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1.
Environ Sci Pollut Res Int ; 30(18): 53817-53832, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36864335

RESUMO

The growing concern about the environmental consequences of anthropogenic CO2 emissions significantly stimulated the research of low-cost, efficient, and recyclable solid adsorbents for CO2 capture. In this work, a series of MgO-supported mesoporous carbon nitride adsorbents with different MgO contents (xMgO/MCN) was prepared using a facile process. The obtained materials were tested for CO2 capture from 10 vol% CO2 mixture gas with N2 using a fixed bed adsorber at atmospheric pressure. At 25 ºC, the bare MCN support and unsupported MgO samples demonstrated CO2 capture capacities of 0.99, and 0.74 mmol g-1, respectively, which were lower than those of the xMgO/MCN composites.The incorporation of MgO into the MCN improved the CO2 uptake, and the 20MgO/MCN exhibited the highest CO2 capture capacity of 1.15 mmol g-1 at 25 °C. The improved performance of the 20MgO/MCN nanohybrid can be possibly assigned to the presence of high content of highly dispersed MgO NPs along with its improved textural properties in terms of high specific surface area (215 m2g-1), large pore volume (0.22 cm3g-1), and abundant mesoporous structure. The efffects of temperature and CO2 flow rate were also investigated on the CO2 capture performance of 20MgO/MCN. Temperature was found to have a negative influence on the CO2 capture capacity of the 20MgO/MCN, which decreased from 1.15 to 0.65 mmol g-1with temperature rise from 25 C to 150º C, due to the endothermicity of the process. Similarly, the capture capacity decreased from 1.15 to 0.54 mmol g-1 with the increase of the flow rate from 50 to 200 ml minute-1 respectively. Importantly, 20MgO/MCN showed excellent reusability with consistent CO2 capture capacity over five sequential sorption-desorption cycles, suggesting its suitability for the practical capture of CO2.


Assuntos
Dióxido de Carbono , Óxido de Magnésio , Dióxido de Carbono/química , Óxido de Magnésio/química , Adsorção , Nitrilas
2.
Mini Rev Med Chem ; 23(9): 1058-1069, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36515021

RESUMO

In the current epoch, noble metals/metal oxides with precise structures are needed to develop sustainable products to improve the welfare of human beings and the environment. Nanomaterials in the regime 1 -100 nm scale are a promising material for the research fraternities owing to their stupendous properties. The metallic/metal oxide nanoparticles (silver, gold, copper oxide, iron oxide, magnesium oxide) are gaining significant momentum and need to be extensively studied. Magnesium oxide nanoparticles (MgONPs) are a periclase, white hygroscopic material consisting of Mg2+ ions and O-2 ions in lattice arranged. These nanoparticles can be fabricated through physical, chemical and biological methods. The development of green synthesized MgONPs needs to be ascertained and explored its ultimate in medicine, health, cosmetics, environmental protection, chemical industries, and energy. Therefore, the present review manifests the green synthetic approaches of MgONPs and their impact on crystalline structure and shape. Further, we have provided the antibacterial and anticancer activities of MgONPs thoroughly reported in various kinds of literature. Overall, the unique MgONPs can be plausibly used as safe biomaterials in biomedical applications.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Humanos , Óxido de Magnésio/farmacologia , Óxido de Magnésio/química , Nanopartículas Metálicas/química , Óxidos/química , Antibacterianos/farmacologia , Antibacterianos/química
3.
Molecules ; 27(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36014400

RESUMO

The present study describes the green biofunctional synthesis of magnesium oxide (MgO) nanoparticles using the aqueous Tarenna asiatica fruit extract. The characterization of Tarenna asiatica fruit extract MgO nanoparticles (TAFEMgO NPs) was achieved by X-ray powder diffraction, UV-Vis spectroscopy, FTIR, TEM, SEM, and energy-dispersive X-ray diffraction. TAFEMgO NPs scavenged the DPPH free radicals with an IC50 value of 55.95 µg/µL, and it was highly significant compared to the standard. To authenticate the observed antioxidant potential of TAFEMgO NPs, oxidative stress was induced in red blood cells (RBC) using sodium nitrite (NaNO2). Interestingly, TAFEMgO NPs ameliorated the RBC damage from oxidative stress by significantly restoring the stress parameters, such as the protein carbonyl content (PCC), lipid peroxidation (LPO), total thiol (TT), super-oxide dismutase (SOD), and catalase (CAT). Furthermore, oxidative stress was induced in-vivo in Sprague Dawley female rats using diclofenac (DFC). TAFEMgO NPs normalized the stress parameters in-vivo and minimized the oxidative damage in tissues. Most importantly, TAFEMgO NPs restored the function and architecture of the damaged livers, kidneys, and small intestines by regulating biochemical parameters. TAFEMgO NPs exhibited an anticoagulant effect by increasing the clotting time from 193 s in the control to 885 s in the platelet rich plasma. TAFEMgO NPs prolonged the formation of the clot process in the activated partial thromboplastin time and the prothrombin time, suggest the effective involvement in both intrinsic and extrinsic clotting pathways of the blood coagulation cascade. TAFEMgO NPs inhibited adenosine di-phosphate (ADP)-induced platelet aggregation. TAFEMgO NPs did not show hemolytic, hemorrhagic, and edema-inducing properties at the tested concentration of 100 mg/kgbody weight, suggesting its non-toxic property. In conclusion, TAFEMgO NPs mitigates the sodium nitrite (NaNO2)- and diclofenac (DFC)-induced stress due to oxidative damage in both in vitro and in vivo experimental models.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Trombose , Animais , Diclofenaco/farmacologia , Feminino , Óxido de Magnésio/química , Óxido de Magnésio/farmacologia , Nanopartículas Metálicas/química , Nanopartículas/química , Estresse Oxidativo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Carbonilação Proteica , Ratos , Ratos Sprague-Dawley , Nitrito de Sódio/farmacologia
4.
Biomater Adv ; 138: 212855, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35913247

RESUMO

The use of chemically synthesized nanoparticles and crude plant extracts as antimicrobial -anticancer agents have many limitations. In this study, we have used Centella asiatica extract (CaE) having relatively less explored but tremendous medicinal properties, as reducing and stabilizing agents to green synthesize magnesium oxide nanoparticles (MgONPs) using magnesium nitrate. In comparison to the bulk material, capabilities of Ca-MgONPs as an improved antibacterial, antifungal, and anticancer agent in human prostatic carcinoma cells (PC3), as well as membranolytic capability in model cell membrane, were studied. The phyto-functionalized Ca-MgONPs were characterized using UV-Visible spectroscopy (UV-Vis), Transmission Electron Microscopy (TEM), Energy Dispersive X-Ray Spectroscopy (EDX), X-ray Diffraction (XRD), Fourier Transform Infra-Red Spectroscopy (FT-IR) and Atomic Force Microscopy (AFM). Observation of characteristic peaks by spectroscopic and microscopic analysis confirmed the synthesis of Ca-MgONPs. The Ca-MgONPs showed broad spectrum of bactericidal activity against both gram-positive and gram-negative bacteria and fungicidal activity against two species of the Candida fungus. The Ca-MgONPs also exhibited dose-dependent and selective inhibition of proliferating PC3 cells with IC50 of 123.65 ± 4.82 µg/mL at 24 h, however, without having any cytotoxicity toward non-cancerous HEK293 cells. Further studies aimed at understanding the probable mechanism of toxicity of Ca-MgONPs in PC3 cells, the results indicated a significant reduction in cell migration capacities, increment in cytosolic ROS, loss of mitochondrial transmembrane potential, DNA damage and S-phase cell cycle arrest. Ca-MgONPs also induced pore formation in a synthetic large unilamellar vesicle. Thus, Ca-MgONPs might be useful in the effective management of several human pathogens of concern and some more cancer types.


Assuntos
Anti-Infecciosos , Centella , Nanopartículas Metálicas , Antibacterianos/farmacologia , Anti-Infecciosos/química , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Química Verde , Células HEK293 , Humanos , Óxido de Magnésio/química , Nanopartículas Metálicas/uso terapêutico , Extratos Vegetais , Espectroscopia de Infravermelho com Transformada de Fourier , Triterpenos
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 278: 121372, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-35588606

RESUMO

In this study, the acceleratory effect of magnesium oxide nanoparticles (MgO NPs) on the amyloid fibrillization of human tau protein, a major protein involved in the onset of Alzheimer's disease (AD) was investigated. The MgO NPs were fabricated through laser ablation synthesis in solution (LASiS), well-characterized, and explored further for tau aggregation and relevant neurotoxicity by different assays. The results showed that the MgO NPs have a size of around 30 nm, a hydrodynamic radius of 57.09 nm, and a zeta potential of -18.06 mV. The data from ThT and ANS fluorescence-based assays along with circular dichroism (CD) spectroscopy clearly indicated that MgO NPs could significantly promote tau fibrillization, concentration-dependently. Considering the acceleratory effect of MgO NPs against tau fibrillization, cellular assays including cell viability, reactive oxygen species (ROS), and caspase-3 assays indicated that the neurotoxicity of tau amyloid fibrils formed with MgO NPs was higher than that of tau samples aged alone against N2a neuron-like cells. Therefore, it was concluded that the interaction of MgO NPs with tau can lead to acceleration of tau aggregation and underlying neurotoxicity. This study, then can provide useful information about the direct effect of MgO NPs against memory proteins and subsequent adverse effects.


Assuntos
Terapia a Laser , Nanopartículas , Idoso , Amiloide , Humanos , Óxido de Magnésio/química , Nanopartículas/química , Nanopartículas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Proteínas tau
6.
Sci Total Environ ; 831: 154751, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35341874

RESUMO

The metal catalysts X-Mo@MgO (X = Ni, Fe, Co) was studied as excellent catalyst for catalytic pyrolysis conversion of biomass and plastics into functional carbon nanocomposite. The proper reaction mechanism of the process was explored through the gas composition, and explored the bactericidal performance of functional carbon nanocomposite. The results showed that the Ni, Fe and Co-based catalysts elevated H2 gas yield reached to 57%, 34% and 44% as the addition of Mo, due to Mo or its oxide species for scission of small molecule compound. The introduction of NiMo@MgO catalyst produced lower CH4, and higher H2 and MWCNTs, which indicated that the formation of MWCNTs is mainly attributed to CH4 dehydrogenation. As a comparison, FeMo@MgO catalyst for CO disproportionation reaction could generate more MWCNTs and lower H2. The functional carbon nanocomposite from FeMo@MgO catalyst were comprehensively evaluated by multiple characterizations. TPO and Raman results confirmed that FeMo@MgO catalyst can provide an excellent carrier to generate MWCNTs with few defects and high graphitization. The functional carbon nanocomposite were initially applied to E.coli extinguishing. The core-shell structure catalyst not only has excellent bactericidal performance, but also has strong resistance to metal leaching.


Assuntos
Nanocompostos , Pirólise , Biomassa , Carbono , Catálise , Óxido de Magnésio/química , Metais , Plásticos
7.
Food Chem Toxicol ; 159: 112725, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34856315

RESUMO

Synthetic food colorants are extensively used across the globe regardless of the fact that they induce deleterious side effects when used in higher amounts. In this work, a novel electrochemical sensor based on nickel nanoparticles doped lettuce-like Co3O4 anchored graphene oxide (GO) nanosheets was developed for effective detection of sulfonated azo dye sunset yellow widely used as a food colorant. Hydrothermal synthesis was adopted for the preparation of lettuce-like spinel Co3O4 nanoparticles and Ni-Co3O4 NPs/GO nanocomposite was prepared using ecofriendly and economical sonochemical method. The prepared ternary nanocomposite meticulously fabricated on a screen-printed carbon electrode exhibited remarkable electrocatalytic activity towards sunset yellow determination. This is apparent from the resultant well-defined and intense redox peak currents of Ni-Co3O4 NPs/GO nanocomposite modified electrode at very low potentials. The developed sunset yellow sensor exhibited a high sensitivity of 4.16 µA µM-1 cm-2 and a nanomolar detection limit of 0.9 nM in the linear range 0.125-108.5 µM. Furthermore, experiments were conducted to affirm excellent stability, reproducibility, repeatability, and selectivity of proposed sensor. The practicality of sunset yellow determination using the developed sensor was analyzed in different varieties of food samples including jelly, soft drink, ice cream, and candy resulting in recovery in the range of 96.16%-102.56%.


Assuntos
Compostos Azo/análise , Técnicas Eletroquímicas/métodos , Corantes de Alimentos/análise , Nanopartículas Metálicas/química , Nanocompostos/química , Óxido de Alumínio/química , Cobalto/química , Grafite , Limite de Detecção , Modelos Lineares , Óxido de Magnésio/química , Níquel/química , Óxidos/química , Reprodutibilidade dos Testes
8.
J Mater Chem B ; 9(4): 1107-1122, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33427267

RESUMO

Bone repair and regeneration processes are markedly impaired in diabetes mellitus (DM). Intervening approaches similar to those developed for normal healing conditions have been adopted to combat DM-associated bone regeneration. However, limited outcomes were achieved for these approaches. Hence, together with osteoconductive hydroxyapatite (HA) nanocrystals, osteoinductive magnesium oxide (MgO) nanocrystals were uniformly mounted into the network matrix of an organic hydrogel composed of cysteine-modified γ-polyglutamic acid (PGA-Cys) to construct a hybrid and rough hydrogel scaffold. It was hypothesized that the HA/MgO nanocrystal hybrid hydrogel (HA/MgO-H) scaffold can significantly promote bone repair in DM rats via the controlled release of Mg2+. The HA/MgO-H scaffold exhibited a sponge-like morphology with porous 3D networks inside it and displayed higher mechanical strength than a PGA-Cys scaffold. Meanwhile, the HA/MgO-H scaffold gradually formed a tough hydrogel with G' of more than 1000 Pa after hydration, and its high hydration swelling ratio was still retained. Moreover, after the chemical degradation of the dispersed MgO nanocrystals, slow release of Mg2+ from the hydrogel matrix was achieved for up to 8 weeks because of the chelation between Mg2+ and the carboxyl groups of PGA-Cys. In vitro cell studies showed that the HA/MgO-H scaffold could not only effectively promote the migration and proliferation of BMSCs but could also induce osteogenic differentiation. Moreover, in the 8th week after implanting the HA/MgO-H scaffold into femur bone defect zones of DM rats, more effective bone repair was presented by micro-CT imaging. The bone mineral density (397.22 ± 16.36 mg cm-3), trabecular thickness (0.48 ± 0.07 mm), and bone tissue volume/total tissue volume (79.37 ± 7.96%) in the HA/MgO-H group were significantly higher than those in the other groups. Moreover, higher expression of COL-I and OCN after treatment with HA/MgO-H was also displayed. The bone repair mechanism of the HA/MgO-H scaffold was highly associated with reduced infiltration of pro-inflammatory macrophages (CD80+) and higher angiogenesis (CD31+). Collectively, the HA/MgO-H scaffold without the usage of bioactive factors may be a promising biomaterial to accelerate bone defect healing under diabetes mellitus.


Assuntos
Materiais Biocompatíveis/farmacologia , Regeneração Óssea/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Hidrogéis/farmacologia , Hipoglicemiantes/farmacologia , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/patologia , Modelos Animais de Doenças , Durapatita/química , Durapatita/farmacologia , Hidrogéis/síntese química , Hidrogéis/química , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , Óxido de Magnésio/química , Óxido de Magnésio/farmacologia , Masculino , Camundongos , Nanopartículas/química , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Estreptozocina/administração & dosagem , Estresse Mecânico , Propriedades de Superfície
9.
PLoS One ; 15(8): e0237567, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797097

RESUMO

Distinct morphological MgO nanoparticles (MgONPs) were synthesized using biomasses of Saussurea costus roots. The biomass of two varieties of Saussurea costus (Qustal hindi and Qustal bahri) were used in the green synthesis of MgONPs. The physical and chemical features of nanoparticles were confirmed by spectroscopic and microscopic techniques. The surface morphology of the obtained nanoparticles was detected at different magnifications by SEM and TEM microscopy and the size of nanoparticles were found to be 30 and 34 nm for Qustal hindi and Qustal bahri, respectively. The antimicrobial activity of the prepared MgONPs was screened against six pathogenic strains. The synthesized nanoparticles by Qustal bahri biomass exerted significant inhibition zones 15, 16, 18, 17, 14, and 10 mm against E. coli, P. aeruginosa, C. tropicalis and C. glabrata, S. aureus and B. subtilis as compared to those from Qustal hindi 12, 8 and 17 mm against B. subtilis, E. coli and C. tropicalis, respectively. MgONPs showed a potential cytotoxicity effect against MCF-7 breast cancer cell lines. Cellular investigations of MgONPs revealed that the prepared nanoparticles by Qustal bahri exhibited high cytotoxicity against MCF-7 cancer cell lines. IC50 values in MCF-7 cells were found to be 67.3% and 52.1% for MgONPs of Saussurea costus biomasses, respectively. Also, the photocatalytic activity of MgONPs of each Saussurea costus variety was comparatively studied. They exhibited an enhanced photocatalytic degradation of methylene blue after UV irradiation for 1 h as 92% and 59% for those prepared by Qustal bahri and Qustal hindi, respectively. Outcome of results revealed that the biosynthesized MgONPs showed promising biomedical potentials.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Óxido de Magnésio/farmacologia , Azul de Metileno/química , Saussurea/química , Anti-Infecciosos/química , Antineoplásicos/química , Bactérias/efeitos dos fármacos , Biomassa , Catálise , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Fungos/efeitos dos fármacos , Química Verde , Humanos , Células MCF-7 , Óxido de Magnésio/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Processos Fotoquímicos , Extratos Vegetais/química , Raízes de Plantas/química
10.
J Biomed Mater Res B Appl Biomater ; 108(7): 2961-2970, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32386283

RESUMO

In the current study, electrospun poly(ε-caprolactone)-gelatin (PCL-Gel) fibrous scaffolds containing magnesium oxide (MgO) particles and preseeded with human endometrial stem cells (hEnSCs) were developed to use as wound care material in skin tissue engineering applications. Electrospun fibers were fabricated using PCL-Gel (1:1 [wt/wt]) with different concentrations of MgO particles (1, 2, and 4 wt%). The fibrous scaffolds were evaluated regarding their microstructure, mechanical properties, surface wettability, and in vitro and in vivo performances. The full-thickness excisional wound model was used to evaluate the in vivo wound healing ability of the fabricated scaffolds. Our findings confirmed that the wounds covered with PCL-Gel fibrous scaffolds containing 2 wt% MgO and preseeded with hEnSCs have nearly 79% wound closure ability while sterile gauze showed 11% of wound size reduction. Our results can be employed for biomaterials aimed at the healing of full-thickness skin wounds.


Assuntos
Endométrio/metabolismo , Gelatina/química , Óxido de Magnésio/química , Poliésteres/química , Pele/metabolismo , Células-Tronco/metabolismo , Alicerces Teciduais/química , Cicatrização , Ferimentos e Lesões , Animais , Feminino , Xenoenxertos , Humanos , Masculino , Porosidade , Ratos , Ratos Wistar , Transplante de Células-Tronco , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/terapia
11.
Clin Transl Oncol ; 22(10): 1875-1884, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32170638

RESUMO

PURPOSE: The limitation of surgery, radiotherapy and chemotherapy in the treatment of cancer and the rise of the application of nanomaterials in the field of biomedicine have promoted the application of various nanomaterials in the combination of radiotherapy and chemotherapy in the treatment of cancer. To improve the efficiency of cancer treatment, the multifunctional nanocomposites MGO/FU-MI (MGO/FU-MI NCs) were used for combination chemotherapy and radiotherapy to verify its effectiveness in treating tumors. METHODS: The proliferation activity of MGO/FU-MI NCs on MC-38 and B16 cells was detected by CCK-8, and the level of apoptosis and reactive oxygen species were detected by flow cytometry. To verify its efficacy in the combination of chemoradiotherapy, different treatment regimens were developed for several groups of tumor-bearing mice. RESULTS: The MGO/FU-MI NCs can induce apoptosis, stimulate ROS production, and inhibit cell proliferation. In vivo experiments, when MGO/FU-MI NCs are used alone for chemotherapy, have a certain therapeutic effect on mouse tumors. When MGO/FU-MI NCs are combined with radiation, the tumor volume can be significantly reduced and the survival time of mice is significantly prolonged. CONCLUSION: The MGO/FU-MI NCs are very effective in the treatment of tumors when combined with radiotherapy and chemotherapy, and have the potential to be a combination of radiotherapy and chemotherapy.


Assuntos
Quimiorradioterapia , Fluoruracila/administração & dosagem , Óxido de Magnésio/administração & dosagem , Metronidazol/administração & dosagem , Nanocompostos/administração & dosagem , Neoplasias/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fluoruracila/química , Fluoruracila/farmacologia , Humanos , Óxido de Magnésio/química , Óxido de Magnésio/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Nanocompostos/química , Neoplasias/metabolismo , Neoplasias/patologia , Tolerância a Radiação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
12.
Molecules ; 25(4)2020 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-32079079

RESUMO

Inorganic-organic hybrids are a group of materials that have recently become the subject of intense scientific research. They exhibit some of the specific properties of both highly durable inorganic materials (e.g., titanium dioxide, zinc) and organic products with divergent physicochemical traits (e.g., lignin, chitin). This combination results in improved physicochemical, thermal or mechanical properties. Hybrids with defined characteristics can be used as fillers for polymer composites. In this study, three types of filler with different MgO/lignin ratio were used as fillers for polypropylene (PP). The effectiveness of MgO-lignin binding was confirmed using Fourier transform infrared spectroscopy. The fillers were also tested in terms of thermal stability, dispersive-morphological properties as well as porous structure. Polymer composites containing 3 wt.% of each filler were subjected to wide angle X-ray diffraction tests, differential scanning calorimetry and microscopic studies to define their structure, morphology and thermal properties. Additionally, tensile tests of the composites were performed. It was established that the composition of the filler has a significant influence on the crystallization of polypropylene-either spherulites or transcrystalline layers were formed. The value of Young's modulus and tensile strength remained unaffected by filler type. However, composites with hybrid fillers exhibited lower elongation at break than unfilled polypropylene.


Assuntos
Lignina/química , Óxido de Magnésio/química , Manufaturas/análise , Polipropilenos/química , Cristalização , Módulo de Elasticidade , Humanos , Teste de Materiais , Porosidade , Estresse Mecânico , Resistência à Tração
13.
Sci Rep ; 10(1): 1890, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024952

RESUMO

Asian citrus psyllid (Diaphorina citri) vectors the bacterium Candidatus Liberibacter asiaticus, the causal pathogen of citrus greening disease that is devastating citrus industries worldwide. Suppressing psyllid populations is crucial to prevent disease spread. An attract-and-kill trap based on psyllid behavior would fill a niche for monitoring and control. To optimize visual attraction of psyllids, the ultraviolet (UV) reflective properties of magnesium oxide (MgO) and/or barium sulfate (BaSO4) were assessed for potential application to a trap surface. Under low UV, high UV and natural sunlight conditions, the reflectance, attraction, and probing behaviors of psyllids were evaluated on surfaces containing magnesium oxide or barium sulfate. Magnesium oxide added to yellow sticky traps enhanced visual response of D. citri. Probing assays demonstrated that magnesium oxide alone or as a mixture with a phagostimulant blend, increased the UV reflectance of substrates, as well as, attraction and probing by psyllids. Results demonstrated that psyllids respond to both short (UV) and long (yellow) wavelengths during orientation, and that these inert compounds can increase UV reflectance and improve attractiveness of an attract-and-kill device.


Assuntos
Citrus/microbiologia , Hemípteros/fisiologia , Controle de Insetos/métodos , Insetos Vetores/microbiologia , Doenças das Plantas/prevenção & controle , Animais , Comportamento Animal/fisiologia , Bioensaio , Proteção de Cultivos/métodos , Sinais (Psicologia) , Hemípteros/microbiologia , Óxido de Magnésio/química , Óxido de Magnésio/efeitos da radiação , Doenças das Plantas/microbiologia , Rhizobiaceae/patogenicidade , Raios Ultravioleta , Visão Ocular/fisiologia
14.
Chem Biodivers ; 17(3): e1900608, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32017363

RESUMO

This research investigates an efficient dual valorization of olive mill wastewater in the biosynthesis of magnesium oxide nanoparticles and in the depollution of the effluent by Yarrowia lipolytica growth evaluation. After removal of polyphenols, the recovered biophenols were reacted with the magnesium precursor to provide magnesium oxide nanoparticles. In order to confirm the biosynthesized magnesium oxide nanoparticles, several analyses were undertaken. The Fourier transform infrared spectrum gives a broad absorption at 658 cm-1 confirming the presence of the magnesium oxide nanoparticles, while the UV/VIS absorption spectroscopy reveals an intense transition with a maximum absorption at 300 nm. The X-ray diffraction and transmission electron microscopy analyses show that nanoparticles are in pure cubic crystalline with spherical and hexagonal shapes (average size is 19.4 nm). The zeta potential analysis illustrates a negative potential proving a good stability of the biosynthesized nanoparticles. Nanoparticles were assigned for their in vitro antibacterial activity against Escherichia coli, Enterobacter aerogenes, Salmonella typhimurium, Staphylococcus cohnii, and Bacillus niacini. The evaluation of the growth of Yarrowia lipolytica on the recovered olive mill wastewater after removal of polyphenols yielded 3.2 g/L of the Yarrowia biomass in 72 h without nutriment additions, providing an important decrease of chemical oxygen demand (73 %).


Assuntos
Antibacterianos/farmacologia , Óxido de Magnésio/farmacologia , Olea/química , Águas Residuárias/química , Yarrowia/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Bacillus/efeitos dos fármacos , Biomassa , Enterobacter aerogenes/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Óxido de Magnésio/química , Óxido de Magnésio/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Nanopartículas/química , Tamanho da Partícula , Salmonella typhimurium/efeitos dos fármacos , Staphylococcus/efeitos dos fármacos , Propriedades de Superfície , Yarrowia/crescimento & desenvolvimento
15.
Mater Sci Eng C Mater Biol Appl ; 108: 110486, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924055

RESUMO

The poor interfacial bonding and resultant agglomeration of nanoparticles in polymer-based composite severely deteriorated their reinforcement effect. In this work, MgO nanoparticles (MgO-NPs) were surface modified with Poly (L-lactic acid-co-malic acid) (PLMA) to improve the interfacial compatibility in Poly-l-lactic acid (PLLA) scaffold manufactured by selective laser sintering. PLMA possess a hydrophilic end with carboxyl group (comes from the malic acid) and an l-lactic acid chain. On one hand, the carboxyl group was able to form hydrogen bonding with the hydroxyl groups of MgO-NPs. On the other hand, the l-lactic acid chain containing the hydroxyl groups could react with the carboxyl group of PLLA. Results revealed that the scaffold exhibited significantly enhanced compressive strength and modulus by 47.1% and 237.7%, respectively, which could be ascribed to the enhanced interfacial bonding between PLLA and MgO-NPs, as well as the rigid particle reinforcement. In addition, the scaffold was favorable for cell adhesion, proliferation and differentiation, owing to the improved hydrophilic and suitable pH environment. It was suggested the scaffold was a promising material for bone repair application.


Assuntos
Materiais Biocompatíveis/química , Osso e Ossos/química , Óxido de Magnésio/química , Poliésteres/química , Propriedades de Superfície , Alicerces Teciduais/química , Osso e Ossos/fisiologia , Adesão Celular , Linhagem Celular Tumoral , Força Compressiva , Humanos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Lasers , Microscopia Eletrônica de Transmissão , Porosidade , Pós , Estresse Mecânico , Engenharia Tecidual/métodos
16.
Int J Biol Macromol ; 142: 254-264, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31593725

RESUMO

Nanocomposite hydrogels composed of magnesium oxide (MgO) and natural polymer-based copolymer of Xanthan gum (Xan) and acrylic acid (AAc) were prepared using radiation-induced copolymerization and crosslinking technique to be used as a drug delivery system. MgO nanoparticles were synthesized using sol- gel method. FTIR, XRD, UV-vis and TEM analysis revealed the successful preparation of MgO nanoparticles. The size of MgO nanoparticles was found to be 6.6 nm. FTIR data confirmed the incorporation of MgO within the (Xan-AAc) copolymer hydrogel. The presence of MgO nanoparticles slightly decreases the gelation degree and on contrary the swelling degree and network porosity was enhanced. (Xan-AAc)/MgO nanocomposites show typical pH-dependent swelling behavior Moreover, the swelling kinetics showed that all the samples under investigation possess Fickian at pH1 and non-Fickian at pH7. Methotrexate (MTX) as model for anticancer drugs was used to evaluate the potential efficiency of the obtained (Xan-AAc)/MgO nanocomposites as drug carrier. Incorporation of MgO into (Xan-AAc) hydrogel improves the drug loading efficiency and enhances the (MTX) release to reach maximum in the simulated intestine medium (pH7). The drug release profile came in a good agreement with swelling results which recommend the (Xan-AAc)/MgO nanocomposite hydrogels as potential targeted drug delivery system.


Assuntos
Acrilatos/química , Portadores de Fármacos , Hidrogéis/química , Óxido de Magnésio/química , Metotrexato/administração & dosagem , Nanocompostos/química , Polissacarídeos Bacterianos/química , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Técnicas de Química Sintética , Sistemas de Liberação de Medicamentos , Raios gama , Humanos , Concentração de Íons de Hidrogênio , Nanocompostos/ultraestrutura , Análise Espectral
17.
Adv Mater ; 32(4): e1904011, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31793717

RESUMO

Biodegradable nanoprodrugs, inheriting the antitumor effects of chemotherapy drugs and overcoming the inevitable drawback of side effects on normal tissues, hold promise as next-generation cancer therapy candidates. Biodegradable nanoprodrugs of transferrin-modified MgO2 nanosheets are developed to selectively deliver reactive oxygen species to cancer cells for molecular dynamic therapy strategy. The nanosheets favor the acidic and low catalase activity tumor microenvironment to react with proton and release nontoxic Mg2+ . This reaction simultaneously produces abundant H2 O2 to induce cell death and damage the structure of transferrin to release Fe3+ , which will react with H2 O2 to produce highly toxic ·OH to kill tumor cells.


Assuntos
Nanopartículas/química , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/uso terapêutico , Peróxido de Hidrogênio/toxicidade , Óxido de Magnésio/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Pró-Fármacos/metabolismo , Pró-Fármacos/uso terapêutico , Pró-Fármacos/toxicidade , Espécies Reativas de Oxigênio/uso terapêutico , Espécies Reativas de Oxigênio/toxicidade , Transferrinas/química
18.
Angew Chem Int Ed Engl ; 59(4): 1682-1688, 2020 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-31710768

RESUMO

Sonodynamic therapy (SDT) has the advantages of high penetration, non-invasiveness, and controllability, and it is suitable for deep-seated tumors. However, there is still a lack of effective sonosensitizers with high sensitivity, safety, and penetration. Now, ultrasound (US) and glutathione (GSH) dual responsive vesicles of Janus Au-MnO nanoparticles (JNPs) were coated with PEG and a ROS-sensitive polymer. Upon US irradiation, the vesicles were disassembled into small Janus Au-MnO nanoparticles (NPs) with promoted penetration ability. Subsequently, GSH-triggered MnO degradation simultaneously released smaller Au NPs as numerous cavitation nucleation sites and Mn2+ for chemodynamic therapy (CDT), resulting in enhanced reactive oxygen species (ROS) generation. This also allowed dual-modality photoacoustic imaging in the second near-infrared (NIR) window and T1 -MR imaging due to the released Mn2+ , and inhibited orthotopic liver tumor growth via synergistic SDT/CDT.


Assuntos
Ouro/química , Neoplasias Hepáticas/genética , Óxido de Magnésio/química , Ultrassonografia/métodos , Carcinógenos , Humanos , Nanopartículas
19.
J Hazard Mater ; 385: 121559, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-31732344

RESUMO

Adsorption is a widely used process for removal of heavy metals, but the management of spent adsorbent containing concentrated amounts of heavy metals is a problem due to potential risk of groundwater contamination from leaching of heavy metals. Generally, cementitious binder and additives are used for stabilization and solidification treatment, however heavy metals tend to leach from such matrices. Therefore, this research investigated the effectiveness of chemically modified phosphate biochar (CMPB) composite for the simultaneous solidification and stabilization of arsenic (As) and iron (Fe) contaminated canola meal biochar. Results showed that the performance of spent biochar added CMPB composites was significantly better than the pure composites (without biochar) due to filling of inter-aggregate pores using biochar and availability of sufficient amount of MgKPO4 for binding of biochar particles. Moreover, leaching test and risk assessment studies indicated that there is no potential adverse effect as the concentrations of As and Fe in TCLP leachate were well below the Universal Treatment Standard (UTS) in optimized CMPB composites. In conclusion, chemically modified phosphate binders were found effective in stabilization and solidification of As and Fe contaminated biochar into thermodynamically stable material with high immobilization capacity and low leachability.


Assuntos
Arsênio/química , Carvão Vegetal/química , Ferro/química , Fosfatos/química , Poluentes Químicos da Água/química , Adsorção , Arsênio/análise , Brassica napus/química , Compostos de Cálcio/química , Ferro/análise , Óxido de Magnésio/química , Óxidos/química , Medição de Risco , Poluentes Químicos da Água/análise
20.
Mater Sci Eng C Mater Biol Appl ; 107: 110314, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761184

RESUMO

This review focuses on the biomedical applications and toxicity of spinel ferrite nanoparticles (SFNPs) with more emphasis on the recently published work. A critical review is provided on recent advances of SFNPs applications in biomedical areas. The novelty of SFNPs in addressing the bottleneck problems encountered in the areas of health; in particular, for diagnosis and treatment of tumour cells are well reviewed. Furthermore, research gaps, toxicity of SFNPs and areas which still need more attention are highlighted. Based on the result of this review, the SFNPs have unlimited capacity in cancer treatment, disease diagnosis, magnetic resonance imaging, drug delivery and release. Overall, stepping out of the conventional way of treatment is difficult but also essential in bringing long lasting solution for cancer and other diseases treatment. In fact, the toxicity study and commercialisation of the SFNPs based cancer treatment options are the main challenges and need further study, in order to reduce unforeseen consequences.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Hipertermia Induzida/métodos , Nanocompostos/química , Nanocompostos/uso terapêutico , Nanopartículas/química , Nanopartículas/uso terapêutico , Óxido de Alumínio/química , Animais , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Compostos Férricos/química , Humanos , Óxido de Magnésio/química , Nanocompostos/toxicidade , Nanopartículas/toxicidade , Neoplasias/diagnóstico
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