompostos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Queratinócitos/patologia , Queratinócitos/efeitos da radiação , Ceratose/tratamento farmacológico , Ceratose/patologia , Nanocompostos/química , Nanocompostos/uso terapêutico , Prata/química , Titânio/química
2.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443341

RESUMO

In recent decades, the number of patients requiring biocompatible and resistant implants that differ from conventional alternatives dramatically increased. Among the most promising are the nanocomposites of biopolymers and nanomaterials, which pretend to combine the biocompatibility of biopolymers with the resistance of nanomaterials. However, few studies have focused on the in vivo study of the biocompatibility of these materials. The electrospinning process is a technique that produces continuous fibers through the action of an electric field imposed on a polymer solution. However, to date, there are no reports of chitosan (CS) and polyvinyl alcohol (PVA) electrospinning with carbon nano-onions (CNO) for in vivo implantations, which could generate a resistant and biocompatible material. In this work, we describe the synthesis by the electrospinning method of four different nanofibrous membranes of chitosan (CS)/(PVA)/oxidized carbon nano-onions (ox-CNO) and the subdermal implantations after 90 days in Wistar rats. The results of the morphology studies demonstrated that the electrospun nanofibers were continuous with narrow diameters (between 102.1 nm ± 12.9 nm and 147.8 nm ± 29.4 nm). The CS amount added was critical for the diameters used and the successful electrospinning procedure, while the ox-CNO amount did not affect the process. The crystallinity index was increased with the ox-CNO introduction (from 0.85% to 12.5%), demonstrating the reinforcing effect of the nanomaterial. Thermal degradation analysis also exhibited reinforcement effects according to the DSC and TGA analysis, with the higher ox-CNO content. The biocompatibility of the nanofibers was comparable with the porcine collagen, as evidenced by the subdermal implantations in biological models. In summary, all the nanofibers were reabsorbed without a severe immune response, indicating the usefulness of the electrospun nanocomposites in biomedical applications.


Assuntos
Carbono/química , Quitosana/química , Eletricidade , Teste de Materiais , Membranas Artificiais , Nanocompostos/química , Álcool de Polivinil/química , Animais , Nanocompostos/toxicidade , Oxirredução , Ratos
3.
J Photochem Photobiol B ; 222: 112274, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34330082

RESUMO

Photodynamic therapy (PDT) has gained much attention in tumor therapy because of its special advantages. PDT heavily depends on the oxygen, yet the tumor microenvironment (TME) is a hypoxic and acid milieu, which weakens the PDT effect. Based on the consideration that the TME deteriorated by the PDT oxygen consumption could activate the hypoxic-sensitive small-molecule drug, we designed and prepared an integrated nanocomposite including zirconium ion metal organic framework (carrier), pyropheophorbide-a (PPa, photosensitizer), and 6-amino flavone (AF, hypoxic-sensitive drug), aiming to exert a cascaded PDT-chemotherapy (CT) antitumor effect and to solve the hypoxic challenge. The prepared nanocomposite showed great stability under the physiological (pH 7.4) condition and could continuously release PPa and AF under slightly acidic pH condition (pH 6.4), suggesting a tumor microenvironment responsive feature. Systematical in vitro and in vivo researches under various conditions (light, dark, hypoxic and normoxic) have showed that the obtained Zr-MOF@PPa/AF@PEG nanoparticles (NPs) had good biocompatibility and could achieve efficient antitumor effects based on PDT- chemotherapy (CT) cascade process. Finally, bright red fluorescence was observed in the tumor cells after internalization implying an application potential in tumor imaging.


Assuntos
Clorofila/análogos & derivados , Flavonoides/química , Estruturas Metalorgânicas/química , Nanocompostos/química , Fotoquimioterapia/métodos , Nanomedicina Teranóstica , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Clorofila/química , Clorofila/metabolismo , Clorofila/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Flavonoides/metabolismo , Flavonoides/uso terapêutico , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nanocompostos/uso terapêutico , Nanocompostos/toxicidade , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Polietilenoglicóis/química , Oxigênio Singlete/metabolismo , Microambiente Tumoral , Zircônio/química
4.
ACS Appl Mater Interfaces ; 13(26): 31193-31205, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34164984

RESUMO

Owing to the rise in prevalence of multidrug-resistant pathogens attributed to the overuse of antibiotics, infectious diseases caused by the transmission of microbes from contaminated surfaces to new hosts are an ever-increasing threat to public health. Thus, novel materials that can stem this crisis, while also functioning via multiple antimicrobial mechanisms so that pathogens are unable to develop resistance to them, are in urgent need. Toward this goal, in this work, we developed in situ grown bacterial cellulose/MoS2-chitosan nanocomposite materials (termed BC/MoS2-CS) that utilize synergistic membrane disruption and photodynamic and photothermal antibacterial activities to achieve more efficient bactericidal activity. The BC/MoS2-CS nanocomposite exhibited excellent antibacterial efficacy, achieving 99.998% (4.7 log units) and 99.988% (3.9 log units) photoinactivation of Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, respectively, under visible-light illumination (xenon lamp, 500 W, λ ≥ 420 nm, and 30 min). Mechanistic studies revealed that the use of cationic chitosan likely facilitated bacterial membrane disruption and/or permeability, with hyperthermia (photothermal) and reactive oxygen species (photodynamic) leading to synergistic pathogen inactivation upon visible-light illumination. No mammalian cell cytotoxicity was observed for the BC/MoS2-CS membrane, suggesting that such composite nanomaterials are attractive as functional materials for infection control applications.


Assuntos
Antibacterianos/farmacologia , Dissulfetos/farmacologia , Molibdênio/farmacologia , Nanocompostos/química , Fármacos Fotossensibilizantes/farmacologia , Animais , Antibacterianos/química , Antibacterianos/efeitos da radiação , Antibacterianos/toxicidade , Linhagem Celular , Celulose/química , Celulose/toxicidade , Quitosana/química , Quitosana/toxicidade , Dissulfetos/química , Dissulfetos/efeitos da radiação , Dissulfetos/toxicidade , Escherichia coli/efeitos dos fármacos , Calefação , Luz , Membranas Artificiais , Camundongos , Testes de Sensibilidade Microbiana , Molibdênio/química , Molibdênio/efeitos da radiação , Molibdênio/toxicidade , Nanocompostos/efeitos da radiação , Nanocompostos/toxicidade , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Fármacos Fotossensibilizantes/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos
5.
Sci Total Environ ; 784: 147221, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34088078

RESUMO

Semiconductor nanomaterials not only bring great convenience to peoples lives but also become a potential hazard to human health. The purpose of this study was to evaluate the toxicity of CuS/CdS nanocomposites in hepatocytes and mice liver. The CuS/CdS semiconductor nanocomposites were synthesized by a biomimetic synthesis - ion exchange strategy. Nanosize was confirmed by high-resolution transmission electron microscopy and dynamic light scattering. The composition and physical properties were measured by powder X-ray diffraction, Fourier transform infrared spectra, atomic absorption spectroscopy, thermogravimetry-differential scanning calorimetry and zeta potential analysis. The results revealed that CuS/CdS nanocomposites had 8.7 nm diameter and negative potential. Ion exchange time could adjust the ratio of CuS and CdS in nanocomposites. The toxicological study revealed that CuS/CdS nanocomposites could be internalized into liver cells, inhibited endogenous defense system (e.g. GSH and SOD), induced the accumulation of oxidation products (e.g. ROS, GSSG and MDA), and caused hepatocyte apoptosis. The in vivo experiments in Balb/c mice showed that the experimental dose (4 mg/kg) didn't cause observable changes in mice behavior, physical activity and pathological characteristics, but the continuous accumulation of Cd2+ in the liver and kidney might be responsible for its long-term toxicity.


Assuntos
Nanocompostos , Animais , Cobre , Hepatócitos , Fígado , Camundongos , Nanocompostos/toxicidade , Semicondutores , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
J Photochem Photobiol B ; 219: 112202, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33946027

RESUMO

This article reports the synthesis of a novel ternary Visible-Light-Driven (VLD) photocatalyst and antibacterial agent. The two-dimensional graphitic carbon nitride nanosheets (g-C3N4 NSs) and 7% molybdenum doped zinc oxide nanoparticles (Mo doped ZnO NPs) were used for the synthesis of the 65% g-C3N4 hybridized with 7% Mo doped ZnO novel ternary nanocomposite (Mo doped ZnO/g-C3N4 ternary NC). The synthesis process, as well as the structures, morphologies, photocatalytic and antibacterial properties of the synthesized ternary NC and constituents, were investigated by using several spectroscopic and microscopic techniques. It was revealed through the Transmission Electron Microscopy (TEM) characterization of the synthesized NC that the Mo doped ZnO NPs were found uniformly embedded upon the well-stacked g-C3N4NSs. It was further discovered by the bandgap analysis that the light absorbance ability of the ternary NC exists in the visible region of the light spectrum. The photocatalytic degradation of the methylene blue (MB) by the use of novel ternary NC in an aqueous medium was analyzed while using Ultra Violet-Visible (UV-Visible) spectroscopy. Trapping experiments of active species during the photodegradation and Electron Spin Resonance (ESR) experiment revealed that the superoxide and hydroxyl radicals were the leading species liable for MB deterioration. The ternary NC exhibited superior photocatalytic performance as compared with binary doped or hybridized nanomaterials (NMs) and mono photocatalysts due to the facility of effective migration and separation of the charge carriers across the (Mo doped ZnO NPs)/g-C3N4 NSs interface of the heterojunction. The increased generation of the reactive oxygen species (ROS), O2-, and •OH radicals the photogenerated charge carriers within the Mo doped ZnO/g-C3N4 NC were found responsible for its enhanced antibacterial performance.


Assuntos
Antibacterianos/síntese química , Grafite/química , Luz , Nanocompostos/química , Compostos de Nitrogênio/química , Fotólise/efeitos da radiação , Óxido de Zinco/química , Antibacterianos/farmacologia , Catálise , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Radical Hidroxila/química , Nanopartículas Metálicas/química , Azul de Metileno/química , Molibdênio/química , Nanocompostos/toxicidade
7.
J Photochem Photobiol B ; 219: 112201, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33962112

RESUMO

In this project, we studied the thermal and chemical method for the synthesis of carbon dots (CDs)/Hematite (α-Fe2O3) quantum dots and the preparation of hydroxypropyl cellulose cross-linked chitosan (HPCCS) and ulvan (UN) was performed by chemical method. Carbon dots/α-Fe2O3 quantum dots with size distribution of 3-5 nm were completely encapsulated in the HPCCS/UN NPs to obtain composites, which indicated unique characteristics with respect to antimicrobial, pH-responsive and optical properties. The CDs-HQDs/HPCCS/UN nanocomposites exhibited a single-excitation (440 nm), dual-emission fluorescence property (505 nm and 628 nm for green and red light from CDs-HQDs and HPCCS/UN NPs). The nanocomposites played as a pH-responsive drug delivery process to release ulvan at a fast rate in pH 7.4 buffer solution but at a slow rate in low pH solutions. The CDs-HQDs/HPCCS/UN nanocomposites gained the highest photocatalytic activity for degrading 4-chlorophenol (4-CPh) as a pollutant (>98% during 70 min under sunlight irradiation). Moreover, the nanocomposites indicated great inhibitory influences towards bacterial and fungal.


Assuntos
Anti-Infecciosos/química , Celulose/análogos & derivados , Quitosana/química , Nanocompostos/química , Pontos Quânticos/química , Luz Solar , Anti-Infecciosos/farmacologia , Carbono/química , Catálise , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Celulose/química , Clorofenóis/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos/efeitos da radiação , Escherichia coli/efeitos dos fármacos , Compostos Férricos/química , Humanos , Concentração de Íons de Hidrogênio , Nanocompostos/toxicidade , Staphylococcus aureus/efeitos dos fármacos , Poluentes Químicos da Água/química
8.
Chemosphere ; 277: 130160, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33794434

RESUMO

Advanced investigations on the use of graphene based nanomaterials have highlighted the capacity of these materials for wastewater treatment. Research on this topic revealed the efficiency of the nanocomposite synthetized by graphene oxide functionalized with polyethyleneimine (GO-PEI) to adsorb mercury (Hg) from contaminated seawater. However, information on the environmental risks associated with these approaches are still lacking. The focus of this study was to evaluate the effects of Hg in contaminated seawater and seawater remediated by GO-PEI, using the species Ruditapes philippinarum, maintained at two different warming scenarios: control (17 °C) and increased (22 °C) temperatures. The results obtained showed that organisms exposed to non-contaminated and remediated seawaters at control temperature presented similar biological patterns, with no considerable differences expressed in terms of biochemical and histopathological alterations. Moreover, the present findings revealed increased toxicological effects in clams under remediated seawater at 22 °C in comparison to those subjected to the equivalent treatment at 17 °C. These results confirm the capability of GO-PEI to adsorb Hg from water with no noticeable toxic effects, although temperature could alter the responses of mussels to remediated seawater. These materials seem to be a promise eco-friendly approach to remediate wastewater, with low toxicity evidenced by remediated seawater and high regenerative capacity of this nanomaterial, keeping its high removal performance after successive sorption-desorption cycles.


Assuntos
Bivalves , Grafite , Mercúrio , Nanocompostos , Poluentes Químicos da Água , Animais , Grafite/toxicidade , Laboratórios , Mercúrio/toxicidade , Nanocompostos/toxicidade , Água do Mar , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
9.
Carbohydr Polym ; 260: 117835, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712172

RESUMO

Bacterial breeding is the main cause of food perishability, which is harmful to human health. Silver nanoparticles (AgNPs) are one of the most widely used antimicrobial agents, but they are easy to release and cause cumulative toxicity. In this work, with corn stalk as green reductant and GO as template, a simple electrostatic self-assembled sandwich-like chitosan (CS) wrapped rGO@AgNPs nanocomposite film (CS/rGO@AgNPs) was synthesized to achieve stabilizing and controlled-release of AgNPs. The results showed that the the CS/rGO@AgNPs film continued releasing AgNPs for up to 14 days, and the final release amount of silver nanoparticles was only about 1.9 %. More importantly, the nanocomposite film showed durable antibacterial effect and good antibacterial activity against E. coli and S. aureus, and they showed no toxicity to cells. Hence, the nanocomposite film has potential application as an effective and safe packaging material to prolong the shelf life of food products.


Assuntos
Antibacterianos/química , Quitosana/química , Grafite/química , Nanopartículas Metálicas/química , Nanocompostos/química , Antibacterianos/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Escherichia coli/efeitos dos fármacos , Humanos , Nanocompostos/toxicidade , Prata/química , Solubilidade , Staphylococcus aureus/efeitos dos fármacos , Resistência à Tração
10.
Carbohydr Polym ; 260: 117772, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712130

RESUMO

Nanoparticle-polymer composites are important functional materials but structural control of their assembly is challenging. Owing to its crystalline internal structure and tunable nanoscale morphology, cellulose is promising polymer scaffold for templating such composite materials. Here, we show bottom-up synthesis of reducing end thiol-modified cellulose chains by iterative bi-enzymatic ß-1,4-glycosylation of 1-thio-ß-d-glucose (10 mM), to a degree of polymerization of ∼8 and in a yield of ∼41% on the donor substrate (α-d-glucose 1-phosphate, 100 mM). Synthetic cellulose oligomers self-assemble into highly ordered crystalline (cellulose allomorph II) material showing long (micrometers) and thin nanosheet-like morphologies, with thickness of 5-7 nm. Silver nanoparticles were attached selectively and well dispersed on the surface of the thiol-modified cellulose, in excellent yield (≥ 95%) and high loading efficiency (∼2.2 g silver/g thiol-cellulose). Examined against Escherichia coli and Staphylococcus aureus, surface-patterned nanoparticles show excellent biocidal activity. Bottom-up approach by chemical design to a functional cellulose nanocomposite is presented. Synthetic thiol-containing nanocellulose can expand the scope of top-down produced cellulose materials.


Assuntos
Antibacterianos/química , Celulose/química , Nanopartículas Metálicas/química , Nanocompostos/química , Compostos de Sulfidrila/química , Antibacterianos/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Escherichia coli/efeitos dos fármacos , Nanocompostos/toxicidade , Prata/química , Staphylococcus aureus/efeitos dos fármacos
11.
Food Chem ; 354: 129492, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33756322

RESUMO

Gelatin and tragacanth were employed to fabricate antimicrobial nanocomposites with 1, 3, and 5% zinc oxide nanoparticles (ZnO-NPs). FT-IR and XRD proved new chemical interactions among GEL/TGC/ZnO-NPs and higher crystallinity of nanocomposites, respectively. DSC showed a significant increase in melting point temperature (Tm) from ~ 90 to ~ 93-101 °C after adding 1-5% ZnO-NPs. Ultimate tensile strength (UTS) was remarkably increased to 31.21, 34.57, and 35.06 MPa, as well as Young's Modulus to 287.44, 335.47, and 367.04 MPa after incorporating 1, 3, and 5% ZnO-NPs. The ZnO-NPs dose-dependently reduced the water vapor permeability (WVP) of the films. FE-SEM analysis from surface and cross-section illustrated the compact and homogenous structure of the nanocomposites even up to 5% ZnO-NPs. The ZnO-NPs-containing nanocomposites had a good antimicrobial activity (~10-20 mm) against both Staphylococcus aureus and Escherichia coli. Generally, the results indicated that the prepared nanocomposite films are promising antimicrobial bio-materials for food packaging.


Assuntos
Anti-Infecciosos/química , Embalagem de Alimentos/métodos , Gelatina/química , Nanocompostos/química , Tragacanto/química , Óxido de Zinco/química , Anti-Infecciosos/farmacologia , Varredura Diferencial de Calorimetria , Cor , Escherichia coli/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanocompostos/toxicidade , Permeabilidade/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Resistência à Tração , Água/química
12.
J Hazard Mater ; 415: 125605, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-33735765

RESUMO

Nickel selenide nanomaterials (NiSe2 NMs) with different vacancies demonstrated high catalytic activity as electrocatalyst in oxygen evolution reaction. As the growing needs of the industrial applications in electrocatalyst, the increased occupational exposure and environmental releasing of NMs would be unavoidable. While, much efforts have been made to evaluate the ecological safety of such engineered NMs at unrealistically high concentrations, failed to provide the comprehensively guideline for exposure thresholds. To supplement the current knowledge gap, we testified the cytotoxicity of NiSe2/rGO nanocomposites with different surface defects under more realistic exposure mode. Compared with the short-term exposure and repetitive exposure, rat lung macrophages exhibited the augmented oxidative stress, dysfunction of mitochondria, damage of DNA and disorder of calcium homeostasis under the long-term NiSe2/rGO exposure. Noteworthily, no significant differences could be found between the NiSe2/rGO with different surface defects, indicated that the defect type of NMs were not the accurate predictor for real risk assessment. Collectively, the study provided the real potential toxic effects and exposure thresholds of NMs that might be highly possible industrial produced, and appealed the new insight for risk assessments of engineered NMs under the long-term exposure, which exhibited difference from the traditional evaluation of short-term and repetitive exposure.


Assuntos
Grafite , Nanocompostos , Animais , Nanocompostos/toxicidade , Estresse Oxidativo , Ratos , Medição de Risco
13.
ChemistryOpen ; 10(4): 408-413, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33605540

RESUMO

A novel method for the preparation of antitumor drug vehicles has been optimized. Biological materials of chitosan oligosaccharide (CO) and γ-polyglutamic acid (γ-PGA) have previously been employed as modifiers to covalently modify graphene oxide (GO), which in turn loaded doxorubicin (DOX) to obtain a nano drug delivery systems of graphene oxide based composites (GO-CO-γ-PGA-DOX). The system was not equipped with the ability of initiative targeting, thus resulting into toxicity and side effects on normal tissues or organs. In order to further improve the targeting property of the system, the nucleic acid aptamer NH2 -AS1411 (APT) of targeted nucleolin (C23) was used to conjugate on GO-CO-γ-PGA to yield the targeted nano drug delivery system APT-GO-CO-γ-PGA. The structure, composition, dispersion, particle size and morphology properties of the synthesized complex have been studied using multiple characterization methods. Drug loading and release profile data showed that APT-GO-CO-γ-PGA is provided with high drug loading capacity and is capable of controlled and sustained release of DOX. Cell experimental results indicated that since C23 was overexpressed on the surface of Hela cells but not on the surface of Beas-2B cells, APT-GO-CO-γ-PGA-DOX can target Hela cells and make increase toxicity to Hela cells than Beas-2B cells, and the IC50 value of APT-GO-CO-γ-PGA-DOX was 3.23±0.04 µg/mL. All results proved that APT-GO-CO-γ-PGA can deliver antitumor drugs in a targeted manner, and achieve the effect of reducing poison, which indicated that the targeted carrier exhibits a broad application prospect in the field of biomedicine.


Assuntos
Antineoplásicos/farmacologia , Aptâmeros de Nucleotídeos/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Grafite/química , Nanocompostos/química , Oligodesoxirribonucleotídeos/química , Aptâmeros de Nucleotídeos/toxicidade , Quitina/análogos & derivados , Quitina/química , Quitina/toxicidade , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Grafite/toxicidade , Células HeLa , Humanos , Ácidos Nucleicos Imobilizados/química , Ácidos Nucleicos Imobilizados/toxicidade , Nanocompostos/toxicidade , Oligodesoxirribonucleotídeos/toxicidade , Ácido Poliglutâmico/análogos & derivados , Ácido Poliglutâmico/química , Ácido Poliglutâmico/toxicidade
14.
ACS Appl Mater Interfaces ; 13(9): 10878-10890, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33635062

RESUMO

In order to solve two issues of chlorine-resistant bacteria (CRB) and disinfection byproducts (DBPs) in tap water after the chlorine-containing treatment process, an innovative core-sheath nanostructured Cu/Cu2O-ZnO-Fe3O4 was designed and synthesized. The fabrication mechanism of the materials was then systematically analyzed to determine the component and valence state. The properties of CRB inactivation together with trichloroacetic acid (TCAA) photodegradation by Cu/Cu2O-ZnO-Fe3O4 were investigated in detail. It was found that Cu/Cu2O-ZnO-Fe3O4 displayed excellent antibacterial activity with a relatively low cytotoxicity concentration due to its synergism of nanowire structure, ion release, and reactive oxygen species generation. Furthermore, the Cu/Cu2O-ZnO-Fe3O4 nanocomposite also exhibited outstanding photocatalytic degradation activity on TCAA under simulated sunlight irradiation, which was verified to be dominated by the surface reaction through kinetic analysis. More interestingly, the cell growth rate of Cu/Cu2O-ZnO-Fe3O4 was determined to be 50% and 10% higher than those of Cu/Cu2O and Cu/Cu2O-ZnO after 10 h incubation, respectively, manifesting a weaker cytotoxicity. Therefore, the designed Cu/Cu2O-ZnO-Fe3O4 could be a promising agent for tap water treatment.


Assuntos
Antibacterianos/farmacologia , Cobre/farmacologia , Nanopartículas de Magnetita/química , Nanocompostos/química , Ácido Tricloroacético/química , Óxido de Zinco/farmacologia , Antibacterianos/química , Antibacterianos/efeitos da radiação , Antibacterianos/toxicidade , Bactérias/efeitos dos fármacos , Catálise/efeitos da radiação , Cobre/química , Cobre/efeitos da radiação , Células HeLa , Humanos , Nanopartículas de Magnetita/efeitos da radiação , Nanopartículas de Magnetita/toxicidade , Testes de Sensibilidade Microbiana , Nanocompostos/efeitos da radiação , Nanocompostos/toxicidade , Oxirredução , Fotólise/efeitos da radiação , Esterilização/métodos , Luz Solar , Purificação da Água/métodos , Óxido de Zinco/química , Óxido de Zinco/efeitos da radiação , Óxido de Zinco/toxicidade
15.
Int J Nanomedicine ; 16: 775-788, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33574665

RESUMO

Background: Intracerebral hemorrhage (ICH) is a common neurological crisis leading to high mortality and morbidity. Oxidative stress-induced secondary injury plays a critical role in neurological deterioration. Previously, we synthesized a porous Se@SiO2 nanocomposite and identified their therapeutic role in osteonecrosis of the femoral head. Whether this nanocomposite is neuroprotective remains to be elucidated. Methods: A porous Se@SiO2 nanocomposite was synthesized, and its biosafety was determined using a CCK-8 assay. The neuroprotective effect was evaluated by TUNEL staining, and intracellular ROS were detected with a DCFH-DA probe in SH-SY5Y cells exposed to hemin. Furthermore, the effect of the nanocomposite on cell apoptosis, brain edema and blood-brain barrier permeability were evaluated in a collagenase-induced ICH mouse model. The potential mechanism was also explored. Results: The results demonstrated that Se@SiO2 treatment significantly improved neurological function, increased glutathione peroxidase activity and downregulated malonaldehyde levels. The proportion of apoptotic cells, brain edema and blood-brain barrier permeability were reduced significantly in ICH mice treated with Se@SiO2 compared to vehicle-treated mice. In vitro, Se@SiO2 protected SH-SY5Y cells from hemin-induced apoptosis by preventing intracellular reactive oxygen species accumulation. Conclusion: These results suggested that the porous Se@SiO2 nanocomposite exerted neuroprotection by suppressing oxidative stress. Se@SiO2 may be a potential candidate for the clinical treatment of ICH and oxidative stress-related brain injuries.


Assuntos
Encéfalo/patologia , Hemorragia Cerebral/patologia , Nanocompostos/química , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Selênio/farmacologia , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Encéfalo/efeitos dos fármacos , Edema Encefálico/complicações , Edema Encefálico/tratamento farmacológico , Linhagem Celular Tumoral , Hemorragia Cerebral/complicações , Hemorragia Cerebral/tratamento farmacológico , Citoproteção/efeitos dos fármacos , Modelos Animais de Doenças , Hemina/toxicidade , Humanos , Masculino , Malondialdeído/metabolismo , Camundongos Endogâmicos C57BL , Nanocompostos/toxicidade , Nanocompostos/ultraestrutura , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Selênio/uso terapêutico , Dióxido de Silício/farmacologia , Testes de Toxicidade
16.
Environ Res ; 195: 110787, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33508257

RESUMO

The study was undertaken to design SnO2/Fe3O4 nanocomposite by sonochemical method and to assess the photodegradation of organic dye. Textural, composition and structural features of the bare SnO2 and SnO2/Fe3O4 samples were characterized using scanning electron microscope (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The X-ray diffraction of as-synthesized SnO2/Fe3O4 nanocomposites confirms the presence of tetragonal and cubic structure. The results disclose that the incorporation of Fe3O4 in SnO2 decrease the crystallite size and increase the surface area compared with bare SnO2 nanoparticle. The as-prepared photocatalyst shows higher efficiency than the bare SnO2 under sunlight irradiation. Vigna radiata seeds (VR), Artemia salina (AS) and Zebra fish (Danio rerio (DR) were used to check the toxicity level of the treated and untreated Rhodamine B (RhB) dye solution. These models displayed good consistency for examining the harmfulness of the solutions. The results suggests SnO2/Fe3O4 nanocomposite exhibited a good efficacy in the dye wastewater treatment. Further, the degradation efficiency was confirmed by the toxicity examination.


Assuntos
Nanocompostos , Vigna , Animais , Artemia , Catálise , Nanocompostos/toxicidade , Peixe-Zebra
17.
Chemosphere ; 265: 129089, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33261841

RESUMO

Herein, degradation of ofloxacin (OFX) by pulsed discharge plasma (PDP) coupled with multi-catalysis using graphene-Fe3O4 nanocomposites was inspected. The graphene-Fe3O4 nanocomposites were prepared by hydrothermal synthesis, and their morphology, specific surface area, chemical bond structure and magnetic property were characterized systematically. Compared with sole Fe3O4, the specific surface area of graphene-Fe3O4 nanocomposites increased from 26.34 m2/g to 125.04 m2/g. The prepared graphene-Fe3O4 nanocomposites had higher paramagnetism and the magnetic strength reached 66.05 emu/g, which was prone to separate from solution. Graphene-Fe3O4 nanocomposites could further accelerate OFX degradation compared to sole Fe3O4. When graphene content was 18 wt%, graphene-Fe3O4 nanocomposites exhibited the highest catalytic activity, and the removal efficiency of OFX enhanced from 65.0% (PDP alone) to 99.9%. 0.23 g/L dosage and acid solution were beneficial for OFX degradation. Higher stability of graphene-Fe3O4 nanocomposites could be maintained although four times use. Graphene-Fe3O4 nanocomposites could catalyze H2O2 and O3 to produce more ·OH. The degradation products of OFX were identified by liquid chromatography mass spectrometry (LC-MS) and ion chromatography (IC). According to the identified products and discrete Fourier transform (DFT), the degradation pathway was inferred. Further toxicity assessment of products manifested that the toxicity of oral rat 50% lethal dose (LD50) and the developmental toxicity of OFX were reduced.


Assuntos
Grafite , Nanocompostos , Poluentes Químicos da Água , Animais , Catálise , Grafite/toxicidade , Peróxido de Hidrogênio , Nanocompostos/toxicidade , Ofloxacino , Plasma , Ratos , Água , Poluentes Químicos da Água/toxicidade
18.
Int J Biol Macromol ; 167: 255-266, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33246007

RESUMO

Poly (lactic acid)/lignin nanocomposites (PLA/Lig-Np) containing cinnamaldehyde (Ci) were obtained by a combination of melt extrusion and supercritical impregnation process. In this work, Ci impregnation tests were carried out in a high-pressure cell at 40 °C for 3 h using 12 MPa and 1 MPa min-1 of depressurization rate, obtaining impregnation yields ranging from 5.7 to 10.8% w/w. Thermal, mechanical and colorimetric properties of the developed films were affected by the incorporation of lignin nanoparticles and the active compound, obtaining biodegradable plastic materials with a strong UV-light barrier property compared to PLA films. In addition, disintegrability tests under composting conditions confirmed the biodegradable character of nanocomposites developed. On day 23, a disintegration percentage greater than 90% was determined for all bionanocomposites. Finally, to establish the possible toxicity effect of the nanocomposites obtained, studies in vivo were performed in normal rats. Toxicity studies showed normal blood parameters after a single dose of nanocomposites. PLA/Ci/Lig-Np bionanocomposite films could be potentially applied to design biodegradable UV-light barrier materials for food packaging and biomedical applications.


Assuntos
Acroleína/análogos & derivados , Fenômenos Químicos , Lignina/química , Nanocompostos/química , Poliésteres/química , Acroleína/química , Varredura Diferencial de Calorimetria , Técnicas de Química Sintética , Fenômenos Mecânicos , Nanocompostos/toxicidade , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Food Chem ; 342: 128385, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33097331

RESUMO

Graphene-based nanocomposites with superior antibacterial activity are highly sought after by the food packaging industries. Here, we report for the first time a method that utilizes soluble starch biopolymer as a functionalizing and reducing agent for the preparation of starch-reduced graphene oxide (SRGO), whereby polyiodide binds to the helical structures of amylose units of the starch (chromophore) to form a SRGO-polyiodide nanocomposite (SRGO-PI NC). UV-visible spectroscopy, X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and energy-dispersive spectroscopy confirmed the presence of polyiodide in SRGO. SRGO-PI NC exhibited good antibacterial activities against pathogenic Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) microbes with minimum inhibitory concentrations (MICs) and minimum bactericidal concentration (MBC) values (as determined by a broth-dilution method) of 2.5 and 5 mg/ml, respectively, for both E. coli and S. aureus. PrestoBlue viability assays showed half-maximal inhibitory concentration (IC50) values of 0.45 and 0.41 mg/ml for E. coli and S. aureus, respectively. Time-kill kinetic and live/dead bacterial viability assays revealed the antimicrobial activities of SRGO-PI NC against both E. coli and S. aureus. The study provides new insights regarding the utilization of graphene-polyiodide NCs as high-efficacy antibacterial starch-based nanomaterials for food packaging applications.


Assuntos
Antibacterianos/farmacologia , Embalagem de Alimentos/métodos , Grafite/química , Iodetos/química , Nanocompostos/química , Amido/química , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanocompostos/toxicidade , Staphylococcus aureus/efeitos dos fármacos
20.
J Mater Chem B ; 8(46): 10527-10539, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33179706

RESUMO

Nanoparticle induced hyperthermia has been considered as a promising approach for cancer treatment for decades. The local heating ability and drug delivery potential highlight a diversified possibility in clinical application, therefore a variety of nanoparticles has been developed accordingly. However, currently, only a few of them are translated into the clinical stage indicating a 'medically underexplored nanoparticles' situation, which encourages their comprehensive biomedical exploration. This study presents a thorough biological evaluation of previous well-developed dual pH- and thermo-responsive magnetic doxorubicin-nanocarriers (MNC-DOX) in multiple cancer cell lines. The cytotoxicity of the nanocomposites has been determined by the MTT assay on primary cell lines. Histology and fluorescence microscopy imaging revealed the efficiency of cellular uptake of nanocarriers in different cell lines. The IC50 of MNC-DOX is significantly higher than that of free DOX without an alternating magnetic field (AMF), which implied the potential to lower the systemic cytotoxicity in clinical research. The concurrent thermo-chemotherapy generated by this platform has been successfully achieved under an AMF. Promising effective synergistic results have been demonstrated through in vitro study in multi-model cancer cell lines via both trypan blue exclusion and bioluminescence imaging methods. Furthermore, the two most used magnetic hyperthermia modalities, namely intracellular and extracellular treatments, have been compared on the same nanocarriers in all 3 cell lines, which showed that treatment after internalization is not required but preferable. These results lead to the conclusion that this dual responsive nanocarrier has extraordinary potential to serve as a novel broad-spectrum anticancer drug and worth pursuing for potential clinical applications.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Nanopartículas de Magnetita/química , Nanocompostos/química , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/toxicidade , Ensaios de Seleção de Medicamentos Antitumorais , Fibroblastos/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Hipertermia Induzida/métodos , Campos Magnéticos , Nanopartículas de Magnetita/toxicidade , Camundongos , Nanocompostos/toxicidade , Temperatura
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