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1.
Curr Org Synth ; 20(1): 20-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35170414

RESUMO

Aza-boron-dipyrromethenes (Aza-BODIPYs) represent an important class of chromophores absorbing and emitting in the near-infrared (NIR) region. They have unique optical and electronic features and higher physiological and photo stability than other NIR dyes. Especially after the development of facile synthetic routes, Aza-BODIPYs have become indispensable fluors that can find various applications ranging from chemosensors, bioimaging, phototherapy, solar energy materials, photocatalysis, photon upconversion, lasers, and optoelectronics. Herein, we review Aza-BODIPY based fluorescent and colorimetric chemosensors. We show the potential and untapped toolbox of Aza-BODIPY based fluorescent and colorimetric chemosensors. Hence, we divide the fluorescent and colorimetric chemosensors and probes into five sections according to the target analytes. The first section begins with the chemosensors developed for pH. Next, we discuss Aza-BODIPY based ion sensors, including metal ions and anions. Finally, we present the chemosensors and probes concerning reactive oxygen (ROS) and nitrogen species (RNS) along with biologically relevant species in the last two sections. We believe that Aza-BODIPYs are still in their infancy, and they have a promising future for translation from the bench to real biomedical and materials science applications. After two decades of intensive research, it seems that there are many more to come in this already fertile field. Overall, we hope that future work will further expand the applications of Aza-BODIPY in many areas.


Assuntos
Eletrônica , Ciência dos Materiais
2.
Chemistry ; 29(5): e202202769, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36216778

RESUMO

Linearly-fused polyarenes are an important class of compounds with high relevance in materials science. While modifying the shape and size represents a common means to fine-tune their properties, the precise placement of heteroatoms is a strategy that is receiving an increasing deal of attention to overcome the intrinsic limitations of all-carbon structures. Thus, linearly-fused diphosphaarenes recently emerged as a novel family of molecules with striking optoelectronic properties and outstanding stability. However, the properties of diphosphaarenes are far from being benchmarked. Herein, we report the synthesis, phosphorus post-functionalization and properties of new diphosphapentaarene derivatives. We describe their synthetic limitations and unveil their potential for optoelectronic applications.


Assuntos
Carbono , Ciência dos Materiais , Fósforo
3.
Zhen Ci Yan Jiu ; 46(6): 515-7, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34190457

RESUMO

Combining the current development of material science and acupunctology, we propose a new concept of "acupuncture-material science" as the new branch of acupunctology. We also hold that this new branch may be in the future the important direction of acupuncture-moxibustion instrument innovation. The future carding and development of the connotations and epita-xial contents of this discipline, the classification, applied range, research and development of the materials, as well as the related standard formulation, etc. should be paid more attention and improved in order to make greater contribution to the inheritance and innovation of acupunctology in the new era.


Assuntos
Terapia por Acupuntura , Acupuntura , Moxibustão , Ciência dos Materiais , Pesquisa
4.
Nat Commun ; 11(1): 1449, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-32193375

RESUMO

Pollen's practically-indestructible shell structure has long inspired the biomimetic design of organic materials. However, there is limited understanding of how the mechanical, chemical, and adhesion properties of pollen are biologically controlled and whether strategies can be devised to manipulate pollen beyond natural performance limits. Here, we report a facile approach to transform pollen grains into soft microgel by remodeling pollen shells. Marked alterations to the pollen substructures led to environmental stimuli responsiveness, which reveal how the interplay of substructure-specific material properties dictates microgel swelling behavior. Our investigation of pollen grains from across the plant kingdom further showed that microgel formation occurs with tested pollen species from eudicot plants. Collectively, our experimental and computational results offer fundamental insights into how tuning pollen structure can cause dramatic alterations to material properties, and inspire future investigation into understanding how the material science of pollen might influence plant reproductive success.


Assuntos
Ciência dos Materiais , Microgéis/química , Pólen/química , Biomimética/métodos , Química Computacional , Epitopos/química , Epitopos/imunologia , Esterificação , Dureza , Hidrólise , Hidróxidos/química , Microscopia de Fluorescência , Pectinas/química , Pectinas/imunologia , Pólen/imunologia , Polinização/fisiologia , Compostos de Potássio/química , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Eur J Pharm Biopharm ; 141: 149-160, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31132400

RESUMO

The aim of this work was to investigate the relationship between formulation material properties, process parameters and process performance for the manufacturing of amorphous solid dispersions via hot-melt extrusion (HME) using experimentation coupled with process modeling. Specifically, we evaluated the impact of the matrix copovidone melt rheology with and without the addition of a plasticizing surfactant, polysorbate 80, while also varying the process parameters, barrel temperature and screw speed, and keeping fill volume constant. To correlate the process performance to a critical quality attribute, we used telmisartan as an indicator substance by processing at temperatures below its solubility temperature in the polymeric matrix. We observed a broader design space of HME processes for the plasticized formulation with respect to screw speed than for the copovidone-only matrix formulation. This observation was determined by the range of observed melt temperatures in the extruder, both measured and simulated. The reason was not primarily linked to a reduced shear-thinning behavior, characterized by the power law index, n, but instead more to an overall reduced melt viscosity during extrusion and zero-shear rate viscosity, η0, accordingly. We also found that the amount of residual crystallinity of telmisartan correlated with the simulated maximum melt temperature in the extruder barrel. This finding confirmed the applicability of the temperature-dependent API-matrix solubility phase diagram for HME to process development. Given the complex inter-dependent relationships between material properties, process and performance, process modeling combined with reduced laboratory experimentation was established as a holistic approach for the evaluation of Quality-by-Design-based HME process design spaces.


Assuntos
Polímeros/química , Povidona/química , Telmisartan/química , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Temperatura Alta , Ciência dos Materiais/métodos , Polissorbatos/química , Pirrolidinas/química , Reologia , Solubilidade/efeitos dos fármacos , Compostos de Vinila/química , Viscosidade/efeitos dos fármacos
6.
ACS Comb Sci ; 21(6): 437-444, 2019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-30939240

RESUMO

This is a report on the early years of combinatorial materials science and technology. High-throughput technologies (HTTs) are found in life- and materials-science laboratories. Although HTTs have long been the standard in life sciences in academia as well as in industry, HTTs in materials science have become the standard in industry but not in academia. In life science, successful drugs developed with HTTs have been reported, but there is no information on successful materials developed with HTTs that have made it to the market. Some initial development of HTTs in materials science is summarized, especially early applications of artificial intelligence. This outlook attempts to summarize the development of combinatorial materials sciences from the early years to today.


Assuntos
Ensaios de Triagem em Larga Escala , Ciência dos Materiais , Catálise , Avaliação Pré-Clínica de Medicamentos/história , Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/normas , Ensaios de Triagem em Larga Escala/história , Ensaios de Triagem em Larga Escala/métodos , Ensaios de Triagem em Larga Escala/normas , História do Século XX , História do Século XXI , Indústrias/história , Indústrias/métodos , Ciência dos Materiais/história , Ciência dos Materiais/métodos , Ciência dos Materiais/normas
7.
Belo Horizonte; s.n; 2018. 71 p. ilus, tab.
Tese em Inglês, Português | LILACS, BBO | ID: biblio-914053

RESUMO

Um dos maiores desafios atuais da ciência dos materiais dentários é a obtenção de união efetiva e durável às cerâmicas de alto conteúdo cristalino. O objetivo do presente estudo foi avaliar a resistência de união, energia de superfície e tipos de fratura de dois sistemas cerâmicos após diferentes formas de tratamento de superfície associada à aplicação do plasma em pressão atmosférica. Para o estudo foram obtidas quarenta placas de zircônia (12 mm x 5 mm x 1,5 mm) de dois tipos de cerâmicas zircônia (E.max ZirCad e Calypso), polidas e limpas por ultrassom durante 5 minutos. Divididas aleatoriamente em 2 grupos de acordo com o sistema cerâmico e 4 subgrupos (n=5) de acordo com o tratamento de superfície, (I) controle (primer), (II) jateamento com partículas micrométricas de alumina (Al2O3) + primer, (III) jateamento com partículas micrométricas de alumina (Al2O3) + plasma + primer, (IV) plasma + primer. Foram confeccionados cento e vinte cilindros de resina composta (Z100), utilizando matrizes cilíndricas (1,0 mm x 3,0 mm) cimentadas com cimento resinoso, Multilink N, sobre as placas de zircônia. Os espécimes foram armazenados em água destilada durante 24 horas a 37° C, depois testados para microcisalhamento em máquina de teste Shimadzu EZ a 1,0 mm/min. Os dados obtidos foram submetidos à análise estatística para comparação entre os grupos E.max e Calypso em relação à resistência à união (força/área ­ MPa), ângulo de contato e os tipos de fratura. Os dados foram analisados pelos testes ANOVA One-Way e Kruskal-Wallis para resistência de união (p=0,003) e (p=0,005) e ângulo de contato (p<0,001) e (p<0,001). Não houve diferença significativa para os dados de fratura (p=0,145), pelo teste quiquadrado, com predomínio de fraturas mistas. Os valores de resistência de união das cerâmicas Y-TZP apresentaram maiores valores quando o plasma foi associado ao jateamento com óxido de alumínio e/ou primer e a aplicação somente do plasma não superou os valores alcançados pelas outras formas de tratamento da superfície. Essa associação resultou em menores valores dos ângulos de contato. Houve maior frequência de fraturas mistas quando realizado somente o tratamento com óxido de alumínio e quando em associação com o plasma.(AU)


One of the major challenges today in the science of dental materials is the achievement of effective and durable bonding to ceramics with high crystalline content. The objective of the present study was to evaluate the efficacy of plasma at atmospheric pressure in the adhesion of ceramic zirconia through the bond strength, surface energy and type of fracture of two ceramic systems after different forms of surface treatment associated with the application of plasma at atmospheric pressure. For the study forty zirconia plates (12 mm x 5 mm x 1.5 mm) were obtained from two zirconia ceramics (E.max ZirCad and Calypso), polished and cleaned by ultrasound for 5 minutes. Randomly divided into 2 groups according to the ceramic system and 4 subgroups (n = 5) according to the surface treatment, control (primer), primer + blasting with micrometric alumina (Al2O3) particles, primer + blasting with micrometric particles of alumina (Al2O3) + plasma, primer + plasma. One hundred and twenty cylinders of composite resin (Z-100) were made using cylindrical matrices (1.0 mm x 3.0 mm) cemented on the zirconia plates. The specimens were stored in distilled water for 24 hours at 37°C, then tested for microshear on a Shimadzu EZ test machine at 0.5 mm / min. The obtained data were submitted to statistical analysis for comparison between the E.max and Calypso groups in relation to the bond strength (strength / area - Mpa), contact angle and fracture types. The data were analyzed by ANOVA One-Way and Kruskal-Wallis tests for bond strength (p=0.003) and (p=0.005) and contact angle (p<0.001) and (p<0.001). There was no significant difference for the fracture data (p = 0.145), by the chi-square test, with a predominance of mixed fractures. The bond strength values of the Y-TZP ceramics showed higher values when the plasma was associated with blasting with aluminum oxide and / or primer and the application of only the plasma did not exceed the values reached by the other forms of surface treatment. This association resulted in lower values of contact angles. It is a higher frequency of mixed fractures when only aluminum oxide treatment is performed and when it is associated with plasma.(AU)


Assuntos
Pressão Atmosférica , Cerâmica , Materiais Dentários , Ciência dos Materiais , Fenômenos Químicos , Plasma , Cimentos de Resina , Zircônio , Óxido de Alumínio , Ligas Metalo-Cerâmicas
8.
Rio de Janeiro; s.n; 2009. 84 p. ilus, tab, graf.
Tese em Português | LILACS, BBO | ID: lil-525059

RESUMO

Objetivo: O objetivo do trabalho foi caracterizar e comparar sistemas cerâmicos aluminizados infiltrados por vidro, por meio de difração por RX, microscopia eletrônica de varredura e resistência à flexão uniaxial em três pontos. Os sistemas cerâmicos utilizados foram: (IC)- In-Ceram Alumina (VITA), (VC)- Vitro-Ceram (Angelus) e (AG)- Alglass (Celmat). A fase cristalina de cada material foi identificada por meio de difração por RX. Dez espécimes em forma de barra (25X4X1,2±0,1) de cada material foram produzidos seguindo as instruções do fabricante de acordo com a ISO 6872. Os espécimes foram levados em uma máquina de ensaio universal para avaliação da resistência à flexão em três pontos, com carga de 500Kgf, velocidade de 0,5mm/min e distância entre os apoios de 15mm. Os dados foram submetidos a análise estatística ANOVA (p<0,01). Os espécimes fraturados foram observados no MEV em diversas condições: superfície jateada, superfície polida, superfície fraturada e alumina sem infiltração. Resultados: Foi identificada uma segunda fase cristalina de zircônia dopada com Ítrio no VC. Os valores médios de resistência à flexão foram (MPa): VC (483±38,3)= IC (456,6±29,4) > AG(263,8±37,8) (nível de 1% de significância). A micromorfologia dos sistemas apresentou características bem distintas, com diferenças em relação ao tamanho e distribuição das partículas de alumina e capacidade de molhamento do vidro de infiltração. A análise da fratura demonstrou comportamento semelhante contornando a maioria dos grãos de alumina e atravessando outros...


Objective: The purpose of this study was to characterize and compare glass-infused alumina-based ceramic systems by using X-Ray diffraction, scanning electron microscopy (SEM) and flexural strength with a three-point bending test. The ceramic systems used were: (IC)- In-Ceram Alumina (VITA), (VC)- Vitro-Ceram (Angelus) and (AG)- Alglass (Celmat). The crystalline phase of each material was identified through X-Ray diffraction. Ten bar specimens (25X4X1,2±0.1) of each material were produced following the manufacturer's instructions according to ISO 6872. The specimens were taken to a universal testing machine to evaluate flexural strength with a three-point bending test, with a constant load of 500Kgf, crosshead speed of 0,5mm/min and a 15mm distance between supports. The data was submitted to ANOVA (p<0.01) statistical analysis. The fractured specimens underwent SEM analysis in different conditions: sandblasted surface, polished surface, fractured surface and alumina without infiltration. Results: a second crystalline phase of yttrium-stabilized zirconia was identified in VC. Mean values of flexural strength were (MPa): VC (483±38.3)= IC (456,6±29.4) > AG(263,8±37.8). The micro morphology presented distinct characteristics for each system, with differences in relation to size and distribution of the alumina particles, and the ability of glass infiltration. Fracture analysis showed similar behavior contouring most alumina particles and though others...


Assuntos
Óxido de Alumínio , Cerâmica , Materiais Dentários , Análise de Variância , Ciência dos Materiais , Microscopia Eletrônica de Varredura
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