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Mostrando postagens com marcador Nanopartículas. Mostrar todas as postagens
Mostrando postagens com marcador Nanopartículas. Mostrar todas as postagens

quarta-feira, 30 de março de 2011

Chemists' Biosensor May Improve Food, Water Safety and Cancer Detection

ScienceDaily (Mar. 29, 2011) — A nanotechnology-based biosensor being developed by Kansas State University researchers may allow early detection of both cancer cells and pathogens, leading to increased food safety and reduced health risks.

Lateef Syed, doctoral student in chemistry, Hyderabad, India, is developing the biosensor with Jun Li, associate professor of chemistry. Their research focuses on E. coli, but Syed said the same technology could also detect other kinds of pathogens, such as salmonella and viruses.

"Kansas is a leading state in meat production and the poultry industry," he said. "Any outbreak of pathogens in these industries causes huge financial losses and a lot of health risks. We want to prevent these outbreaks by detecting pathogens at an early stage."

Syed's recent research poster, "Dielectrophoretic Capture of E. coli at Nanoelectrode Arrays," was named a winner at the recent Capitol Graduate Research Summit in Topeka. An article on this work has been accepted for publication in the scientific journal Electrophoresis.

For more than three and a half years, Syed's research has focused on developing nanotechnology-based biosensors for pathogen detection and cancer biomarker detection. He began the research as a doctoral student under the direction of Li, who has researched nanotechnology for 15 years.

The project is a continuation of work that Li performed at the NASA Ames Research Center in California, where he spent seven years developing nanotechnology. While working in California, Li came up with the idea of developing a small chip to capture and detect pathogens.

When Li arrived at K-State in 2007 he continued the biosensor research with Syed. Together they are working on developing biosensors for cancer diagnosis and pathogen detection. To develop these biosensors, the team uses carbon nanofibers, or CNFs, because they can form an array of tiny electrodes that is even smaller than bacteria and viruses. When these microbial particles are captured at the electrode surface, an electric signal can be detected.

"A goal is to integrate this technology into a hand-held electronic device for pathogen detection so that we can use this device for in-line monitoring of water quality or food quality at industrial processing sites," Syed said. "We have some preliminary results that indicate this technology is feasible, and I'm quite happy about that."

"We're still working with the company and trying to eventually deliver this as a product to feed the market for water quality monitoring," Li said. "You don't want people to drink contaminated water and get sick before you can do something. This research can be very helpful in the future as it can be applied in the very early stages before an outbreak spreads.

"Nanotechnology is a diverse field, and includes such biosensor devices that we can develop in this lab at the university," he said.

segunda-feira, 6 de dezembro de 2010

Cientistas usam canela para criar nanopartículas saudáveis

Pesquisadores usam a especiaria para substituir compostos mais agressivos na produção de nanopartículas de ouro


Editora Globo
Nanopartículas de ouro, partes bem menores que nossas células, são usadas com sucesso em cosméticos e remédios para diagnosticar e tratar câncer. Mas o processo para a fabricação dessas partículas minúsculas envolve outros produtos químicos perigosos e tóxicos. Pesquisadores da Universidade do Missouri, no entanto, substituiram com sucesso os químicos nocivos pela canela, um produto natural e que não agride o corpo.
O processo tradicional para obtenção de nanopartículas leva produtos químicos prejudiciais ao ambiente e tóxicos para o organismo. Por isso, a especiaria representa uma alternativa natural para o procedimento. Os cientistas, liderados pelo professor de radiologia da universidade Kattesh Katti, misturaram sais de ouro à canela e depois acrescentaram água para sintetizar as nanopartículas.

Os pesquisadores descobriram que, durante a formação das nanopartículas, a canela liberava seus princípios ativos – ou fitoquímicos – , que quando eram misturados ao ouro conseguiam penetrar nas células cancerígenas e atacá-las ou servir de marcador para que exames possam identificá-las. "Está claro que a canela e outras espécies, como ervas, folhas e sementes servirão como reservatório de fitoquímicos e têm a capacidade de converter metais em nanopartículas”, diz Katti em um anúncio da universidade.
Katti é um dos pioneiros a desenvolver a nanotecnologia "verde, processo que não requer eletricidade e não utiliza agentes tóxicos aos organismos vivos. "Estamos criando tecnologia útil e totalmente nova", disse o professor.