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1.
J Photochem Photobiol B ; 197: 111541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31272033

RESUMO

Here, we report the novel fabrication of ZnO nanoparticles using the Costus igneus leaf extract. Gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance (1H NMR) spectroscopy to determine the bioactive components present in the plant extract. The synthesis of Ci-ZnO NPs (C. igneus- coated zinc oxide nanoparticles) was accomplished using a cost-effective and simple technique. Ci-ZnO NPs were specified using UV-visible spectroscopy, FTIR, XRD, and TEM. Ci-ZnO NPs was authenticated by UV-Vis and exhibited a peak at 365 nm. The XRD spectra proved the crystalline character of the Ci-ZnO NPs synthesized as hexagonal wurtzite. The FTIR spectrum illustrated the presence of possible functional groups present in Ci-ZnO NPs. The TEM micrograph showed evidence of the presence of a hexagonal organization with a size of 26.55 nm typical of Ci-ZnO NPs. The α-amylase and α-glucosidase inhibition assays demonstrated antidiabetic activity of Ci-ZnO NPs (74 % and 82 %, respectively), and the DPPH [2,2-diphenyl-1-picrylhydrazyl hydrate] assay demonstrated the antioxidant activity of the nanoparticles (75%) at a concentration of 100 µg/ml. The Ci-ZnO NPs exhibited promising antibacterial and biofilm inhibition activity against the pathogenic bacteria Streptococcus mutans, Lysinibacillus fusiformis, Proteus vulgaris, and Vibrio parahaemolyticus. Additionally, the Ci-ZnO NPs showed biocompatibility with mammalian RBCs with minimum hemolytic activity (0.633 % ±â€¯0.005 %) at a concentration of 200 µg/ml.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Antibacterianos/síntese química , Antibacterianos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Costus/química , Costus/metabolismo , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Química Verde , Hemólise/efeitos dos fármacos , Humanos , Insulina/química , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
2.
J Photochem Photobiol B ; 197: 111539, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31301638

RESUMO

Treatment of burn injury is clinically challenging one, therefore several steps and noteworthy approaches have been taken to improve wound mechanisms. Citrus pectin plays a stabilizing agent to synthesis of ZnO nanoparticles (ZnO NPs). The present study is focused on ZnO loaded collagen/chitosan nanofibrous were synthesized by electrospinning method using ZnO NPs. The chemical structure, phase purity and morphological observation were investigated under spectroscopic and mircoscopic techniques and demonstrated their suitable properties as a wound healing material. In addition, that prepared nanoparticles loaded biopolymeric fibrous nanomaterial showed suitable antibacterial activity against S. aureus and E. coli bacterial pathogens and also in vitro studies was confirmed the enhanced proliferation, cell viability and biocompatibility. In vitro evaluations have been exhibited acceptable cell proliferation is observed throughout the ZnO loaded Coll/CS nanofibrous within 3 days, which was comparable to the control material. In vivo wound healing ability was monitored on the rat wound experimental model. From the in vivo observations, revealed that the loaded of ZnO NPs with Coll/CS nanofibrous can effectively quicken wound healing mechanism, expressed in the initial stage healing process. These results suggest that ZnO loaded collagen/chitosan nanofibrous is a potential candidate for wound healing applications with enhanced biological properties.


Assuntos
Queimaduras/patologia , Quitosana/química , Colágeno/química , Nanopartículas Metálicas/química , Nanofibras/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacteriemia/prevenção & controle , Queimaduras/veterinária , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Nanofibras/uso terapêutico , Nanofibras/toxicidade , Ratos , Pele/efeitos dos fármacos , Pele/patologia , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Óxido de Zinco/química
3.
J Environ Sci (China) ; 84: 97-111, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31284920

RESUMO

Heterogeneous photocatalytic reaction has been generally applied for degradation of toxic contaminants. Degradations of a compound using the same kind of catalyst that was synthesized differently are commonly found in literature. However, the reported degradation intermediates are normally inconsistent. This issue is especially important for the degradation of toxic compounds because intermediates may be more toxic than their parent compounds and understanding the reason is necessary if appropriate catalysts are to be designed. This work systematically compares the photocatalytic degradation of diuron, a toxic recalcitrant herbicide, on two forms of zinc oxide (ZnO), i.e., conventional particles with zinc- and oxygen-terminated polar surfaces as the dominating planes, and nanorods with mixed-terminated nonpolar surfaces. Experimental and theoretical results indicate that both the rate of reaction and the degradation pathway depend on the adsorption configuration of diuron onto the surface. Diuron molecules adsorb in different alignments on the two surfaces, contributing to the formation of different degradation intermediates. Both the aliphatic and aromatic sides of diuron adsorb on the polar surfaces simultaneously, leading to an attack by hydroxyl radicals from both ends. On the other hand, on the mixed-terminated surface, only the aliphatic part adsorbs and is degraded. The exposed surface is therefore the key factor controlling the degradation pathway. For diuron degradation on ZnO, a catalyst confined to mixed-terminated surfaces, i.e., ZnO nanorods, is more desirable, as it avoids the formation of intermediates with potent phytotoxicity and cytogenotoxicity.


Assuntos
Diurona/química , Fotólise , Poluentes Químicos da Água/química , Óxido de Zinco/química , Adsorção , Catálise , Cinética , Testes de Toxicidade , Vigna
4.
Ecotoxicol Environ Saf ; 182: 109396, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31276888

RESUMO

We report herein the sonochemical synthesis of a lanthanum dioxide carbonate (La2O2CO3) and zinc ferrite (ZnFe2O4)-loaded reduced graphene oxide (LZF-rGO) nanoheterostructure for ultrasound (US)-assisted degradation of methyl orange (MO) from water. The MO was chosen as a model organic dye due to its toxicological and biodegradable-resistant properties. The LZF-rGO catalyst was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results of characterizations confirmed successful synthesis of sonocatalyst. Among different removal systems, US/LZF-rGO displayed outstanding sonodegradation performance for degradation of MO. The maximum removal efficiency of 75.9% was achieved using 0.2 g/L sonocatalyst, 20 mg/L MO, and 0.71 W/cm2 US power intensity for 65 min. MO can be partially adsorbed on LZF-rGO but mostly sonodegraded by reactive radical species. The reaction conditions were optimized by investigating the effect of key operating parameters, including the sonocatalyst dosage, initial MO concentration, US power intensity, presence of inorganic salts, and use of an enhancer, on the decolorization of MO. The degradation intermediates produced from MO during the sonocatalytic process were identified by UPLC®/MS-MS, and possible mechanism and pathway for the degradation of MO in the US/LZF-rGO system were also proposed. Reusability experiments with this sonocatalyst revealed a less than 10% drop in the degradation efficiency after four adsorption-desorption cycles.


Assuntos
Corantes/química , Grafite/química , Lantânio/química , Nanoestruturas/química , Poluentes Químicos da Água/química , Carbonatos , Catálise , Compostos Férricos , Magnetismo , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Modelos Químicos , Óxidos/química , Espectroscopia Fotoeletrônica , Água , Difração de Raios X , Zinco , Compostos de Zinco , Óxido de Zinco/química
5.
Int J Nanomedicine ; 14: 3583-3600, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190813

RESUMO

Purpose: This study aimed to decorate the surface of TiO2 nanotubes (TiO2 NTs) grown on medical grade Ti-6Al-4V alloy with an antimicrobial layer of nano zinc oxide particles (nZnO) and then determine if the antimicrobial properties were maintained with a final layer of nano-hydroxyapatite (HA) on the composite. Methods: The additions of nZnO were attempted at three different annealing temperatures: 350, 450 and 550 °C. Of these temperatures, 350°C provided the most uniform and nanoporous coating and was selected for antimicrobial testing. Results: The LIVE/DEAD assay showed that ZnCl2 and nZnO alone were >90% biocidal to the attached bacteria, and nZnO as a coating on the nanotubes resulted in around 70% biocidal activity. The lactate production assay agreed with the LIVE/DEAD assay. The concentrations of lactate produced by the attached bacteria on the surface of nZnO-coated TiO2 NTs and ZnO/HA-coated TiO2 NTs were 0.13±0.03 mM and 0.37±0.1 mM, respectively, which was significantly lower than that produced by the bacteria on TiO2 NTs alone, 1.09±0.30 mM (Kruskal-Wallis, P<0.05, n=6). These biochemical measurements were correlated with electron micrographs of cell morphology and cell coverage on the coatings. Conclusion: nZnO on TiO2 NTs was a stable and antimicrobial coating, and most of the biocidal properties remained in the presence of nano-HA on the coating.


Assuntos
Anti-Infecciosos/farmacologia , Materiais Revestidos Biocompatíveis/química , Durapatita/química , Nanotubos/química , Staphylococcus aureus/efeitos dos fármacos , Titânio/química , Óxido de Zinco/química , Zinco/farmacologia , Anti-Infecciosos/química , Preparações de Ação Retardada/química , Diálise , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Nanopartículas/química , Nanopartículas/ultraestrutura , Nanotubos/ultraestrutura , Propriedades de Superfície
6.
Anal Chim Acta ; 1073: 62-71, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31146837

RESUMO

In this study, silver nanostructures decorated magnetic nanoparticles for surface-enhanced Raman scattering (SERS) measurements were prepared via heat induced catalytic activity of ZnO nanostructures. The ZnO/Fe3O4 composite was first prepared by dispersing pre-formed magnetic nanoparticles into alkaline zinc nitrate solutions. After annealing of the precipitates, the formed ZnO/Fe3O4 composites were successfully decorated with silver nanostructures by dispersing the composites into silver nitrate/ethylene glycol solution at 95 °C in water bath. To find the optimal condition when preparing Ag/ZnO/Fe3O4 composites for SERS measurements, factors such as reaction time and concentration of silver nitrate were studied. Results indicated that the formation of silver nanoparticles (AgNPs) on ZnO/Fe3O4 was significantly improved with the assistance of ZnO. The concentration of silver nitrate and reaction time affected the morphologies and sizes of the formed composites and optimal condition in preparation of the composites for SERS measurement was found using 100 mM of silver nitrate with a reaction time of 20 min. Under optimized conditions, the obtained SERS intensities were highly reproducible. The substrates were applied for quantitative analysis of uric acid in aqueous solution and a linear response for concentrations up to 10 µM was obtained. Successful application of these prepared composites to determine uric acid in urine sample without any pretreatment of the urine sample was done.


Assuntos
Óxido Ferroso-Férrico/química , Nanopartículas de Magnetita/química , Nanopartículas Metálicas/química , Prata/química , Ácido Úrico/análise , Óxido de Zinco/química , Tamanho da Partícula , Análise Espectral Raman , Propriedades de Superfície
7.
Environ Sci Pollut Res Int ; 26(23): 24062-24074, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31228065

RESUMO

Polyvinyl alcohol (PVA) filled with different kinds of ZnO whisker was prepared by chemical cross-linking reaction. It was found that the ZnO whiskers dispersed uniformly after being modified by 3-aminopropyltriethoxysilane (APTES). The PVA/tetrapod-shaped ZnO (PVA/tetra-ZnO) composites showed better adsorption performance than other kinds of PVA/ZnO composites. The framework-supported pore-channel structure was beneficial for the transmission and adsorption of heavy metal ions, and the formation of "brush" pore-channel of PVA/tetra-ZnO composites can effectively retain and capture the heavy metal ions. The PVA/tetra-ZnO composites presented well adsorption on Pb(II), Cd(II), and Cr(III) ions than Ni(II) and showed relatively selective removal on Pb(II) and Cr(III) ions. The adsorbed heavy metal ions presented gradient distribution with high content in the out layer and low content in the inner layer. Pb(II) adsorption capacity qe increased gradually with the increase of initial solution concentration and contact time which tended to be stable at 400 mg/L and 800 min. The maximal adsorption capacity qm obtained by nonlinear fitting reached to about 116 mg/g which was very close to the experiment data. Adsorption isotherm results indicated the monolayer adsorption process of the Langmuir model and the adsorption kinetics data fitted well to the pseudo-second-order model. The adsorption process was spontaneous and the high temperature was in favor of adsorption. The adsorption mechanism was explored as the combination of coordination and ion exchange. Besides, the PVA/tetra-ZnO composites exhibited better stress stability, thermo stability, and favorable regeneration than neat PVA.


Assuntos
Chumbo/análise , Álcool de Polivinil/química , Poluentes Químicos da Água/análise , Adsorção , Concentração de Íons de Hidrogênio , Íons/química , Cinética , Chumbo/química , Metais Pesados , Poluentes Químicos da Água/química , Óxido de Zinco/química
8.
Environ Sci Pollut Res Int ; 26(22): 23119-23128, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31183760

RESUMO

With the widespread use of metal oxide nanoparticles (MNPs), agricultural soil is gradually becoming a primary sink for MNPs. The effect of these nanoparticles on the fate and the toxicity of co-existing heavy metals is largely unknown. In this paper, pot experiments were conducted to evaluate the impact of ZnO nanoparticles (ZnO-NPs) on Cd toxicity and bioaccumulation in a soil-rice system. Different amounts of ZnO-NPs were added to three different levels of Cd-contaminated paddy soil (L-Cd, 1.0 mg kg-1; M-Cd, 2.5 mg kg-1; H-Cd, 5.0 mg kg-1). The results showed that the addition of ZnO-NPs significantly increased the soil pH value, and the soil pH value increased with the increase in ZnO-NP concentration. Reductions in plant height and biomass under Cd stress were recovered and increased after the addition of ZnO-NPs; the addition of ZnO-NP promoted rice biomass increased by 13~22% and 25~43% in the M-Cd and H-Cd groups, respectively, compared with that of the respective control treatment. A high concentration of ZnO-NPs could increase the concentration of bioavailable Cd in rhizosphere soil. In the L-Cd group, the Cd concentration of the rice in the L-Z500 treatment increased to 0.51 mg kg-1, exceeding the limit for acceptable Cd concentrations in rice of China (0.2 mg kg-1). This work revealed that ZnO-NPs could improve plant growth, especially in the early-growth stage, and alleviate the toxic effects of Cd. However, the addition of high-concentration (500 mg kg-1) ZnO-NPs in the lower Cd pollution soil could significantly facilitate the accumulation of Cd by Oryza sativa L.


Assuntos
Cádmio/análise , Nanopartículas Metálicas/análise , Metais Pesados/análise , Oryza/crescimento & desenvolvimento , Poluentes do Solo/análise , Agricultura , Biomassa , China , Nanopartículas Metálicas/química , Metais Pesados/química , Óxido de Zinco/química
9.
Environ Sci Pollut Res Int ; 26(22): 22450-22463, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31161548

RESUMO

Zinc oxide (ZnO) nanoparticles are commonly used in sunscreens for their UV-filtering properties. Their growing use can lead to their release into ecosystems, raising question about their toxicity. Effects of these engineered nanomaterials (ENMs) on cyanobacteria, which are important primary producers involved in many biogeochemical cycles, are unknown. In this study, we investigated by several complementary approaches the toxicological effects of two marketed ZnO-ENMs (coated and uncoated) on the model cyanobacteria Synechococcus elongatus PCC 7942. It was shown that despite the rapid adsorption of ENMs on cell surface, toxicity is mainly due to labile Zn released by ENMs. Zn dissipates cell membrane potential necessary for both photosynthesis and respiration, and induces oxidative stress leading to lipid peroxidation and DNA damages. It leads to global downregulation of photosystems, oxidative phosphorylation, and transcription/translation machineries. This also translates into significant decrease of intracellular ATP content and cell growth inhibition. However, there is no major loss of pigments and even rather an increase in exposed cells compared to controls. A proposed way to reduce the environmental impact of Zn would be the improvement of the coating stability to prevent solubility of ZnO-ENMs.


Assuntos
Cianobactérias/efeitos dos fármacos , Nanopartículas/toxicidade , Synechococcus/química , Óxido de Zinco/química , Adsorção , Cianobactérias/química , Dano ao DNA , Ecossistema , Estresse Oxidativo , Fotossíntese , Protetores Solares/química , Óxido de Zinco/toxicidade
10.
Ultrason Sonochem ; 55: 117-124, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31084785

RESUMO

The aim of the present investigation was the combination of ZnO nanostructures with nano-cellulose (NC) for the efficient degradation of tetracycline (TC) antibiotic under ultrasonic irradiation. The removal efficiency of 12.8% was obtained by the sole use of ultrasound (US), while the removal efficiency increased up to 70% by the US/ZnO treatment process. Due to the integration of ZnO nanostructures with NC, the removal efficiency of 87.6% was obtained within 45 min. The removal efficiency substantially decreased in the presence of tert-butyl alcohol (more than 25% reduction), indicating that radOH-mediation oxidation is responsible for the degradation of TC molecules. Peroxymonosulfate (PMS) led to the most enhancing effect on the removal of TC among percarbonate, persulfate and periodate ions. The addition of PMS caused the degradation efficiency of 96.4% within the short contact time of 15 min. The bio-toxicity examination on the basis of inhibition test conducted on activated sludge revealed diminishing the oxygen consumption inhibition percent [IOUR (%)] from 33.6 to 22.1% during the US/ZnO/NC process. Consequently, the utilization of the US/ZnO/NC process can convert TC molecules to less toxic compounds. However, longer reaction time is required for complete conversion into non-toxic substances.


Assuntos
Celulose/química , Nanocompostos/química , Tetraciclina/química , Tetraciclina/isolamento & purificação , Ondas Ultrassônicas , Óxido de Zinco/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Catálise , Oxidantes/química , Peróxidos/química , Água/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
11.
Ultrason Sonochem ; 55: 44-56, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31084790

RESUMO

This study focuses on the facile preparation of ZnO-biochar (ZnO-BC) nanocomposite prepared by the hydrothermal approach as an efficient sonocatalyst for degradation and mineralization of gemifloxacin (GMF). Morphological and textural characteristics of bare biochar (BC), ZnO nanorods (ZnO NRs) and ZnO-BC nanocomposite were investigated using TEM, SEM and BET analyses. Moreover, XRD, FTIR, EDX and UV-vis DRS analyses were performed to study the crystalline structure, functional groups, elemental composition and optical properties of the samples, respectively. ZnO-BC nanocomposite showed better sonocatalytic performance than BC and ZnO NRs owing to its huge surface area, narrow band gap and enhanced sonoluminescence phenomenon. These properties led to the synergetic ability of ultrasonic irradiation and catalytic activity of ZnO-BC to generate reactive species and subsequent radical reactions. In addition, the effect of the addition of various gases and scavengers on the removal of GMF was evaluated. The GC-MS analysis was used to verify the generation of some intermediates and a possible pathway was proposed accordingly. 83.7% COD removal efficiency was observed within 90 min treatment confirming efficient mineralization of GMF solution. The phytotoxicity test was carried out using Lemna minor and the results proved that after the treatment process, a considerable toxicity removal of the GMF solution had occured.


Assuntos
Araceae/efeitos dos fármacos , Carvão Vegetal/química , Gemifloxacina/química , Nanotubos , Ondas Ultrassônicas , Óxido de Zinco/química , Óxido de Zinco/toxicidade , Catálise , Concentração de Íons de Hidrogênio , Temperatura Ambiente
12.
Ultrason Sonochem ; 55: 57-66, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31084791

RESUMO

The synthesis of nanoparticles often result in the generation of harmful chemical pollutants. As such, many researchers have focused on developing green processes, which include the biosynthesis. In this research, ZnO nanoparticles were prepared using the leaf extract of whortleberry (Vaccinium arctostaphylos L.) via a simple ultrasonic-assisted method. The morphology, crystal size and structure, surface, thermal, and optical properties of the bio-mediated ZnO sample (ZnOext) were analyzed and compared with that produced without incorporating the extract (ZnOchem). The ZnO samples were evaluated for their antidiabetic, antibacterial, as well as their sono- and photo-catalytic performances. Initially, the samples were intraperitoneal injected to alloxan-diabetic rats to examine their treatment efficiency in terms of effects on fasting blood glucose, insulin, cholesterol, high-density lipoprotein, and total triglyceride levels. The ZnOext showed significantly higher efficiency for improving the health status of alloxan-diabetic rats in contrast with other tested treatments, vis. ZnOchem, insulin, and only leaf extract. In addition, both the ZnO samples were assessed against gram-negative and gram-positive bacteria and through sono- and photo-catalytic processes for removing rhodamine B, respectively. The results of this study indicated that not only the ZnOext sample was pollution free, it also exhibited higher potentials for treating diabetic rats, bacterial decontamination, and also oxidative removal of organic compounds under the influences of ultrasound and UV irradiations when compared with ZnOchem sample.


Assuntos
Nanopartículas/química , Extratos Vegetais/química , Folhas de Planta/química , Ondas Ultrassônicas , Vaccinium/química , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Técnicas de Química Sintética , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Oxirredução/efeitos dos fármacos
13.
IET Nanobiotechnol ; 13(2): 150-159, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31051445

RESUMO

This investigation has for the first time utilised environmental resource Prunus cerasifera seed extract phytochemicals for the green synthesis of carpogenic ZnO nanoparticles (NPs). Spherical morphology and size range of 56.57-107.70 nm at variable calcination temperatures without the use of any external reducing agent was obtained. The synthesised NPs exhibited hexagonal wurtzite geometry with an average crystal size 5.62 nm and a band gap of 3.4 eV. Carpogenic NPs were investigated for optical, compositional, morphological, and phytochemical make up via ultraviolet spectroscopy (UV-Vis), Fourier transform infrared analysis, X-ray powder diffraction, scanning electron microscopy, and gas chromatography and mass spectrometry. Carpogenic NPs degraded methyl red up to 83% with pseudo-first-order degradation kinetics (R2 = 0.88) in 18 min signifying their remediation role in environment in conformity with all principles of green chemistry. Photocatalytic assays were performed in direct solar irradiance. Nine pathogens of biomedical and agricultural significance having multi-drug resistance were inhibited in vitro via the Kirby-Bauer disc diffusion assay. The enhanced photocatalytic and antimicrobial inhibition not only makes carpogenic ZnO NPs a future photo-degradative candidate for environmental remediation but also a nanofertiliser, nanofungicide, and nanobactericide synthesised via bioinspired, biomimetic, green, and unprecedented route.


Assuntos
Anti-Infecciosos/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Anti-Infecciosos/farmacologia , Compostos Azo/química , Compostos Azo/metabolismo , Bactérias/efeitos dos fármacos , Química Verde , Tamanho da Partícula , Extratos Vegetais/farmacologia , Prunus domestica/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Óxido de Zinco/farmacologia
14.
IET Nanobiotechnol ; 13(2): 170-177, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31051447

RESUMO

Malaria is a dangerous disease affecting humans and animals in tropical and subtropical areas worldwide. According to recent estimates, 3.2 billion people are at risk of malaria. Many drugs are in practices to control this disease and their vectors. Eco-friendly control tools are needed to fight vectors of this important disease. Nanotechnology is playing a key role in the fight against many public health emergencies. In the present study, Lagenaria siceraria aqueous peel extract was used to prepare zinc oxide nanoparticles (ZnO NPs), then tested on Anopheles stephensi eggs, larvae and pupae. The L. siceraria-synthesised ZnO NPs were characterized additionally by FTIR, AFM, XRD, UV-Vis spectroscopy, EDX, and SEM spectroscopy The ovicidal, larvicidal, pupicidal and repellent activities of L. siceraria and green-synthesised ZnO NPs were analysed on A. stephensi. The potential mechanism of action of ZnO NPs was studied investigating the changes in various enzyme activities in A. stephensi IV instar larvae. Furthermore, the smoke toxicity of L. siceraria-based cones against A. stephensi evoked higher mortality if compared with the control. Overall, the present study concluded that L. siceraria peel extract and its mediated green synthesised ZnO NPs represent a valuable green option to manage against malaria vectors.


Assuntos
Anopheles/efeitos dos fármacos , Cucurbitaceae/química , Inseticidas/farmacologia , Nanopartículas Metálicas/química , Mosquitos Vetores/efeitos dos fármacos , Óxido de Zinco/farmacologia , Animais , Química Verde , Inseticidas/química , Larva/efeitos dos fármacos , Malária/prevenção & controle , Malária/transmissão , Controle de Mosquitos/métodos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Óxido de Zinco/química
15.
Carbohydr Polym ; 216: 376-384, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31047080

RESUMO

There is an increasing interest toward biodegradable active packaging because of consumer demand and environmental concerns. Despite this interest, poor thermal, mechanical, and water barrier properties of biodegradable polymers such as gelatin limit their application in food packaging. In this study, to prevail these limitations, the gelatin-based nanocomposite containing chitosan nanofiber (CHNF) and ZnO nanoparticles (ZnONPs) were fabricated and characterized by FTIR, SEM, and DSC analyses. The results showed the appropriate interactions between gelatin matrix, CHNF and ZnONPs due to their good compatibility. Additionally, the nanocomposite showed high mechanical and water barrier properties due to its high dense and less permeable structure. The incorporation of CHNF compensated the negative effect of ZnONPs on the color properties of gelatin film. In addition, the synergistic effect between CHNF and ZnONPs improved the antibacterial activity of nanocomposite. In conclusion, the fabricated bio nanocomposite indicated considerable potential for food packaging.


Assuntos
Antibacterianos/farmacologia , Quitosana/química , Gelatina/química , Nanopartículas Metálicas/química , Nanocompostos/química , Óxido de Zinco/farmacologia , Antibacterianos/química , Módulo de Elasticidade , Escherichia coli/efeitos dos fármacos , Embalagem de Alimentos , Membranas Artificiais , Testes de Sensibilidade Microbiana , Nanofibras/química , Permeabilidade , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Vapor , Resistência à Tração , Água/química , Óxido de Zinco/química
16.
Chemosphere ; 229: 206-213, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31078877

RESUMO

The release of nano-zinc oxide (nano-ZnO) into the environment may lead to unpredictable risks, thus it is necessary to study its potential harm to organisms. In this study, zebrafish exposed to nano-ZnO were analyzed through cDNA microarrays to provide insight into the toxic effect of nano-ZnO on aquatic organisms at the molecular level. Results found that nano-ZnO inhibited the normal growth and development of zebrafish and other life activities by affecting the process of cell cycle. The nano-ZnO inhibited the expression of the cyclins (Cycs), cyclin-dependent kinases (CDK) and the minichromosome maintenance (MCM), making the activation of Cyc/CDK complexs (CycD/CDK4, 6; CycE/CDK2; CycA/CDK2) and MCM fail and resulting in DNA replication disorder in different periods (G1, M and G2 phase). Therefore, the normal activities of individual organism such as cell division, differentiation and proliferation and the functions of DNA binding and intracellular transfer were disturbed. These findings contribute to our understanding of the toxicity of ZnO NPs to aquatic organisms, and also provide an evaluation basis for assessing the environmental impact of nano materials.


Assuntos
Ciclo Celular/efeitos dos fármacos , Nanoestruturas/toxicidade , Peixe-Zebra , Óxido de Zinco/química , Óxido de Zinco/toxicidade , Animais , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
17.
Ecotoxicol Environ Saf ; 180: 259-268, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31096129

RESUMO

Our study determined the toxic effects of zinc oxide (ZnO) particles with different diameters on dopaminergic (DA) neurons, the role of ubiquitin C-terminal hydrolase L1 (UCH-L1) for ZnO particles-induced neurotoxicity, and corresponding molecular mechanisms. We constructed an in vitro cell injury model for DA neurons to analyze the cytotoxicity of ZnO particles using SH-SY5Y cells. Following cell viability assays and flow cytometry, we found that the cytotoxicity of ZnO particles was affected by particle size, time, and dose of exposure. For example, the toxicity of ZnO particles with 50 nm or 100 nm diameter was stronger than that of ZnO particles with 1000 nm diameter. Furthermore, ZnO particles exposure resulted in a significant decrease in UCH-L1 expression in SH-SY5Y; whereas UCH-L1 overexpression led to a significant increase in cell viability and a sharp decrease in ROS level. Western blotting and adenovirus transfection found that exposure to ZnO particles with different diameters all activate the NF-κB signaling in SH-SY5Y cells; whereas UCH-L1 over-expression resulted in increased levels of IκBα, an endogenous inhibitor of NF-κB signaling pathway. ZnO particles with different diameters all induced cytotoxicity in DA neurons, which may be related to the free Zn2+ in the suspension. Regarding the neurotoxic effect of ZnO particles, UCH-L1 protects against and/or alleviates neuronal damage, possibly by deubiquitination of the endogenous inhibitor, IκBα, which leads to activation of NF-κB signaling. Therefore, one possible mechanism for ZnO particle-induced neurotoxicity may be mediated via the down-regulation of UCH-L1 expression in DA cells.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/metabolismo , Ubiquitina Tiolesterase/metabolismo , Óxido de Zinco/toxicidade , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Regulação para Baixo , Humanos , Inibidor de NF-kappaB alfa/genética , Tamanho da Partícula , Transdução de Sinais/efeitos dos fármacos , Propriedades de Superfície , Óxido de Zinco/química
18.
Talanta ; 200: 378-386, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31036199

RESUMO

Zinc oxide (ZnO) based nanostructures owing unique physical properties - high photoluminescence, biocompatibility and other characteristics, therefore, they attract attention as building blocks suitable for biosensor development. In this research as a target we have used human leukemic cell line IM9 (IM9). IM9 was derived from the patient with a multiple myeloma and expressed cluster of differentiation proteins СD19 on the surface of 85-95% here investigated cancer cells. As a control sample healthy human's peripheral blood mononuclear cells (PBMC) were used and the expression of CD19 protein was found only in 5-9% of these cells. Two types of antibodies labeled by fluorescein isothiocyanate (FITC) were used for the labeling of human leukemic cells: FITC-conjugated mouse antibodies against Human CD19 protein (anti-CD19-FITC*) and FITC-conjugated mouse antibodies against Human IgG1 protein (anti-IgG1-FITC*). In order to demonstrate the applicability of zinc oxide nanorods (ZnO-NRs) based platforms three types of ZnO-NRs-based structures were investigated: (i) ZnO-NRs modified by anti-CD19-FITC*; (ii) ZnO-NRs modified by IM9 cells, which were pre-incubated with anti-CD19-FITC*; (iii) ZnO-NRs modified by PBMC cells, which were pre-incubated with anti-CD19-FITC*. It was demonstrated that IM9 cells after specific interaction with anti-CD19-FITC* bind to ZnO-NRs (ZnO-NRs/IM9 +anti-CD19-FITC*) and photoluminescence based signal significantly increase in comparison with that observed in control samples, which contained PBMC cells incubated with anti-CD19-FITC* (ZnO-NRs/PBMC+anti-CD19-FITC*). The photoluminescence results are in good correlation with the data obtained by flow cytometry. This study illustrate that ZnO-NRs exhibit a photoluminescence signal suitable for the determination of anti-CD19-FITC* labeled IM9 cell line at concentrations - from 10 till 500 cells adsorbed per 1 mm2 of ZnO-NRs platform.


Assuntos
Linfócitos B/patologia , Separação Celular , Imunoensaio/métodos , Leucemia/patologia , Nanotubos/química , Óxido de Zinco/química , Biomarcadores/sangue , Células Cultivadas , Citometria de Fluxo , Humanos , Óxido de Zinco/síntese química
19.
Chemosphere ; 229: 1-7, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31063875

RESUMO

Zinc oxide-coated zeolite (ZOCZ) and zinc oxide (ZnO) were compared in terms of their effectiveness in removing Staphylococcus aureus (S. aureus) from nutrient broth and phosphate-buffered saline (PBS) solution. ZOCZ was found to be extremely efficient in removing S. aureus. ZnO initially was much less effective. Photographs of removal S. aureus from PBS solution with ZOCZ confirmed that a multilayer of S. aureus cells forms on the surface of ZOCZ particles. The comparison of the images of confocal laser scanning microscope and inverted contrast fluorescence microscope further proved that a multilayer of S. aureus cells formed on the surface of ZnO-30N-zeolite. The FESEM images showed that the cell membranes of S. aureus attached to the surface of ZnO-30N-zeolite collapsed. Energy Dispersive X-Ray Spectrum and the atomic absorption spectroscopic analysis confirmed that zinc ions penetrate into S. aureus cells, causing their death. The dead cells were easily removed, allowing ZOCZ to be reused.


Assuntos
Staphylococcus aureus/efeitos dos fármacos , Zeolitas/química , Óxido de Zinco/química , Adsorção , Fármacos Dermatológicos
20.
Carbohydr Polym ; 217: 15-25, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079671

RESUMO

A bifunctional interfacial layer was introduced onto the surface of cotton fabric which not only enhanced the interfacial bonding between Ag@ZnO and organic substrates but also improved the photocatalytic performance simultaneously. In detail, a modified cotton fabric (denoted as Cot-g-Si/Ag@ZnO) was fabricated through radiation-induced graft polymerization of γ-methacryloxypropyl trimethoxysilane and followed the in-situ formation of ZnO and loading of Ag nanoparticles simultaneously. Owing to ZnOSi between the graft chains and Ag@ZnO photocatalyst, the charge carrier concentration increased and Ag was prevented from oxidizing through the partial separation from ZnO, leading to enhanced near-field amplitudes of the localized surface plasmon resonance. Cot-g-Si/Ag@ZnO also exhibited excellent photocorrosion resistance, photostability and laundering durability. Its photocatalytic activity was fully maintained after several photodegradation cycles; moreover, after laundering durability test, the photocatalytic activity was improved compared with the newly prepared one. Credible mechanism for the photocatalytic activity of Cot-g-Si/Ag@ZnO under sunlight irradiation is proposed.


Assuntos
Antibacterianos/farmacologia , Fibra de Algodão , Nanopartículas Metálicas/química , Siloxanas/farmacologia , Prata/química , Óxido de Zinco/farmacologia , Antibacterianos/química , Antibacterianos/efeitos da radiação , Catálise , Escherichia coli/efeitos dos fármacos , Gossypium/química , Luz , Nanopartículas Metálicas/efeitos da radiação , Azul de Metileno/efeitos da radiação , Fotólise , Rodaminas/efeitos da radiação , Siloxanas/química , Siloxanas/efeitos da radiação , Prata/efeitos da radiação , Staphylococcus aureus/efeitos dos fármacos , Óxido de Zinco/química , Óxido de Zinco/efeitos da radiação
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