Base de dados : MEDLINE
Pesquisa : E05.196.712.726 [Categoria DeCS]
Referências encontradas : 59119 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 5912 ir para página                         

  1 / 59119 MEDLINE  
              next record last record
seleciona
para imprimir
Fotocópia
[PMID]:29292410
[Au] Autor:Mehl A; Bosch G; Fischer C; Ender A
[Ti] Título:In vivo tooth-color measurement with a new 3D intraoral scanning system in comparison to conventional digital and visual color determination methods.
[So] Source:Int J Comput Dent;20(4):343-361, 2017.
[Is] ISSN:1463-4201
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:STATEMENT OF PROBLEM: Three-dimensional (3D) intraoral scanning systems allow for the simultaneous acquisition of 3D information about tooth surfaces and a photorealistic view of the patient's tooth colors. AIM: The goal of this study was the in vivo comparison of a new 3D scanner with a color acquisition mode and conventional visual and digital color measurements. MATERIALS AND METHODS: The colors of 40 teeth of 20 patients were evaluated in seven ways: 1) By dentists using the Vita 3D-Master; 2) By dental technicians using the Vita 3D-Master; 3) With the 3Shape Trios device; 4) With the Vita Easyshade device; 5) With the Vita Easyshade Advance device; 6) With the SpectroShade device; and 7) With the SpectroShade Micro device. Digital measurements of Groups 3 to 7 were repeated three times for each tooth. For all groups, both the CIE Lab values and the Vita 3D-Master values were recorded. The repeatability and relative accuracy of the Vita 3D-Master values were analyzed statistically using Pearson's chi-squared test (α < 0.05). ΔE values were calculated from the CIE Lab values, which served as a basis for performing multidimensional scaling (MDS) and evaluating differences between the groups using the one-way ANOVA with post hoc Tamhane's test (α < 0.05). RESULTS: The results of the ΔE values showed that clinically relevant differences between the evaluation by dentists, dental technicians, and the intraoral scanning device (3Shape) are negligible. The intraoral 3D scanning device (Group 3) and the digital systems (Groups 4 to 7) did not differ significantly in the repeatability of color shade management. The SpectroShade Micro (Group 7) had significantly better relative accuracy than the other devices. CONCLUSIONS: The results demonstrate that intraoral scanning systems can be used to measure both tooth color and tooth surface in 3D. CLINICAL IMPLICATIONS: Intraoral optical scanning devices allow for the acquisition of accurate 3D surface data. Tooth color can be evaluated simultaneously and can be used to determine the color of restorations without requiring additional conventional color-measurement methods.
[Mh] Termos MeSH primário: Cor
Planejamento de Prótese Dentária
Pigmentação em Prótese/instrumentação
Dente/anatomia & histologia
[Mh] Termos MeSH secundário: Colorimetria/instrumentação
Seres Humanos
Fotografia
Espectrofotometria
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180228
[Lr] Data última revisão:
180228
[Sb] Subgrupo de revista:D
[Da] Data de entrada para processamento:180103
[St] Status:MEDLINE


  2 / 59119 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29376153
[Au] Autor:Das R; Rajender G; Giri PK
[Ad] Endereço:Department of Physics, Indian Institute of Technology Guwahati, Guwahati - 781039, India. giri@iitg.ernet.in.
[Ti] Título:Anomalous fluorescence enhancement and fluorescence quenching of graphene quantum dots by single walled carbon nanotubes.
[So] Source:Phys Chem Chem Phys;20(6):4527-4537, 2018 Feb 07.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:We explore the mechanism of the fluorescence enhancement and fluorescence quenching effect of single walled carbon nanotubes (SWCNTs) on highly fluorescent graphene quantum dots (GQDs) over a wide range of concentrations of SWCNTs. At very low concentrations of SWCNTs, the fluorescence intensity of the GQDs is enhanced, while at higher concentrations, systematic quenching of fluorescence is observed. The nature of the Stern-Volmer plot for the latter case was found to be non-linear indicating a combined effect of dynamic and static quenching. The contribution of the dynamic quenching component was assessed through the fluorescence lifetime measurements. The contribution of static quenching is confirmed from the red shift of the fluorescence spectra of the GQDs after addition of SWCNTs. The fluorescence intensity is first enhanced at very low concentration due to improved dispersion and higher absorption by GQDs, while at higher concentration, the fluorescence of GQDs is quenched due to the complex formation and associated reduction of the radiative sites of the GQDs, which is confirmed from time-resolved fluorescence measurements. Laser confocal microscopy imaging provides direct evidence of the enhancement and quenching of fluorescence at low and high concentrations of SWCNTs, respectively. This study provides an important insight into tuning the fluorescence of GQDs and understanding the interaction between GQDs and different CNTs, which is important for bio-imaging and drug delivery applications.
[Mh] Termos MeSH primário: Grafite/química
Nanotubos de Carbono/química
Pontos Quânticos/química
[Mh] Termos MeSH secundário: Microscopia Confocal
Espectrofotometria
Análise Espectral Raman
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nanotubes, Carbon); 7782-42-5 (Graphite)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180130
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp06994d


  3 / 59119 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29188253
[Au] Autor:Takaya T; Anan M; Iwata K
[Ad] Endereço:Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan. tomohisa.takaya@gakushuin.ac.jp koichi.iwata@gakushuin.ac.jp.
[Ti] Título:Vibrational relaxation dynamics of ß-carotene and its derivatives with substituents on terminal rings in electronically excited states as studied by femtosecond time-resolved stimulated Raman spectroscopy in the near-IR region.
[So] Source:Phys Chem Chem Phys;20(5):3320-3327, 2018 Jan 31.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The electronic and vibrational relaxation of carotenoids is one of the key processes in the protection of living cells as well as in the functions of proteins involved in photosynthesis. In this study, the electronic and vibrational relaxation dynamics of ß-carotene and its derivatives with substituents on the terminal rings is investigated using femtosecond time-resolved absorption and stimulated Raman spectroscopy in the near-IR region. The carbonyl substituent induces low-frequency shifts of the steady-state and transient absorption bands, decreases of the excited-state lifetimes and the acceleration of vibrational relaxation of the conjugated main chain, whereas the hydroxyl substituent only slightly affects them. The effects of the carbonyl group in the electronic relaxation dynamics are explained well by the lengthening of effective conjugation by the carbonyl group through a partial conjugation between the main chain and the terminal ring. Time-resolved near-IR stimulated Raman spectroscopy demonstrates the significance of the peripheral substitution with the carbonyl group for the vibrational energy relaxation of ß-carotene derivatives in the lowest excited singlet state.
[Mh] Termos MeSH primário: beta Caroteno/análogos & derivados
[Mh] Termos MeSH secundário: Acetona/química
Cantaxantina/química
Espectrofotometria
Análise Espectral Raman
Xantofilas/química
Zeaxantinas/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Xanthophylls); 0 (Zeaxanthins); 01YAE03M7J (beta Carotene); 1364PS73AF (Acetone); 4C3C6403MU (Canthaxanthin); 8XPW32PR7I (astaxanthine)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171201
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp06343a


  4 / 59119 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29413989
[Au] Autor:Marques RA; Gomes AOCV; de Brito MV; Dos Santos ALP; da Silva GS; de Lima LB; Nunes FM; de Mattos MC; de Oliveira FCE; do Ó Pessoa C; de Moraes MO; de Fátima Â; Franco LL; Silva MM; Dantas MDA; Santos JCC; Figueiredo IM; da Silva-Júnior EF; de Aquino TM; de Araújo-Júnior JX; de Oliveira MCF; Leslie Gunatilaka AA
[Ad] Endereço:Department of Organic and Inorganic Chemistry, Federal University of Ceará, Fortaleza, Ceará, Brazil; Northern Educational Union - UNINORTE, Rio Branco, Acre, Brazil.
[Ti] Título:Annonalide and derivatives: Semisynthesis, cytotoxic activities and studies on interaction of annonalide with DNA.
[So] Source:J Photochem Photobiol B;179:156-166, 2018 Feb.
[Is] ISSN:1873-2682
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:The cytotoxic activity of the pimarane diterpene annonalide (1) and nine of its semisynthetic derivatives (2-10) was investigated against the human tumor cell lines HL-60 (leukemia), PC-3 (prostate adenocarcinoma), HepG2 (hepatocellular carcinoma), SF-295 (glioblastoma) and HCT-116 (colon cancer), and normal mouse fibroblast (L929) cells. The preparation of 2-10 involved derivatization of the side chain of 1 at C-13. Except for 2, all derivatives are being reported for the first time. Most of the tested compounds presented IC s below 4.0 µM, being considered potential antitumor agents. The structures of all new compounds were elucidated by spectroscopic analyses including 2D NMR and HRMS. Additionally, the interaction of annonalide (1) with ctDNA was evaluated using spectroscopic techniques, and the formation of a supramolecular complex with the macromolecule was confirmed. Competition assays with fluorescent probes (Hoechst and ethidium bromide) and theoretical studies confirmed that 1 interacts preferentially via DNA intercalation with stoichiometric ratio of 1:1 (1:ctDNA). The ΔG value was calculated as -28.24 kJ mol , and indicated that the interaction process occurs spontaneously. Docking studies revealed that van der Walls is the most important interaction in 1-DNA and EB-DNA complexes, and that both ligands (1 and EB) interact with the same DNA residues (DA6, DA17 and DT19).
[Mh] Termos MeSH primário: Ciclo-Octanos/química
DNA/química
Cetonas/química
[Mh] Termos MeSH secundário: Animais
Sítios de Ligação
Bovinos
Linhagem Celular Tumoral
Sobrevivência Celular
Ciclo-Octanos/síntese química
Ciclo-Octanos/toxicidade
DNA/metabolismo
Ensaios de Seleção de Medicamentos Antitumorais
Seres Humanos
Cetonas/síntese química
Cetonas/toxicidade
Simulação de Acoplamento Molecular
Conformação de Ácido Nucleico
Espectrofotometria
Eletricidade Estática
Termodinâmica
Temperatura de Transição
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cyclooctanes); 0 (Ketones); 502-49-8 (cyclooctanone); 9007-49-2 (DNA); 91080-16-9 (calf thymus DNA)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180208
[St] Status:MEDLINE


  5 / 59119 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29289927
[Au] Autor:Rajeswari A; Jackcina Stobel Christy E; Pius A
[Ad] Endereço:Department of Chemistry, The Gandhigram Rural Institute - Deemed University, Gandhigram, Dindigul 624 302, Tamil Nadu, India.
[Ti] Título:New insight of hybrid membrane to degrade Congo red and Reactive yellow under sunlight.
[So] Source:J Photochem Photobiol B;179:7-17, 2018 Feb.
[Is] ISSN:1873-2682
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:A study was carried out to investigate the degradation of organic contaminants (Congo red and Reactive yellow - 105) using cellulose acetate - polystyrene (CA-PS) membrane with and without ZnO impregnation. Scanning electron microscope (SEM), electron dispersive analysis of X-rays (EDAX), Fourier transform infrared spectrometer (FTIR), atomic force microscope (AFM) and thermogravimeric analysis (TG-DTA) analysis were carried out to characterize bare and ZnO impregnated CA-PS membranes. Membrane efficiency was also tested for pure water flux and antifouling performance. The modified membrane showed almost 85% water flux recovery. Blending of ZnO nanoparticles to CA-PS matrix could decrease membrane fouling and increase permeation quality of the membrane with above 90% of photocatalytic degradation efficiency for dyes. The rate of degradation of dyes was observed using UV-Vis spectrometer. Reusability of CA-PS-ZnO membrane was studied and no significant change was noted in the degradation efficiency until fourth cycle. Langmuir-Hinshelwood kinetic model well describes the photo degradation capacity and the degradation of dyes CR and RY - 105 exhibited pseudo-first order kinetics. The regression coefficient (R) of CR and RY - 105 found to be 0.99. The novelty of the prepared CA-PS-ZnO membrane is that it has better efficiency and high thermal stability than our previously reported material. Therefore, ZnO impregnated CA-PS membrane had proved to be an innovative alternative for the degradation of CR and RY - 105 dyes.
[Mh] Termos MeSH primário: Corantes/química
Vermelho Congo/química
Nanocompostos/química
Fotólise/efeitos da radiação
Luz Solar
Óxido de Zinco/química
[Mh] Termos MeSH secundário: Catálise
Celulose/análogos & derivados
Celulose/química
Microscopia de Força Atômica
Microscopia Eletrônica de Varredura
Poliestirenos/química
Espectrofotometria
Espectroscopia de Infravermelho com Transformada de Fourier
Termogravimetria
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Coloring Agents); 0 (Polystyrenes); 3J2P07GVB6 (acetylcellulose); 3U05FHG59S (Congo Red); 9004-34-6 (Cellulose); SOI2LOH54Z (Zinc Oxide)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180101
[St] Status:MEDLINE


  6 / 59119 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[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


  7 / 59119 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29272851
[Au] Autor:Zaheer Z
[Ad] Endereço:Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21413, Saudi Arabia. Electronic address: zzkhan@kau.edu.sa.
[Ti] Título:Biogenic synthesis, optical, catalytic, and in vitro antimicrobial potential of Ag-nanoparticles prepared using Palm date fruit extract.
[So] Source:J Photochem Photobiol B;178:584-592, 2018 Jan.
[Is] ISSN:1873-2682
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Silver nanoparticles (AgNPs) have been synthesized via green route using an aqueous extract of Palm date fruit pericarp extract. The appearance of the yellow color and the surface resonance plasmon (SRP) band at around 400-450nm in UV-Visible spectroscopy initially reveals the formation of AgNPs. The particle size, crystalline nature, and size distribution was confirmed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED) ring patterns, energy dispersive X-ray spectroscopy (EDX), dynamic light scattering (DLS) techniques. The particles size ranged ca. 3nm to 30nm and are spherical in shape. The microbial activity of biogenic AgNPs was tested on clinical multiple drug resistance Staphylococcus aureus, Escherichia coli and Candida albicans reference strain. Zones of inhibition growth increases with [AgNPs]. The results suggest that the particle tested in this study certainly mediate the inhibition of bacterial and fungus growth. To overcome the serious problems related to environment like discharge of hazardous chemicals to water bodies, AgNPs have been found to be very important in the catalytic degradation of 4-nitrophenol. The rate of degradation strongly depends on the sun light exposure. Based on the chemical and kinetic studies, an attempt has been made to elucidate the mechanism of AgNPs formation.
[Mh] Termos MeSH primário: Anti-Infecciosos/síntese química
Nanopartículas Metálicas/química
Phoeniceae/química
Prata/química
[Mh] Termos MeSH secundário: Anti-Infecciosos/química
Anti-Infecciosos/farmacologia
Candida albicans/efeitos dos fármacos
Catálise
Difusão Dinâmica da Luz
Escherichia coli/efeitos dos fármacos
Frutas/química
Frutas/metabolismo
Química Verde
Nanopartículas Metálicas/toxicidade
Microscopia Eletrônica de Varredura
Nitrofenóis/química
Tamanho da Partícula
Phoeniceae/metabolismo
Fotólise/efeitos da radiação
Extratos Vegetais/química
Espectrometria por Raios X
Espectrofotometria
Staphylococcus aureus/efeitos dos fármacos
Luz Solar
Ressonância de Plasmônio de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Infective Agents); 0 (Nitrophenols); 0 (Plant Extracts); 3M4G523W1G (Silver); Y92ZL45L4R (4-nitrophenol)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171223
[St] Status:MEDLINE


  8 / 59119 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29247926
[Au] Autor:Gitelson A; Solovchenko A
[Ad] Endereço:Faculty of Civil and Environmental Engineering, Israel Institute of Technology, Technion City, Haifa, Israel. Electronic address: ganatoly@technion.ac.il.
[Ti] Título:Non-invasive quantification of foliar pigments: Possibilities and limitations of reflectance- and absorbance-based approaches.
[So] Source:J Photochem Photobiol B;178:537-544, 2018 Jan.
[Is] ISSN:1873-2682
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Established reflectance-based approaches for estimation of foliar pigment contents assume close relationship between leaf absorbance and reflectance. Complex organization and high pigment content of leaves may lead to violation of the essential assumptions under Kubleka-Munk theory relating reflectance and absorbance. We compared relationships of absorbance and reciprocal reflectance vs. pigment content in leaves collected across species, developmental stages and physiological states. As a result, limitations of reflectance-based spectroscopy for pigment quantification were revealed. We deduced in situ absorbance of foliar chlorophylls, carotenoids, and flavonoids (including red-colored anthocyanins) and introduced a concept of specific spectral response of the optical properties to each pigment group. Quantitative criteria of spectral range selection for the absorbance- and reflectance-based techniques yielding effect of each pigment on the background of other pigment absorption were suggested and validated. We argue that absorbance- and reflectance-based approaches to pigment estimation complement each other and can be used synergistically in advanced models for accurate estimating foliar pigments. The study provides a deeper insight into interception of light by photosynthetic and photoprotective pigments as function of physiological condition and developmental stage, which is important for plant biology as well as knowledge-driven selection of spectral bands for noninvasive pigment estimation models.
[Mh] Termos MeSH primário: Pigmentos Biológicos/química
Plantas/química
[Mh] Termos MeSH secundário: Antocianinas/química
Carotenoides/química
Clorofila/química
Flavonoides/química
Folhas de Planta/química
Folhas de Planta/metabolismo
Plantas/metabolismo
Espectrofotometria
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anthocyanins); 0 (Flavonoids); 0 (Pigments, Biological); 1406-65-1 (Chlorophyll); 36-88-4 (Carotenoids)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171217
[St] Status:MEDLINE


  9 / 59119 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29175604
[Au] Autor:González-Ballesteros N; Rodríguez-González JB; Rodríguez-Argüelles MC
[Ad] Endereço:Departamento de Química Inorgánica, Universidade de Vigo, 36310 Vigo, Spain.
[Ti] Título:Harnessing the wine dregs: An approach towards a more sustainable synthesis of gold and silver nanoparticles.
[So] Source:J Photochem Photobiol B;178:302-309, 2018 Jan.
[Is] ISSN:1873-2682
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:In recent years, the management of food waste processing has emerged as a major concern. One such type of food waste, grape pomace, has been shown to be a great source of bioactive compounds which might be used for more environmentally - friendly processes for the synthesis of nanomaterials. In this study, grape pomace of Vitis vinifera has been used for the obtainment of an aqueous extract. Firstly, the reducing activity, total phenolic content and DPPH scavenging activity of the aqueous extract were determined. Then, the aqueous extract was used for the synthesis of gold and silver nanoparticles. The formation of spherical and stable nanoparticles with mean diameters of 35.3±5.2nm for Au@GP and 42.9±6.4nm for Ag@GP was confirmed by UV-vis spectroscopy and transmission electron microscopy. Furthermore, the functional group of biomolecules present in grape pomace extract, Au@GP and Ag@GP, were characterized by Fourier transform infrared spectroscopy prior to and after the synthesis, in order to obtain information about the biomolecules involved in the reducing and stabilization process. This study is the first to deal with the use of Vitis vinifera grape pomace in obtaining gold and silver nanoparticles through an eco-friendly, quick, one-pot synthetic route.
[Mh] Termos MeSH primário: Ouro/química
Nanopartículas Metálicas/química
Prata/química
Vitis/química
[Mh] Termos MeSH secundário: Química Verde
Microscopia Eletrônica de Transmissão
Tamanho da Partícula
Extratos Vegetais/química
Espectrofotometria
Espectroscopia de Infravermelho com Transformada de Fourier
Vitis/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Plant Extracts); 3M4G523W1G (Silver); 7440-57-5 (Gold)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171128
[St] Status:MEDLINE


  10 / 59119 MEDLINE  
              first record previous record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28749499
[Au] Autor:Horbury MD; Quan WD; Flourat AL; Allais F; Stavros VG
[Ad] Endereço:Department of Chemistry, University of Warwick, Gibbet Hill, Coventry, CV4 7AL, UK. v.stavros@warwick.ac.uk.
[Ti] Título:Elucidating nuclear motions in a plant sunscreen during photoisomerization through solvent viscosity effects.
[So] Source:Phys Chem Chem Phys;19(31):21127-21131, 2017 Aug 09.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:We explore the effects of solvent viscosity on the trans-cis photoisomerization of sinapoyl malate, which is utilized as a sunscreen molecule in plants. Our results demonstrate that viscosity has a significant effect on the timescale for isomerization, providing insight into the nuclear motions involved. The ramifications of these findings are discussed with reference to sinapoyl malate's in vivo photoprotection properties.
[Mh] Termos MeSH primário: Malatos/química
Fenilpropionatos/química
Plantas/química
Solventes/química
Protetores Solares/química
[Mh] Termos MeSH secundário: Isomerismo
Plantas/metabolismo
Espectrofotometria
Raios Ultravioleta
Viscosidade/efeitos da radiação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (2-O-sinapoylmalate); 0 (Malates); 0 (Phenylpropionates); 0 (Solvents); 0 (Sunscreening Agents)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170728
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp04070a



página 1 de 5912 ir para página                         
   


Refinar a pesquisa
  Base de dados : MEDLINE Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde