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[PMID]:29200844
[Au] Autor:Al-Hada NM; Mohamed Kamari H; Abdullah CAC; Saion E; Shaari AH; Talib ZA; Matori KA
[Ad] Endereço:Department of Physics, Faculty of Science.
[Ti] Título:Down-top nanofabrication of binary (CdO) (ZnO) nanoparticles and their antibacterial activity.
[So] Source:Int J Nanomedicine;12:8309-8323, 2017.
[Is] ISSN:1178-2013
[Cp] País de publicação:New Zealand
[La] Idioma:eng
[Ab] Resumo:In the present study, binary oxide (cadmium oxide [CdO]) (zinc oxide [ZnO]) nanoparticles (NPs) at different concentrations of precursor in calcination temperature were prepared using thermal treatment technique. Cadmium and zinc nitrates (source of cadmium and zinc) with polyvinylpyrrolidone (capping agent) have been used to prepare (CdO) (ZnO) NPs samples. The sample was characterized by X-ray diffraction (XRD), scanning electron microscopy, energy-dispersive X-ray (EDX), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy. XRD patterns analysis revealed that NPs were formed after calcination, which showed a cubic and hexagonal crystalline structure of (CdO) (ZnO) NPs. The phase analysis using EDX spectroscopy and FTIR spectroscopy confirmed the presence of Cd and Zn as the original compounds of prepared (CdO) (ZnO) NP samples. The average particle size of the samples increased from 14 to 33 nm as the concentration of precursor increased from x=0.20 to x=0.80, as observed by TEM results. The surface composition and valance state of the prepared product NPs were determined by X-ray photoelectron spectroscopy (XPS) analyses. Diffuse UV-visible reflectance spectra were used to determine the optical band gap through the Kubelka-Munk equation; the energy band gap was found to decrease for CdO from 2.92 to 2.82 eV and for ZnO from 3.22 to 3.11 eV with increasing x value. Additionally, photoluminescence (PL) spectra revealed that the intensity in PL increased with an increase in particle size. In addition, the antibacterial activity of binary oxide NP was carried out in vitro against ATCC 25922 Gram (-ve), ATCC 10708, and UPMC 1175 Gram (+ve). This study indicated that the zone of inhibition of 21 mm has good antibacterial activity toward the Gram-positive UPMC 1175.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Compostos de Cádmio/química
Nanopartículas/química
Óxidos/química
Óxido de Zinco/química
[Mh] Termos MeSH secundário: Antibacterianos/química
Bacillus subtilis/efeitos dos fármacos
Compostos de Cádmio/farmacologia
Avaliação Pré-Clínica de Medicamentos/métodos
Escherichia coli/efeitos dos fármacos
Testes de Sensibilidade Microbiana
Microscopia Eletrônica de Varredura
Microscopia Eletrônica de Transmissão
Óxidos/farmacologia
Tamanho da Partícula
Espectroscopia Fotoeletrônica
Salmonella/efeitos dos fármacos
Espectroscopia de Infravermelho com Transformada de Fourier
Difração de Raios X
Óxido de Zinco/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Cadmium Compounds); 0 (Oxides); 0H3KWS8KJ3 (cadmium oxide); SOI2LOH54Z (Zinc Oxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171205
[St] Status:MEDLINE
[do] DOI:10.2147/IJN.S150405


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[PMID]:28452963
[Au] Autor:Yan X; Tong Z; Chen Y; Mo Y; Feng H; Li P; Qu X; Jin S
[Ad] Endereço:School of Material Science and Engineering, Beijing Institute of Technology, Beijing 100081, China. yanxt911218@163.com.
[Ti] Título:Bioresponsive Materials for Drug Delivery Based on Carboxymethyl Chitosan/Poly(γ-Glutamic Acid) Composite Microparticles.
[So] Source:Mar Drugs;15(5), 2017 Apr 28.
[Is] ISSN:1660-3397
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Carboxymethyl chitosan (CMCS) microparticles are a potential candidate for hemostatic wound dressing. However, its low swelling property limits its hemostatic performance. Poly(γ-glutamic acid) (PGA) is a natural polymer with excellent hydrophilicity. In the current study, a novel CMCS/PGA composite microparticles with a dual-network structure was prepared by the emulsification/internal gelation method. The structure and thermal stability of the composite were determined by Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The effects of preparation conditions on the swelling behavior of the composite were investigated. The results indicate that the swelling property of CMCS/PGA composite microparticles is pH sensitive. Levofloxacin (LFX) was immobilized in the composite microparticles as a model drug to evaluate the drug delivery performance of the composite. The release kinetics of LFX from the composite microparticles with different structures was determined. The results suggest that the CMCS/PGA composite microparticles are an excellent candidate carrier for drug delivery.
[Mh] Termos MeSH primário: Quitosana/análogos & derivados
Ácido Poliglutâmico/análogos & derivados
[Mh] Termos MeSH secundário: Quitosana/química
Portadores de Fármacos/química
Sistemas de Liberação de Medicamentos/métodos
Cinética
Espectroscopia Fotoeletrônica/métodos
Ácido Poliglutâmico/química
Polímeros/química
Espectroscopia de Infravermelho com Transformada de Fourier/métodos
Termogravimetria/métodos
Difração de Raios X/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Drug Carriers); 0 (Polymers); 0 (carboxymethyl-chitosan); 0 (poly(gamma-glutamic acid)); 25513-46-6 (Polyglutamic Acid); 9012-76-4 (Chitosan)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180228
[Lr] Data última revisão:
180228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE


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[PMID]:29264594
[Au] Autor:Hernández-Sánchez D; Villabona-Leal G; Saucedo-Orozco I; Bracamonte V; Pérez E; Bittencourt C; Quintana M
[Ad] Endereço:Instituto de Física, Universidad Autónoma de San Luis Potosí, Manuel Nava 6, Zona Universitaria, San Luis Potosí SLP 78290, Mexico. mildred@ifisica.uaslp.mx.
[Ti] Título:Stable graphene oxide-gold nanoparticle platforms for biosensing applications.
[So] Source:Phys Chem Chem Phys;20(3):1685-1692, 2018 Jan 17.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Graphene oxide-gold nanoparticle (AuNPs@GO) hybrids were fabricated in water dispersions of graphene oxide (GO) and Au precursor completely free of stabilizing agents by UV-light irradiation. Gold nanoparticle (AuNP) nucleation, growth, and stabilization mechanisms at the surface of GO are discussed on the basis of UV-Vis, Raman, IR, and X-Ray photo-spectroscopy studies. The analyses of AuNPs@GO hybrids by transmission electron microscopy (TEM), thermogravimetric (TGA) and electrochemical tests show that they exhibit outstanding chemical, thermal and electrochemical stabilities. Thus, AuNPs@GO biosensing platforms were fabricated for surface enhanced Raman spectroscopy (SERS) detection of crystal violet (CV), a SERS standard molecule, and in a different set of experiments, for flavin adenine dinucleotide (FAD), a flavoprotein coenzyme that plays an important role in many oxidoreductase and reversible redox conversions in biochemical reactions. AuNPs@GO hybrids synthesized by using UV light irradiation show exceptional stability and high intensification of the Raman signals showing that they have high potential for use as biomedical probes for the detection, monitoring, and diagnosis of medical diseases.
[Mh] Termos MeSH primário: Técnicas Biossensoriais/métodos
Ouro/química
Grafite/química
Nanopartículas Metálicas/química
[Mh] Termos MeSH secundário: Técnicas Eletroquímicas
Flavina-Adenina Dinucleotídeo/química
Microscopia Eletrônica de Transmissão
Oxirredução
Óxidos/química
Oxirredutases/química
Oxirredutases/metabolismo
Espectroscopia Fotoeletrônica
Espectrofotometria
Termogravimetria
Raios Ultravioleta
Água/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Oxides); 059QF0KO0R (Water); 146-14-5 (Flavin-Adenine Dinucleotide); 7440-57-5 (Gold); 7782-42-5 (Graphite); EC 1.- (Oxidoreductases)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171222
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp04817c


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[PMID]:29025648
[Au] Autor:Xue H; Chen Y; Liu X; Qian Q; Luo Y; Cui M; Chen Y; Yang DP; Chen Q
[Ad] Endereço:College of Environmental Science and Engineering, Fujian Normal University, Fujian Key Laboratory of Pollution Control & Resource Reuse, Fuzhou, China.
[Ti] Título:Visible light-assisted efficient degradation of dye pollutants with biomass-supported TiO hybrids.
[So] Source:Mater Sci Eng C Mater Biol Appl;82:197-203, 2018 Jan 01.
[Is] ISSN:1873-0191
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The objective of this work was to develop a novel organic-inorganic hybrid nanomaterial from agricultural biomass waste for environmental applications. The sugarcane bagasse (SB) supported TiO hybrids were firstly synthesized via a sol-gel method. A series of characterizations were carried out to reveal the structures and components of obtained hybrids. Due to organic-inorganic hybrid (OIH) effect and element doping, the SB-TiO hybrid can expand its optical absorbance ranging from ultraviolet to visible light. The optimal hybrid catalyst prepared with SB doping amount of 2g in 100mL titanic gel and calcined at 200°C was able to degradate 95.0% methyl orange (MO) in 5h under visible light. This study will pave a new and facile pathway for novel visible light driven photocatalysts based on TiO modified by agricultural biomass waste.
[Mh] Termos MeSH primário: Corantes/química
Luz
Titânio/química
Poluentes Químicos da Água/química
[Mh] Termos MeSH secundário: Compostos Azo/química
Biomassa
Catálise
Celulose/química
Géis/química
Nanoestruturas/química
Nanoestruturas/ultraestrutura
Espectroscopia Fotoeletrônica
Fotólise/efeitos da radiação
Espectroscopia de Infravermelho com Transformada de Fourier
Termogravimetria
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Azo Compounds); 0 (Coloring Agents); 0 (Gels); 0 (Water Pollutants, Chemical); 15FIX9V2JP (titanium dioxide); 6B4TC34456 (methyl orange); 9004-34-6 (Cellulose); 9006-97-7 (bagasse); D1JT611TNE (Titanium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180205
[Lr] Data última revisão:
180205
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171014
[St] Status:MEDLINE


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[PMID]:28464614
[Au] Autor:Skallberg A; Brommesson C; Uvdal K
[Ad] Endereço:Department of Physics, Chemistry and Biology (IFM), Division of Molecular Surface Physics and Nano Science, Linköping University, Linköping SE-581 83, Linköping, Sweden.
[Ti] Título:Imaging XPS and photoemission electron microscopy; surface chemical mapping and blood cell visualization.
[So] Source:Biointerphases;12(2):02C408, 2017 05 02.
[Is] ISSN:1559-4106
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Combined photoemission electron microscopy (PEEM) and imaging x-ray photoelectron spectroscopy (XPS), i.e., electron spectroscopy for chemical analysis in the nanoregion, has been used for surface characterization of bio-relevant and biological samples. In the first example, the authors prepared a gold patterned silicon substrate, stepwise surface modified by self-assembled monolayers followed by quantum dot (QDot) specific linking and investigated by means of work function mapping and elemental imaging in the submicrometer range. Spatially resolved core level images of C1s, V2p, and Y3d are obtained, which verify the selective thiol adsorption on the gold squares and specific binding of europium doped yttrium vanadate QDots on the self-assembled monolayer. The second example is platelet adhesion to Immunoglobulin G modified silicon surfaces, investigated by means of laterally resolved PEEM. Images of platelets clearly show activated cells with a morphology change including an enlarged surface area and elongated pseudopodia, with a lateral resolution of 140 nm. In the last example, neutrophils were allowed to attach to plain silicon surfaces and investigated by means of PEEM and imaging XPS. Here, the cells show a round shaped morphology, as expected. Threshold imaging with work function contrast is used to localize the area of interest, followed by elemental specific mapping on cells in the submicrometer region. Chemical shifts of C1s in photoemission are used to distinguish vital parts of the cell structure. The strong C1s (C-C) signal is achieved from the region of the cell membrane, i.e., high density of phospholipids, while C1s (C-N) and C1s (C-O) signals are obtained from the core of the cell, in good agreement with the presence of cytoplasm and deoxyribonucleic acid containing cell nucleus. The combination of PEEM and imaging XPS is shown here as a tool to deliver new insight into biological samples, i.e., a rapid sample overview is obtained based on low energy secondary electrons with work function contrast, followed by detailed studies in the narrow mode for elemental compositions based on photoemission. This study illustrates the strength of combined PEEM and XPS in the imaging mode on cell studies.
[Mh] Termos MeSH primário: Núcleo Celular/metabolismo
Núcleo Celular/ultraestrutura
Leucócitos/metabolismo
Leucócitos/ultraestrutura
Microscopia Eletrônica
Espectroscopia Fotoeletrônica
[Mh] Termos MeSH secundário: Seres Humanos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180201
[Lr] Data última revisão:
180201
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1116/1.4982644


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[PMID]:29337992
[Au] Autor:Emran KM; Al-Harbi AK
[Ad] Endereço:Chemistry Department, College of Science, Taibah University, Al-Madinah Al-Monawarah, Saudi Arabia.
[Ti] Título:Outstanding resistance and passivation behaviour of new Fe-Co metal-metal glassy alloys in alkaline media.
[So] Source:PLoS One;13(1):e0187567, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The electrochemical behavior of the oxide layers on two metal-metal glassy alloys, Fe78Co9Cr10Mo2Al1 (VX9)and Fe49Co49V2 (VX50) (at.%), were studied using electrochemical techniques including electrochemical frequency modulation (EFM), electrochemical impedance spectroscopy (EIS) and cyclic polarization (CP) measurements. The morphology and composition of the alloy surfaces were investigated using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The corrosion rate and surface roughness of both alloys increased as the concentration of NaOH in aqueous solution was raised. The presence of some protective elements in the composition of the alloys led to the formation of a spontaneous passive layer on the alloy surface. The higher resistance values of both alloys were associated with the magnitude of the dielectric properties of the passive films formed on their surfaces. Both alloys are classified as having outstanding resistance to corrosion, which results from the formation of a passive film that acts as an efficient barrier to corrosion in alkaline solution.
[Mh] Termos MeSH primário: Álcalis/química
Ligas/química
Cobalto/química
Vidro
Ferro/química
[Mh] Termos MeSH secundário: Corrosão
Microscopia de Força Atômica
Microscopia Eletrônica de Varredura
Espectroscopia Fotoeletrônica
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alkalies); 0 (Alloys); 3G0H8C9362 (Cobalt); E1UOL152H7 (Iron)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180129
[Lr] Data última revisão:
180129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180117
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0187567


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[PMID]:29102865
[Au] Autor:Fang L; Wu B; Chan JKM; Lo IMC
[Ad] Endereço:Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China.
[Ti] Título:Lanthanum oxide nanorods for enhanced phosphate removal from sewage: A response surface methodology study.
[So] Source:Chemosphere;192:209-216, 2018 Feb.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Lanthanum-based adsorbents are ideal candidates for phosphate removal because of their excellent affinity to phosphate. However, their application in the removal of trace-levels of phosphate from sewage is still unsatisfactory due to the limited adsorption capacity and inadequate optimization of the operational parameters. To overcome these drawbacks, we have developed a novel lanthanum hydroxide (LH), using a facile precipitation and hydrothermal process that involves a nanorod-like structure with the lengths ranging from 124 to 1700 nm, depending on the La/OH molar ratio. The phosphate adsorption capacity of the developed LH is up to 170.1 mg-P g in synthetic water, while a slightly lower adsorption capacity of 111.1 mg-P g is observed in a sewage sample. A polynominal model consisting of three variables (i.e. dosage, reaction time and initial phosphate concentration) for predicting efficiency of phosphate removal has been successfully developed using a face-centred central composite design (CCD)-based methodology. The results also suggest a strong interactive effect of the dosage with the phosphate concentration, and reaction time, which can significantly affect the optimization of the phosphate removal by LH. Both X-ray photoelectron spectroscopy and X-ray diffraction studies indicate that the inner sphere complexation of phosphate with LH is probably the major mechanism governing phosphate removal.
[Mh] Termos MeSH primário: Lantânio/química
Fosfatos/química
Esgotos/química
Poluentes Químicos da Água/química
Purificação da Água/métodos
[Mh] Termos MeSH secundário: Adsorção
Nanotubos
Espectroscopia Fotoeletrônica
Água/química
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Phosphates); 0 (Sewage); 0 (Water Pollutants, Chemical); 059QF0KO0R (Water); 39377-54-3 (lanthanum hydroxide); 6I3K30563S (Lanthanum)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180130
[Lr] Data última revisão:
180130
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171106
[St] Status:MEDLINE


  8 / 3596 MEDLINE  
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[PMID]:29261701
[Au] Autor:Singletary M; Hagerty S; Muramoto S; Daniels Y; MacCrehan WA; Stan G; Lau JW; Pustovyy O; Globa L; Morrison EE; Sorokulova I; Vodyanoy V
[Ad] Endereço:Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, Alabama, United States of America.
[Ti] Título:PEGylation of zinc nanoparticles amplifies their ability to enhance olfactory responses to odorant.
[So] Source:PLoS One;12(12):e0189273, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Olfactory responses are intensely enhanced with the addition of endogenous and engineered primarily-elemental small zinc nanoparticles (NPs). With aging, oxidation of these Zn nanoparticles eliminated the observed enhancement. The design of a polyethylene glycol coating to meet storage requirements of engineered zinc nanoparticles is evaluated to achieve maximal olfactory benefit. The zinc nanoparticles were covered with 1000 g/mol or 400 g/mol molecular weight polyethylene glycol (PEG). Non-PEGylated and PEGylated zinc nanoparticles were tested by electroolfactogram with isolated rat olfactory epithelium and odorant responses evoked by the mixture of eugenol, ethyl butyrate and (±) carvone after storage at 278 K (5 oC), 303 K (30 oC) and 323 K (50 oC). The particles were analyzed by atomic force microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and laser Doppler velocimetry. Our data indicate that stored ZnPEG400 nanoparticles maintain physiologically-consistent olfactory enhancement for over 300 days. These engineered Nanoparticles support future applications in olfactory research, sensitive detection, and medicine.
[Mh] Termos MeSH primário: Nanopartículas Metálicas/química
Odorantes
Mucosa Olfatória/efeitos dos fármacos
Polietilenoglicóis/química
Zinco/química
[Mh] Termos MeSH secundário: Microscopia de Força Atômica
Microscopia Eletrônica de Transmissão
Espectroscopia Fotoeletrônica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
30IQX730WE (Polyethylene Glycols); J41CSQ7QDS (Zinc)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180116
[Lr] Data última revisão:
180116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171221
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0189273


  9 / 3596 MEDLINE  
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[PMID]:29253012
[Au] Autor:Vongsvivut J; Truong VK; Al Kobaisi M; Maclaughlin S; Tobin MJ; Crawford RJ; Ivanova EP
[Ad] Endereço:Infrared Microspectroscopy (IRM) Beamline, Australian Synchrotron, Clayton, Victoria, Australia.
[Ti] Título:Synchrotron macro ATR-FTIR microspectroscopic analysis of silica nanoparticle-embedded polyester coated steel surfaces subjected to prolonged UV and humidity exposure.
[So] Source:PLoS One;12(12):e0188345, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Surface modification of polymers and paints is a popular and effective way to enhance the properties of these materials. This can be achieved by introducing a thin coating that preserves the bulk properties of the material, while protecting it from environmental exposure. Suitable materials for such coating technologies are inorganic oxides, such as alumina, titania and silica; however, the fate of these materials during long-term environmental exposure is an open question. In this study, polymer coatings that had been enhanced with the addition of silica nanoparticles (SiO2NPs) and subsequently subjected to environmental exposure, were characterized both before and after the exposure to determine any structural changes resulting from the exposure. High-resolution synchrotron macro ATR-FTIR microspectroscopy and surface topographic techniques, including optical profilometry and atomic force microscopy (AFM), were used to determine the long-term effect of the environment on these dual protection layers after 3 years of exposure to tropical and sub-tropical climates in Singapore and Queensland (Australia). Principal component analysis (PCA) based on the synchrotron macro ATR-FTIR spectral data revealed that, for the 9% (w/w) SiO2NP/polymer coating, a clear discrimination was observed between the control group (no environmental exposure) and those samples subjected to three years of environmental exposure in both Singapore and Queensland. The PCA loading plots indicated that, over the three year exposure period, a major change occurred in the triazine ring vibration in the melamine resins. This can be attributed to the triazine ring being very sensitive to hydrolysis under the high humidity conditions in tropical/sub-tropical environments. This work provides the first direct molecular evidence, acquired using a high-resolution mapping technique, of the climate-induced chemical evolution of a polyester coating. The observed changes in the surface topography of the coating are consistent with the changes in chemical composition.
[Mh] Termos MeSH primário: Materiais Revestidos Biocompatíveis/química
Umidade
Microespectrofotometria
Nanopartículas/química
Poliésteres/química
Dióxido de Silício/química
Aço/química
Síncrotrons
[Mh] Termos MeSH secundário: Meio Ambiente
Espectroscopia Fotoeletrônica
Análise de Componente Principal
Espectroscopia de Infravermelho com Transformada de Fourier
Análise Espectral Raman
Raios Ultravioleta
Água/química
Molhabilidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Coated Materials, Biocompatible); 0 (Polyesters); 059QF0KO0R (Water); 12597-69-2 (Steel); 7631-86-9 (Silicon Dioxide)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180108
[Lr] Data última revisão:
180108
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0188345


  10 / 3596 MEDLINE  
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[PMID]:28465106
[Au] Autor:Santini GC; Potrich C; Lunelli L; Vanzetti L; Marasso SL; Cocuzza M; Pirri FC; Pederzolli C
[Ad] Endereço:Fondazione Bruno Kessler, Laboratory of Biomolecular Sequence and Structure Analysis for Health, Via Sommarive 18, 38123, Povo, Trento, Italy.
[Ti] Título:miRNA purification with an optimized PDMS microdevice: Toward the direct purification of low abundant circulating biomarkers.
[So] Source:Biophys Chem;229:142-150, 2017 10.
[Is] ISSN:1873-4200
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:A reliable clinical assay based on circulating microRNAs (miRNAs) as biomarkers is highly required. Microdevices offer an attractive solution as a fast and inexpensive way of concentrating these biomarkers from a low sample volume. A previously developed polydimethylsiloxane (PDMS) microdevice able to purify and detect circulating miRNAs was here optimized. The optimization of the morphological and chemical surface properties by nanopatterning and functionalization is presented. Surfaces were firstly characterized by atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), fluorescamine assay and s-SDTB (sulphosuccinimidyl-4-o-(4,4-dimethoxytrityl) butyrate) assay and subsequently tested for their capacity to adsorb a fluorescent miRNA. From our analysis, modification of surface charge with 0.1% APTMS ((3-Aminopropyl)trimethoxysilane) and 0.9% PEG-s (2-[Methoxy-(polyethyleneoxy)propyl]trimethoxysilane) performed at 60°C for 10min was identified as the best purification condition. Our optimized microdevice integrated with real-time PCR detection, was demonstrated to selectively purify both synthetic and natural circulating miRNAs with a sensitivity of 0.01pM.
[Mh] Termos MeSH primário: Biomarcadores/sangue
Dimetilpolisiloxanos/química
MicroRNAs/isolamento & purificação
Técnicas Analíticas Microfluídicas/métodos
[Mh] Termos MeSH secundário: Corantes Fluorescentes/química
Seres Humanos
Isocianatos/química
MicroRNAs/sangue
MicroRNAs/química
Técnicas Analíticas Microfluídicas/instrumentação
Microscopia de Força Atômica
Espectroscopia Fotoeletrônica
Reação em Cadeia da Polimerase em Tempo Real
Silanos/química
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (3-isocyanatopropyl trimethoxysilane); 0 (Biomarkers); 0 (Dimethylpolysiloxanes); 0 (Fluorescent Dyes); 0 (Isocyanates); 0 (MicroRNAs); 0 (Silanes); 63148-62-9 (baysilon)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171213
[Lr] Data última revisão:
171213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE



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