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1.
Int J Nanomedicine ; 15: 5097-5111, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764939

RESUMO

Introduction: In this in-vitro study, we designed a 3D printed composite of zinc oxide (ZnO) nanoparticles (NPs) with photocatalytic activities encapsulated within hydrogel (alginate) constructs, for antibacterial purposes applicable towards wound healing. We primarily sought to confirm the mechanical properties and cell compatibility of these ZnO NP infused scaffolds. Methods: The antibacterial property of the ZnO NPs was confirmed by hydroxyl radical generation using ultraviolet (U.V.) photocatalysis. Titanium dioxide (TiO2), a well-known antibacterial compound, was used as a positive control (1% w/v) for the ZnO NP-based alginate constructs and their antibacterial efficacies compared. Among the ZnO group, 3D printed gels containing 0.5% and 1% w/v of ZnO were analyzed and compared with manually casted samples via SEM, swelling evaluation, and rheological analysis. Envisioning an in-vivo application for the 3D printed ZnO NP-based alginates, we studied their antibacterial properties by bacterial broth testing, cytocompatibility via live/dead assay, and moisture retention capabilities utilizing a humidity sensor. Results: 3D printed constructs revealed significantly greater pore sizes and enhanced structural stability compared to manually casted samples. For all samples, the addition of ZnO or TiO2 resulted in significantly stiffer gels in comparison with the alginate control. Bacterial resistance testing on Staphylococcus epidermidis indicated the addition of ZnO NPs to the gels decreased bacterial growth when compared to the alginate only gels. Cell viability of STO-fibroblasts was not adversely affected by the addition of ZnO NPs to the alginate gels. Furthermore, the addition of increasing doses of ZnO NPs to the alginate demonstrated increased humidity retention in gels. Discussion: The customization of 3D printed alginates containing antibacterial ZnO NPs leads to an alternative that allows accessible mobility of molecular exchange required for improving chronic wound healing. This scaffold can provide a cost-effective and durable antibacterial treatment option.


Assuntos
Alginatos/química , Alginatos/farmacologia , Hidrogéis/química , Nanopartículas/química , Cicatrização/efeitos dos fármacos , Óxido de Zinco/química , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia
2.
Small ; 16(38): e2003010, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32815251

RESUMO

Currently, mesenchymal stem cells (MSCs)-based therapies for bone regeneration and treatments have gained significant attention in clinical research. Though many chemical and physical cues which influence the osteogenic differentiation of MSCs have been explored, scaffolds combining the benefits of Zn2+ ions and unique nanostructures may become an ideal interface to enhance osteogenic and anti-infective capabilities simultaneously. In this work, motivated by the enormous advantages of Zn-based metal-organic framework-derived nanocarbons, C-ZnO nanocarbons-modified fibrous scaffolds for stem cell-based osteogenic differentiation are constructed. The modified scaffolds show enhanced expression of alkaline phosphatase, bone sialoprotein, vinculin, and a larger cell spreading area. Meanwhile, the caging of ZnO nanoparticles can allow the slow release of Zn2+ ions, which not only activate various signaling pathways to guide osteogenic differentiation but also prevent the potential bacterial infection of implantable scaffolds. Overall, this study may provide new insight for designing stem cell-based nanostructured fibrous scaffolds with simultaneously enhanced osteogenic and anti-infective capabilities.


Assuntos
Carbono/química , Células-Tronco Mesenquimais/citologia , Nanofibras/química , Osteogênese/fisiologia , Tecidos Suporte/química , Óxido de Zinco/química , Fosfatase Alcalina/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Humanos , Sialoproteína de Ligação à Integrina/metabolismo , Teste de Materiais , Células-Tronco Mesenquimais/metabolismo , Microscopia Eletrônica de Varredura , Nanofibras/ultraestrutura , Transdução de Sinais , Engenharia Tecidual , Vinculina/metabolismo
3.
Food Chem ; 332: 127375, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32622189

RESUMO

Biopolymer films based on chitosan/potato protein/linseed oil/ZnO NPs were developed to maintain the storage quality of raw meat. Results indicated that the incorporation of ZnO NPs could effectively improve the transparency and tensile strength of the films, while addition of linseed oil could make the composite film maintain good elastic property. Films blended with chitosan/potato protein/linseed oil/ZnO NPs (Fcpzl) exhibited an excellent moisture barrier capability. SEM showed that ZnO NPs could harmoniously exist in various polymers matrix. FTIR analysis demonstrated that different components were bound together by intramolecular and intermolecular interactions, among which hydrogen bonds were the main force. Raw meat samples were wrapped with different films to evaluate the preservative effect during 4 °C storage. Results indicated that Fcpzl possessed best protective effect of raw meat with excellent acceptable sensory properties during 7 days storage, which could reduce the speed of increasing pH and total bacterial counts.


Assuntos
Quitosana/química , Embalagem de Alimentos/métodos , Armazenamento de Alimentos/métodos , Óleo de Semente do Linho/química , Carne , Proteínas de Plantas/química , Óxido de Zinco/química , Qualidade dos Alimentos , Carne/microbiologia , Solanum tuberosum/química , Resistência à Tração
4.
Chemosphere ; 259: 127292, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32593007

RESUMO

A novel pie-like structure of vertically stacked ZnO-nanodisks on Cu-nanoplates interlayer is prepared for the first time by a facile synthesis. The photochemical activity of the as-prepared samples was evaluated by the degradation of Rhodamine B (RhB) under UV-light. Because of the formation of heterojunction and closely-bonded layered structure, the novel nanocomposites can restrain the recombination of charge carriers and have better collection ability of light. The photocatalytic experiments show that the composites are 258% of the catalytic activity of pure ZnO-nanodisks prepared by the same method, and the target pollutant RhB was almost completely degraded (96.5%) within only 10 mins. The novel Cu-nanoplates/ZnO-nanodisks assembled materials with greatly promoted performance are of significant interest for chemical and environmental applications.


Assuntos
Cobre/química , Nanopartículas Metálicas/química , Óxido de Zinco/química , Catálise , Nanocompostos/química , Rodaminas
5.
Chemosphere ; 259: 127414, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32599381

RESUMO

The photocatalytic degradation of simazine (SIM) was investigated using zinc oxide/graphene oxide (ZnO/GO) composite materials under visible light irradiation. The reaction kinetics was studied to optimize the reaction parameters for efficient degradation of SIM. Batch studies were performed to investigate the effects of initial reaction pH, the loading of the ZnO onto GO, and mass of catalyst on the removal of SIM from aqueous solution. A pH of 2 was determined to be the optimal reaction pH for the different ZnO-loaded GO catalysts. In addition, a mass of 40 mg of catalyst in the reaction was observed to be the most effective for the catalysts synthesized using 20 and 30 mmol of Zn2+ ions; whereas a mass of 10 mg was most effective for the ZnO/GO composite material synthesized using 10 mmol Zn2+ ions. The reaction was observed to follow a second-order kinetics for the degradation process. Furthermore, the synthesized ZnO/GO composite catalysts resulted in higher reaction rates than those observed for pure ZnO. The 30 mmol ZnO/GO composite expressed a rate of SIM degradation ten times greater than the rate observed for pure ZnO, and sixty-two times greater than the rate of photolysis. In addition, the catalyst cycling exhibited a constant photocatalytic activity for the ZnO/GO composite over three reaction cycles without the need of a conditioning cycle.


Assuntos
Grafite/química , Simazina/química , Óxido de Zinco/química , Catálise , Luz , Fotólise
6.
Nat Commun ; 11(1): 2405, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415064

RESUMO

Fiber-based electronics enabling lightweight and mechanically flexible/stretchable functions are desirable for numerous e-textile/e-skin optoelectronic applications. These wearable devices require low-cost manufacturing, high reliability, multifunctionality and long-term stability. Here, we report the preparation of representative classes of 3D-inorganic nanofiber network (FN) films by a blow-spinning technique, including semiconducting indium-gallium-zinc oxide (IGZO) and copper oxide, as well as conducting indium-tin oxide and copper metal. Specifically, thin-film transistors based on IGZO FN exhibit negligible performance degradation after one thousand bending cycles and exceptional room-temperature gas sensing performance. Owing to their great stretchability, these metal oxide FNs can be laminated/embedded on/into elastomers, yielding multifunctional single-sensing resistors as well as fully monolithically integrated e-skin devices. These can detect and differentiate multiple stimuli including analytes, light, strain, pressure, temperature, humidity, body movement, and respiratory functions. All of these FN-based devices exhibit excellent sensitivity, response time, and detection limits, making them promising candidates for versatile wearable electronics.


Assuntos
Nanopartículas Metálicas/química , Nanofibras/química , Dispositivos Eletrônicos Vestíveis , Consumo de Bebidas Alcoólicas , Técnicas Biossensoriais , Testes Respiratórios , Cobre/química , Elastômeros , Etanol/análise , Análise de Elementos Finitos , Gálio/química , Humanos , Índio/química , Teste de Materiais , Movimento (Física) , Poliestirenos/química , Semicondutores , Espectrofotometria Ultravioleta , Temperatura , Têxteis , Óxido de Zinco/química
7.
Zhongguo Zhong Yao Za Zhi ; 45(2): 352-360, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32237318

RESUMO

In this paper, some quality problems of mineral medicine Calamina and calcined Calamina have been discussed after determination and analysis of the quality parameters of a large number of market samples, and the countermeasures are put forward. According to the XRD results, as well as the results of tests included in Chinese Pharmacopoeia(2015 edition), the authenticity of Calamina and calcined Calamina samples were identified. The content of zinc oxide in samples were determined by the method of determination in Chinese Pharmacopoeia. Individually, inductively coupled plasma mass spectrometry(ICP-MS), inductively coupled plasma atomic emission spectrometry(ICP-AES) and atomic fluorescence spectrometry(AFS) methods were used for the determination of impurity elements and harmful elements in Calamina and calcined Calamina samples. Four kinds of impurity elements of magnesium(Mg), iron(Fe), aluminum(Al), calcium(Ca) and five harmful elements such as lead(Pb), cadmium(Cd), arsenic(As), copper(Cu), mercury(Hg) were measured. The study showed that: ① Fake Calamina products on the market were overflowing; ② The mineral origin of the mainstream Calamina in the market is inconsistent with that stipulated in Chinese Pharmacopoeia(2015 edition); ③ The contents of harmful elements Pb and Cd in Calamina and calcined Calamina are generally higher, while the contents of harmful elements As and Cu in some inferior Calaminae are higher; ④ Parts of calcined Calamina were improperly or inadequately processed. In view of these quality problems, the countermeasures are put forward as follows: ① It is suggested that hydrozincite should be approved as the mineral source of Calamina, and be included by Chinese Pharmacopoeia; ② Strengthen the research on the specificity of Calamina identification methods to improve the quality control level; ③ Strengthen the research on the processing of Calamina, and formulate the limit standards for the content of Pb and Cd in Calamina; ④ Carry out research on the artificial synthesis of Calamina and calcined Calamina, in order to cope with the current shortage of Calamina resources and ensure the sustainable development of Calamina medicinal materials.


Assuntos
Medicamentos de Ervas Chinesas/química , Compostos Férricos/química , Controle de Qualidade , Óxido de Zinco/química , Arsênico , Cádmio , Cobre , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/normas , Compostos Férricos/normas , Ferro , Chumbo , Medicina Tradicional Chinesa , Mercúrio , Minerais , Oligoelementos/análise , Óxido de Zinco/normas
8.
Ecotoxicol Environ Saf ; 196: 110532, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32247243

RESUMO

A major uptake route of nanoparticles (NPs) occurs via the gastrointestinal (GI) tract. When GI tract cells are exposed, NPs cytotoxic effects are observed that subsequently adversely affect the GI tract morphology and have consequences for the whole organism. The aim of this study was to understand the mechanism of effects caused by ZnO-NPs compared to Zn ions on the earthworm Eisenia andrei. The following aspects of individually exposed earthworms were investigated: 1) qualitative structural alterations in the gut epithelium and chloragogen cells of the GI tract, 2) quantitative changes within chloragogen tissues after 48 h of exposure (using morphometric analysis), and 3) the ADP/ATP ratio in homogenized tissue of the whole organism after 21 days of exposure to contaminated soil (contamination phase) followed by 14 days of elimination in clean soil (decontamination phase) to identify possible recovery. Both ZnO-NPs and Zn ions adversely affect the gut epithelium and chloragogen tissue of earthworms after 48 h of exposure to contaminated soil. Morphometric measurements revealed that the proportions of debris vesicles in the chloragocytes were significantly lower in worms exposed to ZnO-NPs than in worms exposed to Zn ions. Moreover, numerous spherite granules were observed in the chloragocytes of ionic Zn-treated worms, but not the ZnO-NPs-treated worms, suggesting differential regulation of these Zn forms. The Zn cytotoxic effect was not reflected in ADP/ATP ratio measurements. Our study provides new insights into nano-specific effects that are distinctive from ion regulation inside the GI tract and furthers our understanding of the relationship between effects at the cellular and whole-body levels.


Assuntos
Trato Gastrointestinal/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Óxido de Zinco/toxicidade , Animais , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/patologia , Nanopartículas Metálicas/química , Oligoquetos/metabolismo , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Zinco/metabolismo , Zinco/toxicidade , Óxido de Zinco/química , Óxido de Zinco/metabolismo
9.
Food Chem ; 322: 126778, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32305007

RESUMO

Zearalenone (ZEN) is highly toxic to humans, and therefore, development of sensitive and effective methods for ZEN quantification in cereal crops is particularly important. Here, an innovative photoelectrochemical (PEC) aptasensor based on simply in-situ conjugated composites of zinc oxide-nitrogen doped graphene quantum dots (ZnO-NGQDs) was constructed. On addition of NGQDs, the composites displayed higher PEC signal with 8.8-fold enhancement than pure ZnO nanoparticles. A sensitive and selective PEC aptasensor was fabricated by combining the composites with ZEN aptamer, which yielded an excellent analytical performance for ZEN detection, with a wide linear range of 1.0 × 10-13-1.0 × 10-7 g mL-1 and a low detection limit of 3.3 × 10-14 g mL-1. Good recoveries were obtained using the PEC aptasensor, which were consistent with those obtained using the national standard method (HPLC-MS). Finally, ZEN in mildewing cereal crops was monitored with the PEC aptasensor, exhibiting good potential for application in cereal crops for early diagnosis.


Assuntos
Aptâmeros de Nucleotídeos/química , Grão Comestível/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Fotoquímica/métodos , Zearalenona/análise , Grão Comestível/microbiologia , Farinha/análise , Farinha/microbiologia , Grafite/química , Limite de Detecção , Óxido Nítrico/química , Pontos Quânticos , Óxido de Zinco/química
10.
Chemosphere ; 251: 126419, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32171133

RESUMO

Due to their release into the environment, zinc oxide nanoparticles (ZnO NPs) may come in contact with plants. In elevated concentrations, ZnO NPs induce reactive oxygen species (ROS) production, but the metabolism of reactive nitrogen species (RNS) and the consequent nitro-oxidative signalling has not been examined so far. In this work, Brassica napus and Brassica juncea seedlings were treated with chemically synthetized ZnO NPs (∼8 nm, 0, 25 or 100 mg/L). At low dose (25 mg/L) ZnO NP exerted a positive effect, while at elevated concentration (100 mg/L) it was toxic to both species. Additionally, B. juncea was more tolerant to ZnO NPs than B. napus. The ZnO NPs could enter the root cells due to their small (∼8 nm) size which resulted in the release of Zn2+ and subsequently increased Zn2+ content in the plant organs. ZnO NPs disturbed superoxide radical and hydrogen peroxide homeostasis and modulated ROS metabolic enzymes (NADPH oxidase, superoxide dismutase, ascorbate peroxidase) and non-enzymatic antioxidants (ascorbate and glutathione) inducing similar changes in oxidative signalling in both Brassica species. The homeostasis of RNS (nitric oxide, peroxynitrite and S-nitrosoglutathione) was also altered by ZnO NPs; however, changes in nitrosative signalling proved to be different in the examined species. Moreover, ZnO NPs triggered changes in protein carbonylation and nitration. These results suggest that ZnO NPs induce changes in nitro-oxidative signalling which may contribute to ZnO NP toxicity. Furthermore, difference in ZnO NP tolerance of Brassica species is more likely related to nitrosative than to oxidative signalling.


Assuntos
Brassica/fisiologia , Nanopartículas/toxicidade , Óxido de Zinco/toxicidade , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Brassica napus/metabolismo , Glutationa/metabolismo , Mostardeira/metabolismo , Nanopartículas/química , Oxirredução , Raízes de Plantas/metabolismo , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio/metabolismo , Plântula/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Zinco/química , Óxido de Zinco/química
11.
Ecotoxicol Environ Saf ; 194: 110415, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32151871

RESUMO

Zinc oxide Nanoparticles (ZnO NPs) are widely used as emerging materials in agricultural and food-related fields, which exists potential safety hazards to public health and environment while bringing an added level of convenience to our original life. It has been proved that ZnO NPs could be taken up by pregnant women and passed through human placental barrier. However, the toxic potential for embryo development remains largely unanswered. In this study, we discovered that ZnO NPs caused the cytotoxicity in vitro. Inhibition of free Zn2+ ions in solution by EDTA or inhibition of Zn2+ ions absorption by CaCl2 could partially eliminate ZnO NPs-mediated cell toxicity, though not redeem completely. This indicated that both nanoparticles and the release of Zn2+ ions were involved in ZnO NPs-mediated cytotoxicity. In addition, we also found that both nanoparticles and Zn2+ ion release triggered reactive oxygen species (ROS) production, which further induced cell toxicity, inflammation and apoptosis, which are mediated by NF-κB signaling cascades and the mitochondria dysfunction, respectively. Eventually, these events lead to the suppressed production and migration of cranial neural crest cells (CNCCs), which subsequently prompts the craniofacial defects in chicken embryos. The application of the antioxidant N-Acetyl-L-cysteine (NAC) rescued the ZnO NPs-induced cell toxicity and malformation of the CNCCs, which further verified our hypothesis. Our results revealed the relevant mechanism of ZnO NPs exposure-inhibited the development of CNCCs, which absolutely contribute to assess the risk of nanoparticles application.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Nanopartículas/toxicidade , Crista Neural/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Óxido de Zinco/toxicidade , Acetilcisteína/farmacologia , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Embrião de Galinha , Feminino , Células HEK293 , Humanos , Mitocôndrias/efeitos dos fármacos , NF-kappa B/metabolismo , Nanopartículas/química , Crista Neural/embriologia , Espécies Reativas de Oxigênio/metabolismo , Óxido de Zinco/química
12.
Arch Biochem Biophys ; 683: 108324, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32112740

RESUMO

Glaucoma is the leading cause of irreversible blindness in the world and trabeculectomy remains still the most commonly performed filtration surgery. Failure of trabeculectomy is due to the formation of scarring, which is associated with the increased fibroblast proliferation, activation, and collagen deposition at the site of the drainage channel with subconjunctival fibrosis. Our previous study has revealed that zinc oxide (ZnO) nanoparticles could efficiently decrease the expressions of TGF-ß1 and inhibit fibroblast-mediated collagen lattice contraction. However, the mechanism underlying ZnO nanoparticle-induced fibroblast apoptosis is still unclear. In the present study, we investigated the effect of ZnO nanoparticles on the reactive oxygen species (ROS) and mitochondrial membrane potential (Δψm) in human Tenon fibroblasts (HTFs). Moreover, we also explored the influence of ZnO nanoparticles on the expression of Caspase-3, Caspase-9, apoptotic protease-activating factor-1 (Apaf-1), fibroblast-specific protein-1 (FSP-1), collagen III, and E-cadherin. The results indicated that ZnO nanoparticles markedly inhibit HTFs viability and decrease the Δψm in a concentration-dependent pattern. Exposure of HTFs to ZnO nanoparticles could also induce the elevated Caspase-3, Caspase-9, and Apaf-1 expression, decrease the levels of FSP-1, collagen III, and E-cadherin expression, leading to HTFs apoptosis. Our results suggested that elevated ROS and activated Caspase signaling play a fundamental role in ZnO nanoparticle-induced HTFs apoptosis.


Assuntos
Apoptose , Fibroblastos/citologia , Nanopartículas Metálicas/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Óxido de Zinco/química , Antioxidantes/metabolismo , Fator Apoptótico 1 Ativador de Proteases/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Movimento Celular , Sobrevivência Celular , Humanos , Potencial da Membrana Mitocondrial , Fator de Crescimento Transformador beta1/metabolismo
13.
Int J Nanomedicine ; 15: 1-15, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32021161

RESUMO

Background: Developing an ideal wound dressing that meets the multiple demands of safe and practical, good biocompatibility, superior mechanical property and excellent antibacterial activity is highly desirable for wound healing. Bacterial cellulose (BC) is one of such promising class of biopolymers since it can control wound exudates and can provide moist environment to a wound resulting in better wound healing. However, the lack of antibacterial activity has limited its application. Methods and Results: We prepared a flexible dressing based on a bacterial cellulose membrane and then modified it by chemical crosslinking to prepare in situ synthesis of nZnO/BCM via a facile and eco-friendly approach. Scanning electron microscopy (SEM) results indicated that nZnO/BCM membranes were characterized by an ideal porous structure (pore size: 30~ 90 µm), forming a unique string-beaded morphology. The average water vapor transmission of nZnO/BCM was 2856.60 g/m2/day, which improved the moist environment of nZnO/BCM. ATR-FITR further confirmed the stepwise deposition of nano-zinc oxide. Tensile testing indicated that our nanocomposites were flexible, comfortable and resilient. Bacterial suspension assay and plate counting methods demonstrated that 5wt. % nZnO/BCM possessed excellent antibacterial activity against S.aureus and E. coli, while MTT assay demonstrated that they had no measurable cytotoxicity toward mammalian cells. Moreover, skin irritation test and histocompatibility examination supported that 5wt. % nZnO/BCM had no stimulation to skin and had acceptable biocompatibility with little infiltration of the inflammatory cells. Finally, by using a bacteria-infected (S. aureus and E. coli) murine wound model, we found that nZnO/BCM could prevent in vivo bacterial infections and promote wound healing via accelerating the re-epithelialization and wound contraction, and these membranes had no obvious toxicity toward normal tissues. Conclusion: Therefore, the constructed nZnO/BCM has great potential for biomedical applications as an efficient antibacterial wound dressing.


Assuntos
Antibacterianos/farmacologia , Celulose/metabolismo , Nanocompostos/química , Cicatrização/efeitos dos fármacos , Óxido de Zinco/farmacologia , Animais , Antibacterianos/química , Bandagens , Membrana Celular/química , Celulose/química , Escherichia coli/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Nanocompostos/toxicidade , Porosidade , Coelhos , Pele/efeitos dos fármacos , Testes Cutâneos , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Infecção dos Ferimentos/microbiologia , Infecção dos Ferimentos/terapia , Óxido de Zinco/química
14.
J Appl Microbiol ; 128(6): 1764-1775, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32027448

RESUMO

AIMS: The purpose of this study was to isolate Lactobacillus from gastrointestinal tract of healthy postweaning piglets and investigate its synergistic antimicrobial and probiotic effects with ZnO nanoparticles (nZnO). METHODS AND RESULTS: Of the 128 isolates, Lactobacillus plantarum BLPL03 was selected based on its excellent acid and bile salt tolerance properties. Lactobacillus plantarum BLPL03 was sensitive to ß-lactams, macrolides, amphenicols and cephalosporins, whereas it displayed the steady resistance to aminoglycosides, tetracyclines, quinolones and peptide antibiotics. In vitro analysis of antibacterial activities showed that L. plantarum BLPL03 inhibited the four common food-borne pathogenic bacteria including Escherichia coli O157:H7 CMCC 44828, Salmonella Typhimurium ATCC 13311, Staphylococcus aureus CMCC 26003 and Listeria monocytogenes CMCC 54007 in synergy with nZnO. Furthermore, the quantitative polymerase chain reaction test demonstrated that the combined administration of L. plantarum BLPL03 fermentation liquor (LFL) and nZnO synergistically elevated the faecal number of Bifidobacterium by 73·19-fold, and reduced the two potential enteropathogenic bacteria Enterobacteriaceae and Clostridium perfringens in mice challenged with Salm. Typhimurium. Finally, dietary supplementation with low dose of nZnO (20 mg kg-1 ) when combined with LFL administration enhanced final body weight, fur appearance and average daily gain, and decreased feed conversion ratio and diarrhoea incidence in weaned piglets. The faecal Bifidobacterium and Lactobacillus of piglets were dramatically enhanced by 81·96- and 3·15-fold, respectively, after administration of a mixture of nZnO and LFL. Meanwhile, combination of nZnO with LFL resulted in low levels of Bacteroides, Enterococcus, and Enterobacteriaceae. CONCLUSIONS: A combination of nZnO and LFL exhibits potential health-benefit properties for the control of gut microbial composition by their synergistic antimicrobial and probiotic effects. SIGNIFICANCE AND IMPACT OF THE STUDY: This study may provide a potential nutritional strategy to improve performance and gut health of animals with gut microbiota disorders caused by pathogen infections and weanling, and so on.


Assuntos
Antibacterianos/farmacologia , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/fisiologia , Probióticos/farmacologia , Óxido de Zinco/farmacologia , Animais , Antibacterianos/administração & dosagem , Suplementos Nutricionais , Sinergismo Farmacológico , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/microbiologia , Lactobacillus plantarum/efeitos dos fármacos , Camundongos , Nanopartículas/administração & dosagem , Nanopartículas/química , Probióticos/administração & dosagem , Suínos/microbiologia , Desmame , Óxido de Zinco/administração & dosagem , Óxido de Zinco/química
15.
Ecotoxicol Environ Saf ; 191: 110177, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31958627

RESUMO

Advances in large hydroponic production of leafy greens, easy adoption in urban agriculture, and large leaf surface area of many leafy greens, greatly increase their exposure to heavy metals and nanoparticles. Cadmium (Cd) and lead (Pb) are two highly toxic heavy metals, which threaten the health of humans and livestock even at trace levels. These heavy metals may be taken up by plant roots through the protein transporters used for essential minerals such as iron (Fe2+) and copper (Cu2+). Previous studies have shown that some metallic nanoparticles affect the performance of protein transporters and modify the plant uptake of co-existing heavy metal ions. This study aims to understand the role of zinc oxide nanoparticles (ZnONPs) in the uptake pattern of Cd and Pb and two key micronutrients of iron and copper in edible tissues of three leafy green species including spinach (Spinaciae oleracea), parsley (Petroselinum sativum) and cilantro (Coriandrum sativum). Pre-grown plant seedlings in soil (containing Cu and Fe) were transplanted to a hydroponic system (1/4th Hoagland solution) for 7 days as a transition, and then were exposed to four treatments in deionized water (1.0 mg L-1 Cd2++100.0 mg L-1 Pb2+, 1.0 mg L-1 Cd2++100.0 mg L-1 Pb2+ + 100 mg L-1 ZnONPs, 100 mg L-1 ZnO-ENPs and a control with no chemical exposure) for additional two weeks. At termination, shoots were gently separated from the roots, and the concentrations of Pb, Cd, Fe, Zn, and Cu in all plant tissues were quantified by inductively coupled plasma-mass spectrometry (ICP-MS). The results revealed that ZnONPs mitigated the uptake of both heavy metals in roots. The translocation of heavy metals was similar in the edible tissues of three species. The response of three leafy greens to the co-exposure of heavy metals and ZnONPs was different in Cu and Fe accumulation in edible tissues. Fe concentration in edible tissues in the co-exposed plants was increased in spinach (+10%) and cilantro (+9%) but decreased in parsley (-8%) compared to controls, while the Cu level in edible tissues increased in all three species following the order of cilantro (+8%)> spinach (+4%)> parsley (+1.5%).


Assuntos
Produtos Agrícolas/metabolismo , Metais Pesados/metabolismo , Nutrientes/metabolismo , Poluentes Químicos da Água/metabolismo , Óxido de Zinco/metabolismo , Disponibilidade Biológica , Cádmio/metabolismo , Cobre/metabolismo , Produtos Agrícolas/classificação , Produtos Agrícolas/crescimento & desenvolvimento , Hidroponia , Ferro/metabolismo , Chumbo/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Especificidade da Espécie , Óxido de Zinco/química
16.
J Photochem Photobiol B ; 203: 111748, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31918235

RESUMO

Nanotechnology is an emerged field to develop the plant mediated metal based nanodrugs by green method. In this current study, the zinc oxide metal based nanoparticles were developed using (Clausena lansium (Lour.) Skeels) Peel aqueous extracts and zinc nitrate. The C.L extract zinc nanoparticleswere indicated by the sharp peak seen at 350 nm utilizing the Ultraviolet-Visible spectroscopy (UV-Vis). The high peaks indicate the presence of phytochemicals and its functional groups in ZnONPs were studied by the Fourier Transform Infrared Spectroscopy (FT-IR). The X-Ray Diffraction analysis (XRD) explores the pattern and structure of ZnONPs as spherical and base-centered monoclinic crystalline shapes. The C.L extract with Zn nanoparticles were spherical in nature and the size of the synthesized particles were about 28.42 nm respectively. The autophagy (Beclin-1, LC3-I, LC3-II and ATG4B) and apoptotic (Bax, Bcl-2 and Caspase-3) proteins were regulated by the treatment with ZnONPs in SH-SY5Y neuroblastoma cells. The DNA loss or damage was occurred in the ZnONPs treatment and it was performed using Comet assay. The ZnONPs treatment generates the ROS in the cells and decreased its stability and viability. Addition of NAC prevents ROS in the cultured SH-SY5Y cells and prevents the cells from the apoptosis. We concluded that the ZnONPs potentially kills the neuroblastoma cells by producing the intracellular ROS.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Nanopartículas Metálicas/química , Óxido de Zinco/química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proteína Beclina-1/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Clausena/química , Clausena/metabolismo , Dano ao DNA/efeitos dos fármacos , Química Verde , Humanos , Nanopartículas Metálicas/toxicidade , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Extratos Vegetais/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo
17.
Environ Pollut ; 259: 113867, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31896479

RESUMO

This study aimed to evaluate the impacts of morphological-controlled ZnO nanoarchitectures on aerobic microbial communities during real wastewater treatment in an aerobic-photocatalytic system. Results showed that the antibacterial properties of ZnO nanoarchitectures were significantly more overwhelming than their photocatalytic properties. The inhibition of microbial activities in activated sludge by ZnO nanoarchitectures entailed an adverse effect on wastewater treatment efficiency. Subsequently, the 16S sequencing analysis were conducted to examine the impacts of ZnO nanoarchitectures on aerobic microbial communities, and found the significantly lower microbial diversity and species richness in activated sludge treated with 1D-ZnO nanorods as compared to other ZnO nanoarchitectures. Additionally, 1D-ZnO nanorods reduced the highest proportion of Proteobacteria phylum in activated sludge due to its higher proportion of active polar surfaces that facilitates Zn2+ ions dissolution. Pearson correlation coefficients showed that the experimental data obtained from COD removal efficiency and bacterial log reduction were statistically significant (p-value < 0.05), and presented a positive correlation with the concentration of Zn2+ ions. Finally, a non-parametric analysis of Friedman test and post-hoc analysis confirmed that the concentration of Zn2+ ions being released from ZnO nanoarchitectures is the main contributing factor for both the reduction in COD removal efficiency and bacterial log reduction.


Assuntos
Microbiota , Águas Residuárias , Purificação da Água , Óxido de Zinco , Bactérias/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Esgotos/química , Esgotos/microbiologia , Águas Residuárias/química , Águas Residuárias/microbiologia , Óxido de Zinco/química , Óxido de Zinco/toxicidade
18.
Environ Pollut ; 259: 113902, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31918149

RESUMO

A series of phosphorus containing ZnO (P-ZnO) photocatalysts with various percentages of phosphorus were successfully synthesized using the hydrothermal method. The structural, physical and optical properties of the obtained microparticles were investigated using diverse techniques such as X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, ultraviolet-visible diffusion reflectance spectroscopy (UV-Vis DRS), photoluminescence (PL) spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS) and N2 adsorption-desorption analysis. The photocatalytic activities of the pure and P-ZnO samples were evaluated for the degradation of Rhodamine B (RhB) under visible light irradiation. The parameters such as pH, catalyst dosage, contaminant concentration and effect of persulfate as an oxidant were studied. It was found that the P-ZnO1.8% photocatalyst could destroy 99% of RhB (5 ppm) in 180 min at pH = 7; furthermore, it degraded ∼100% of 5 and 10 ppm of the RhB pollutant in 120 and 180 min, respectively, only by adding 0.01 g of persulfate into the reaction solution. To determine the photocatalytic mechanism, 2-propanol, benzoquinone and EDTA were used and it was indicated that hydroxyl radicals, superoxide ions and holes, all had major roles in the photocatalytic degradation but the hydroxyl radical effect was the most significant. The phenol degradation was also investigated using the P-ZnO1.8% optimum photocatalyst which could destroy 53% of the phenol (5 ppm) in 180 min. According to the reusability test, it was proved that after 5 cycles, the catalyst activity was not highly changed and it was potentially capable of pollutant degradation.


Assuntos
Luz , Fósforo , Purificação da Água/métodos , Óxido de Zinco , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Fósforo/química , Espectroscopia de Infravermelho com Transformada de Fourier , Purificação da Água/instrumentação , Óxido de Zinco/química
19.
Mater Sci Eng C Mater Biol Appl ; 108: 110459, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924031

RESUMO

In this work, a new pH-responsive nanohybrid carrier was prepared with chelating ZnO-dopamine (Zn-d) on the surface of graphene oxide. Doxorubicin (DOX) as a model drug was loaded on the resulted nanohybrid. The characteristics of Zn-d-rGO nanohybrid (NH) determined using Fourier transformed infrared spectroscopy (FT-IR), X-ray Diffraction spectroscopy (XRD), UV-Visible spectroscopy, Scanning Electron Microscope (SEM), EDX and AFM. The BET analysis showed a specific surface area of 37.16 m2/g and the obtained nanohybrid indicated a high loading capacity of DOX up to 99.7%, and the release profile displayed a pH-dependent discharge in the acidic environment for14 days. The cytotoxicity of the prepared nanohybrid was measured against T47D and MCF10A cells and it confirmed that as-prepared nanohybrid has high toxicity against cancer cells and lower effect against human breast cell. Meanwhile, the prepared nanohybrids showed well antimicrobial activity against gram-positive and negative bacteria. The obtained results showed that the prepared nanohybrid (Zn-d-rGO) could potentially be used as a safe carrier for drug delivery systems.


Assuntos
Antibacterianos , Quelantes , Dopamina , Doxorrubicina , Portadores de Fármacos , Grafite , Nanopartículas/química , Óxido de Zinco , Antibacterianos/química , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Linhagem Celular Tumoral , Quelantes/química , Quelantes/farmacocinética , Quelantes/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Dopamina/química , Dopamina/farmacocinética , Dopamina/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Grafite/química , Grafite/farmacocinética , Grafite/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Óxido de Zinco/química , Óxido de Zinco/farmacocinética , Óxido de Zinco/farmacologia
20.
Ecotoxicol Environ Saf ; 191: 110194, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31951903

RESUMO

A novel electrochemical sensor based on zinc oxide/nitrogen doped porous carbons (ZnO/NPC) modified electrode has been constructed for detecting 4-aminophenol (4-AP). The ZnO/NPC material was synthesized by one-step carbonization of MOF-5-NH2. The modified glassy carbon electrode (ZnO/NPC/GCE) holds excellent electrocatalytic activity toward 4-AP, with a sensitivity of about 31.02 µA/µM/cm2. Under optimal conditions, its oxidation peak current increases linearly with the increasing concentration of 4-AP (from 5 to 120 µmol/L), and the detection limits is 0.014 µmol/L (S/N = 3). Furthermore, favorable selectivity, superior reproducibility and outstanding stability have been achieved. The ZnO/NPC/GCE has been applied in detecting 4-AP in industrial waste water and achieved positive results with the recovery of 4-AP ranging from 94.02% to 107.7%, which confirms that this sensor is a reliable platform for the detection of 4-AP in waste water.


Assuntos
Aminofenóis/análise , Técnicas Eletroquímicas/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Carbono/química , Eletrodos , Limite de Detecção , Nanoporos , Reprodutibilidade dos Testes , Óxido de Zinco/química
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