29 resultados para NANOTECHNOLOGY

em Scielo Saúde Pública - SP


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Abstract: The field of nanotechnology involves an array of different areas of expertize with the application of innovative products in Medicine, Engineering, and to a less extent to Veterinary Medicine. In our opinion, more research is needed, in special to Animal Parasitology, to develop state of the art products to solve old problems. Livestock, pets and wildlife may benefit from products in nanoscale, such as vaccines, target recombinant proteins, or new drug candidates. Thus, we want to give some food for thought to drive scientific programs into nanotechnology, creating a safer environment to animals and humans

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Nanoscience and nanotechnology are new frontiers of this century. Their application to the agriculture and food sectors is relatively recent compared with their use in drug delivery and pharmaceuticals. Smart delivery of nutrients, bioseparation of proteins, rapid sampling of biological and chemical contaminants, and nanoencapsulation of nutraceuticals are some of the emerging topics of nanotechnology for food and agriculture. In this review, some applications of nanotechnology in agro-food sector are discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Given the increasing use of nanotechnology in food production and packaging, its acceptance was evaluated in Temuco, Chile, and different consumer segments were identified. Different brands of sunflower oil were used at different prices as a case study. A structured questionnaire was applied to 400 supermarket shoppers. It was determined that brand was more important than nanotechnology application in packaging and food, and more important than price. The consumers preferred an average priced oil with a manufacturer's brand with nanoparticles to reduce cholesterol, and packaging with nanoparticles to increase the shelf life of the product and to prevent the growth of microorganisms. Three consumer segments were distinguished by the cluster analysis. The largest segment (44%) preferred the oil without nanotechnology. The second (35.2%) preferred the oil with nanotechnology in the food and the packaging, and the greatest preference was for packaging with nanoparticles extension in the shelf life of the product. The third segment (20.8%) had similar behavior, but it showed greater preference for the oil with nanoparticles that reduced cholesterol and for the packaging that prevented the growth of bacteria and viruses. The segments differed in terms of their satisfaction with food-related life and lifestyle. It was found that over 50% of the participants preferred oil with nanotechnology applications.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The microbial synthesis of nanoparticles is a green chemistry approach that combines nanotechnology and microbial biotechnology. The aim of this study was to obtain silver nanoparticles (SNPs) using aqueous extract from the filamentous fungus Fusarium oxysporum as an alternative to chemical procedures and to evaluate its antifungal activity. SNPs production increased in a concentration-dependent way up to 1 mM silver nitrate until 30 days of reaction. Monodispersed and spherical SNPs were predominantly produced. After 60 days, it was possible to observe degenerated SNPs with in additional needle morphology. The SNPs showed a high antifungal activity against Candida and Cryptococcus , with minimum inhibitory concentration values ≤ 1.68 µg/mL for both genera. Morphological alterations of Cryptococcus neoformans treated with SNPs were observed such as disruption of the cell wall and cytoplasmic membrane and lost of the cytoplasm content. This work revealed that SNPs can be easily produced by F. oxysporum aqueous extracts and may be a feasible, low-cost, environmentally friendly method for generating stable and uniformly sized SNPs. Finally, we have demonstrated that these SNPs are active against pathogenic fungi, such as Candida and Cryptococcus .

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Supramolecular chemistry is expected to keep a high developing pace in the next years, giving support to the advancement of molecular devices and nanotechnology. In this sense, porphyrins and their analogues should play a significant role as a consequence of their catalytic, electrocatalytic, photochemical and photoelectrochemical properties. In this review we focused on our own strategy based on coordination chemistry for the design and build-up of supermolecules and supramolecular structures constituted by polynuclear porphyrins and metalloporphyrins. Included are also their properties and potential applications.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

An overview of the properties of carbon nanotubes is presented as a function of the structural characteristics and of the method of synthesis of these novel advanced materials. Emphasis is given to the catalytic decomposition of hydrocarbons over metal-supported catalysts and also the role of the support in obtaining homogeneous carbon nanotubes in high yelds is discussed. Some potential and real applications of carbon nanotubes are presented in a perspective view.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Nanotechnology can be viewed as a powerful tool, capable of shaping the chemistry of atoms and molecules, converting them into exciting nanosized and nanostructured materials, devices and machines. However, in pursuing this task, an exceptional ability is required to deal with complex inter- and multidisciplinary approaches, as imposed by the nanoscale. A new research organization framework, capable of promoting cooperative interactions in many complementary areas, including the industries, is demanded. In this sense, an interesting example are the nanotechnology networks and millenium institutes recently created in Brazil. The highlights and weakness of such cooperative research networks are discussed, in addition to relevant nanotechnology themes focusing on the special needs and resources from the developing nations.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A new white pigment made out of nano-structured non-crystalline aluminum phosphate was recently launched as an industrial product. Pigment opacifying properties are not intrinsic to aluminum phosphate but they arise as the result of a rare hollow particle nano-structure. This is in turn derived from the core-and-shell structure of amorphous aluminum phosphate precipitated under well-defined conditions. The new pigment is a product of the often neglected chemistry of non-crystalline ionic solids that can probably be a rich source of new successful products. The text describes a short account of the R&D activities, from the initial ideas to the present.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This review article describes the properties and the main applications of the glicol[n]urils. These compounds are cavitands made of n glycolurilic units arranged in circles, giving rise to extremely symmetric toroidal molecules. The cucurbit[n]urils create this way variable-sized hydrophobic cavities and the glycolurilic carbonyles delimit two portals on these cavities, slightly narrower than their internal radii. Their structure, physical and chemical properties favor the formation of inclusion compounds, and turn them into important building blocks for supramolecular chemistry and nanotechnology.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Chemical industry underwent a significant upturn in the past few years. In Brazil, the position of this industry has been continuously strengthened as the second largest industrial sector. Current circumstances are discussed, especially the need for increased innovation, the impacts of nanotechnology, biotechnology and information technologies. Some misconceptions on the Brazilian chemical industry are criticized and recent improvements are described, including those related to environmental protection, to conclude that its prospects are very good, considering both the availability of basic raw materials (oil, natural gas, agribusiness products and minerals), the growing demand and increased competitiveness.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Brazilian science is evolving rapidly and steadly in the last 10 years, reaching the 15º place in the international ranking. Research in nanotechnology is following a similar way generating new scientific and technological knowledge in several frontiers but specially in the interfaces of two or more areas, where Chemistry is consolidating itself as a central science. In this context, the supramolecular approach is a very promissing one because it allows the build-up of a chemical inteligence using all the sistematized knowledge for the design and development of new nanomaterials and products. The great challenge of Chemistry is not decrease the dimensionality of the materials but instead find ways to increase the dimensionality and structural complexity keeping strict control on the interactions between the components, in order to generate materials with new properties and functionalities. Unfortunately, the current vigorous advancement of scientific research has not been followed by the transformation of such know-how into patents and produts. Therefore much efforts should be devoted to build a national science and technology program, joining all the segments of the society involved in the technological development (university, institutes of technological research, industry and government) in order to promote the furtherance of the Brazilian technological base. Only in this way it is possible to evolve to a technological society capable to transform the scientific knowledge into wealthy, thus sustaining the socioeconomic development of the country.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Cyclodextrins (CDs) are cyclic oligosaccharides comprised of six or more glucose units connected by alpha-1,4 bonds. They have hydrophobic cavities with a hydrophilic exterior, and are versatile receptors for a variety of substrates. This ability allows them to be applied in many fields, as distinct as supramolecular chemistry, nanotechnology, pharmaceuticals, green chemistry, agrochemicals, analytical chemistry, toiletries, foods, and cosmetics. This review summarizes several aspects related to the physico-chemical properties of CDs and discusses their potential applications illustrated by recent examples. The prospects for their use in several areas are also described.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The objectives of this essay are to describe the development of nanoscience and nanotechnology (N&N) in Brazil. The analysis shows that Brazilian research in N&N is considered satisfactory and, although under other denominations, dates from at least 20 years. Innovation is still less satisfactory and there are different points of views on the issue. However, there is already a tendency towards the promotion of innovation in nanotechnology in the country. Scientists and the industrial sector have been showing interest in partnerships and some scientific policies stimulate this articulation between academy and companies.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The natural rubber is a strategic material which can not be replaced by synthetic rubber in many technological applications. Brazil is a rubber importer, but new techniques of cultivation, breeding and diversification of producing species can reverse this situation. One of the best ways to add value to this commodity is nanotechnology. The production of nanocomposites is already a reality and shows that the sustainable use of this natural resource can lead to new products and boost the national agribusiness setting labor-qualified in the field.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Each day, Earth's finite resources are being depleted for energy, for material goods, for transportation, for housing, and for drugs. As we evolve scientifically and technologically, and as the population of the world rapidly approaches 7 billion and beyond, among the many issues with which we are faced is the continued availability of drugs for future global health care. Medicinal agents are primarily derived from two sources, synthetic and natural, or in some cases, as semi-synthetic compounds, a mixture of the two. For the developed world, efforts have been initiated to make drug production "greener", with milder reagents, shorter reaction times, and more efficient processing, thereby using less energy, and reactions which are more atom efficient, and generate fewer by-products. However, most of the world's population uses plants, in either crude or extract form, for their primary health care. There is relatively little discussion as yet, about the long term effects of the current, non-sustainable harvesting methods for medicinal plants from the wild, which are depleting these critical resources without concurrent initiatives to commercialize their cultivation. To meet future public health care needs, a paradigm shift is required in order to adopt new approaches using contemporary technology which will result in drugs being regarded as a sustainable commodity, irrespective of their source. In this presentation, several approaches to enhancing and sustaining the availability of drugs, both synthetic and natural, will be discussed, including the use of vegetables as chemical reagents, and the deployment of integrated strategies involving information systems, biotechnology, nanotechnology, and detection techniques for the development of medicinal plants with enhanced levels of bioactive agents.