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terça-feira, 18 de agosto de 2015

UK Report Assesses Workplace Exposure and Control Measures During the Manufacture and Handling of Engineered Nanomaterials


The United Kingdom’s Health and Safety Laboratory (HSL) of the Health and Safety Executive (HSE) prepared a report entitled Summary of work undertaken to assess workplace exposure and control measures during the manufacture and handling of engineered nanomaterials.  
The report notes that HSE and HSL attempted to identify and engage with companies that manufactured or used nanomaterials, but only four volunteered to take part in this project.  The report cautions that the observations represent a limited data set, and need to be understood in this context and not overgeneralized.  
The objectives were to visit companies to assess exposure to airborne nanomaterials during their manufacture, handling, and use, and to assess the effectiveness of the controls used to reduce exposure to nanomaterials.  
The key findings include:

  • An increased understanding of some of the tasks and activities undertaken during the manufacturing, handling, or use of nanomaterials and the potential for exposure to airborne nanomaterials;
  • Existing good hygiene control practices can be used to reduce exposure to airborne nanomaterials;
  • An exposure monitoring strategy suited to small businesses to monitor emission of airborne nanomaterials was evaluated and found to be practical and cost effective;
  • The company Control of Substances Hazardous to Health (COSHH) assessments were not specific to nanomaterials and all of the assessments reviewed could have been improved;
  • An effective risk management assessment strategy could include a combination of a simple exposure monitoring approach and an occupational hygiene assessment of the process and the controls; and
  • There is not enough evidence yet to propose a measurement methodology that should be used to underpin separate specific occupational exposure limits (OEL) for nanomaterials if these were to be proposed.

ABC e SBPC publicam manifesto sobre Nanociências e Nanoengenharia

A Academia Brasileira de Ciências (ABC) e a Sociedade Brasileira para o Progresso da Ciência (SBPC) publicaram  manifesto em resposta aos relatos dos Projetos de Lei 5133/13 e 6741/13, ambos de autoria do Deputado Federal José Sarney Filho. Leia a íntegra da Carta:





Carta da ABC em resposta aos relatos dos Projetos de Lei 5133/13 e 6741/13

Todas as tentativas de regulação da nanotecnologia, nos diferentes países, têm sido prejudicadas pela confusão sobre a sua definição. Há muitas definições e várias se referem ao estudo e controle de fenômenos e materiais em escalas de comprimento inferior a 100 nm. 
A definição utilizada pela National Nanotechnology Initiative (NNI) dos Estados Unidos estabelece que "nanotecnologia é a compreensão e o controle da matéria em dimensões na faixa 1-100 nm, onde fenômenos únicos levam a novas aplicações. Abrangendo ciência, engenharia e tecnologia na nanoescala (1-100nm), a nanotecnologia envolve imagear, mensurar, modelar e manipular a matéria nesta escala de tamanhos." 
A faixa preconizada neste definição abrange os tamanhos de moléculas e de pequenas partículas formadas por átomos e moléculas pequenas, tendo portanto uma enorme abrangência.
Nenhuma definição estabelece que um nanomaterial tenha uma composição específica. Por isso, todas elas abrigam uma variedade enorme de tipos de nanomateriais, incluindo as nanopartículas orgânicas e biodegradáveis utilizadas nas áreas da medicina, cosmética e indústria alimentícia, que são muitas vezes constituídas de óleo, água e alguns outros componentes igualmente inócuos. Por exemplo, o leite materno e a maionese.
Existem ainda as nanopartículas e nanoestruturas metálicas e de carbono, utilizadas nas indústrias de catalisadores, de tintas e no tratamento de água pelos municípios, produção de caixas de som, remediação ambiental, indústria aeroespacial e em centenas de outros exemplos. Um terceiro tipo são os nanotubos e outros materiais constituídos basicamente por átomos de carbono, com aplicações potenciais na fabricação de LEDs, células fotovoltaicas, circuitos eletrônicos, baterias e usadas industrialmente na fabricação de telas touchscreen. Os computadores atuais são alimentados por microprocessadores que usam chips com estruturas que medem de 14 a 22 nanometros, que são importantes resultados práticos da nanotecnologia. 
A indústria farmacêutica já produz medicamentos baseados em nanomateriais para o tratamento de câncer e outras doenças, com resultados dramaticamente positivos e poucos efeitos colaterais. 
Um exemplo notável é o medicamento Abraxane para tratamento de câncer de mama metastático, aprovado pela FDA e autorizado para uso em dezenas de países. Este produto incorpora nanopartículas de albumina. Há também um produto para o tratamento de anemia grave, utilizando nanopartículas de ferro. Estes e outros resultados já obtidos com os nanomateriais em medicina estimulam uma grande atividade de pesquisa.
Os exemplos acima mostram que nanomateriais são estruturas fabricadas pelo homem, algumas delas há séculos, ao lado de outras produzidas pela natureza desde sempre, como o caso do leite materno, de bactérias sintetizadoras, de nanopartículas de óxidos de ferro e da ferritina, que armazena ferro no sangue de mamíferos. Em outras palavras, os nanomateriais não são uma invenção recente do homem e existem na natureza, desde há muito. Entretanto, os fabricantes de vitrais da Idade Média não sabiam que estavam produzindo nanomateriais, nem os formuladores de medicamentos no século 20.
A nanotecnologia tornou-se uma política prioritária do governo brasileiro no início da década de 2000, em função do seu enorme impacto na inovação. Foi tratada como área estratégica nos diversos programas estruturantes: o Plano de Ação em Ciência, Tecnologia e Inovação (PACTI 2007-2010), a Política de Desenvolvimento Produtivo (PDP), a Estratégia Nacional para Ciência, Tecnologia e Inovação (ENCTI 2012-2015) e o Plano Brasil Maior
Essas políticas fomentaram investimentos governamentais significativos com a criação de 17 redes temáticas, 16 INCTs e mais de 50 laboratórios nacionais com atuação na área de Nanociências e Nanotecnologia. O programa de subvenção econômica para empresas na área de nanotecnologia beneficiou cerca de 50 empresas entre 2006 e 2010 em áreas diversas como energia, biotecnologia, defesa e segurança pública, saúde, bens de capital, TICS, sociais entre outras. 
Embora ainda tímida em comparação com outros países, o fortalecimento da área veio com o lançamento da iniciativa brasileira de nanotecnologia (IBN) em 2013, que é um marco para a área em termos de política de Estado, pois tem sua governança envolvendo dez ministérios. A iniciativa estruturou o Programa SisNANO com a criação de uma rede de oito laboratórios estratégicos e 18 associados que, usando a nanotecnologia como plataforma para a inovação, se propõe a oferecer respostas para desafios econômicos e sociais do país, a fortalecer a indústria, a criar empregos e, a longo prazo, a melhorar a qualidade de vida da população.
O país já começa a colher os frutos das políticas e dos investimentos em nanotecnologia. Os indicadores de desempenho do Brasil na área de nanotecnologia melhoram continuamente. Crescem a formação de recursos humanos, a produção científica, a criação de empresas start-ups e o lançamento de produtos no mercado. Destacam-se os produtos lançados no mercado na área cosmecêutica e os nanomateriais funcionais usados para remediação ambiental, incorporados em tecidos, em tintas, em plásticos e em sensores. Já contamos com 160 empresas, cerca de 6.000 estudantes e mais de 2.000 cientistas atuando em nanotecnologia e nanociência.
Como qualquer nova ou velha tecnologia, esta também tem riscos. Os seus riscos à saúde humana têm sido amplamente estudados, e os resultados mostram a inexistência de quaisquer riscos "nano-específicos", embora estes sejam frequentemente mencionados em publicações que não têm base científica.
O Brasil tem mostrado competência em nanotoxicologia com muita responsabilidade e participa de iniciativas internacionais de alto nível, que se apoiam na fronteira do conhecimento, como é o caso dos projetos Europeus Nanoreg, que é um consórcio que envolve não apenas a Europa, como também inúmeros outros países. Além disso são seis Redes de Pesquisa em Nanotoxicologia financiadas pelo Ministério da Ciência, Tecnologia e Inovação e laboratórios do SisNANO que estão se capacitando para obterem certificação.
A comunidade científica brasileira está atenta aos possíveis riscos e tem produzido subsídios para a elaboração prudente de marcos regulatórios da nanotecnologia. Por isso mesmo a comunidade científica se opõe à criação precipitada de leis cujo resultado será o engessamento, injustificado e mal fundamentado, de uma área que é uma grande janela de oportunidades para o país.
Para que as políticas nacionais sejam responsáveis, protegendo a saúde da população brasileira e o meio ambiente e, ao mesmo tempo, estimulem as iniciativas de desenvolvimento econômico e estratégico do Brasil, a Academia Brasileira de Ciências propõe à consideração dos Senhores Deputados:

1) A retirada de pauta dos projetos de lei 5133/13 e 6741/13, de autoria do Deputado Sarney Filho, nas comissões em que está tramitando;
2) A criação de um grupo de trabalho, no âmbito do Congresso, para o acompanhamento de iniciativas e políticas de regulação da nanotecnologia nos países desenvolvidos;
3) A definição de uma instância envolvendo o Legislativo e o Executivo, e quanto a este notadamente o MCTI, para a atualização e consolidação das informações existentes, fornecendo aos poderes da República elementos para a tomada das medidas que garantam ao Brasil o máximo aproveitamento das oportunidades econômicas e estratégicas da nanotecnologia e a máxima proteção contra qualquer risco que ela possa criar.

Grupo de Estudos sobre Nanociências e Nanoengenharia Academia Brasileira de Ciências

Fonte: ABC

segunda-feira, 17 de agosto de 2015

NanoFilter: Bug-killing book pages clean murky drinking water


By Jonathan Webb

A man leafing through the book
The next stage is to test the books in larger trials
 where they are used by local residents
A book with pages that can be torn out to filter drinking water has proved effective in its first field trials.
The "drinkable book" combines treated paper with printed information on how and why water should be filtered.
Its pages contain nanoparticles of silver or copper, which kill bacteria in the water as it passes through.
In trials at 25 contaminated water sources in South Africa, Ghana and Bangladesh, the paper successfully removed more than 99% of bacteria.
The resulting levels of contamination are similar to US tap water, the researchers say. Tiny amounts of silver or copper also leached into the water, but these were well below safety limits.
The results were presented at the 250th national meeting of the American Chemical Society in Boston, US.
Dr Teri Dankovich, a postdoctoral researcher at Carnegie Mellon University in Pittsburgh, developed and tested the technology for the book over several years, working at McGill University in Canada and then at the University of Virginia.
"It's directed towards communities in developing countries," Dr Dankovich said, noting that 663 million people around the world do not have access to clean drinking water.
"All you need to do is tear out a paper, put it in a simple filter holder and pour water into it from rivers, streams, wells etc and out comes clean water - and dead bacteria as well," she told BBC news.
The bugs absorb silver or copper ions - depending on the nanoparticles used - as they percolate through the page.
"Ions come off the surface of the nanoparticles, and those are absorbed by the microbes," Dr Dankovich explained.

According to her tests, one page can clean up to 100 litres of water. A book could filter one person's water supply for four years.
A page of the book, showing printed instructions
Instructions are printed on the book's pages, in English as well as the local language

Dr Dankovich had already tested the paper in the lab using artificially contaminated water. Success there led to the field trials which she conducted over the past two years, working with the charities Water is Life and iDE.
In these trials, the bacteria count in the water samples plummeted by well over 99% on average - and in most samples, it dropped to zero.
"Greater than 90% of the samples had basically no viable bacteria in them, after we filtered the water through the paper," Dr Dankovich said.
"It's really exciting to see that not only can this paper work in lab models, but it also has shown success with real water sources that people are using."
One location gave the paper a particularly tough challenge.
"There was one site where there was literally raw sewage being dumped into the stream, which had very high levels of bacteria.
"But we were really impressed with the performance of the paper; it was able to kill the bacteria almost completely in those samples. And they were pretty gross to start with, so we thought - if it can do this, it can probably do a lot."

More work to to

Dr Dankovich and her colleagues are hoping to step up production of the paper, which she and her students currently make by hand, and move on to trials in which local residents use the filters themselves.
"We need to get it into people's hands to see more of what the effects are going to be. There's only so much you can do when you're a scientist on your own."
For example, Dr Dankovich's work with iDE in Bangladesh has explored whether a filter, holding one of the book pages, could be fitted into a "kolshi" - the traditional water container used by many Bangladeshis.
Dr Daniele Lantagne, an environmental engineer at Tufts University, said the data from the trials showed promise.
"There's a lot of interest in developing new products for point-of-use water treatment," she told the BBC.
The "drinkable book" has now passed two key stages - showing that it works in the lab, and on real water sources.
Next, Dr Lantagne said, the team will need "a commercialisable, scalable product design" for a device that the pages slot into.
She also said that while the paper appears to kill bacteria successfully, it is unclear whether it would remove other disease-causing micro-organisms.
"I would want to see results for protozoa and viruses," she said.
A woman filtering water through a funnel
The team is investigating how to combine the
filter paper with kolshi water containers
 (the metal flasks in this photo)
"This is promising but it's not going to save the world tomorrow. They've completed an important step and there are more to go through."
Dr Kyle Doudrick studies sustainable water treatment at the University of Notre Dame in Indiana. He agreed that the book system would be especially powerful if it could also tackle non-bacterial infections, such as the tiny parasite cryptosporidium which recently caused a health scare in Lancashire.
He also said it would be important to make sure people understood how to use the filters - and how often to change them. But he was encouraged by the trial results.
"Overall, out of all the technologies that are available - ceramic filters, UV sterilisation and so on - this is a promising one, because it's cheap, and it's a catchy idea that people can get hold of and understand."

Fonte: BBC

domingo, 16 de agosto de 2015

Sediment dwelling creatures at risk from nanoparticles in common household products

Researchers from the University of Exeter highlight the risk that engineered nanoparticles released from masonry paint on exterior facades, and consumer products such as zinc oxide cream, could have on aquatic creatures.


Mud flats in Topsham, Devon
Textiles, paint, sunscreen, cosmetics and food additives are all increasingly containing metal-based nanoparticles that are engineered, rather than found naturally.
The review, published today in the journal Environmental Chemistry, highlights the risks posed to aquatic organisms when nanoparticles ‘transform’ on contact with water and as they pass from water to sediment and then into sediment dwelling organisms.
Sediments are important for the health of many aquatic ecosystems and are speculated to be a large potential sink for nanoparticles.
Richard Cross, lead author and postgraduate researcher from the College of Life and Environmental Sciences at the University of Exeter’s Biosciences department said: “We argue for the need to incorporate the transformations that engineered nanomaterials undergo as they pass from water bodies into sediments, as their form and nature will change as they do so. This is important to consider if we are to improve environmental realism in our experimental efforts and also better understand the long term effects of these materials in the environment.”
Professor Charles Tyler, of the College of Life and Environmental Sciences at the University of Exeter, added: “In the aquatic environment, it is known that many nanomaterials will end up in the sediment, so it makes sense to focus on this environmental compartment as a possible worst case scenario for exposures and effects in aquatic systems. This review serves to highlight what we need to consider when assessing the susceptibility of sediment dwelling organisms to nanomaterials.”
The study calls for more research into whether ‘marine snow’ - organic detritus that falls through layers of water – acts as a transport system for nanoparticles and closer examination of bioaccumulation and toxicity in sediment-dwelling species.
The study highlights a large knowledge gap and recommends further research into the factors that determine the fate of nanoparticles in aquatic systems.

Fonte: University of Exeter

ONU seleciona estudantes para Programa de Bolsas de Tecnologias de Nanossatélites

Serão selecionados até dois estudantes para o mestrado e até quatro para o doutorado. Prazo é dia 24 de janeiro de 2016.
Foto: NASA
Foto: NASA
O Escritório das Nações Unidas para Assuntos do Espaço Sideral (UNOOSA) e o Governo do Japão está selecionando estudantes de países em desenvolvimento e de nações não desenvolvidas na temática para um programa de bolsas de tecnologias de nano satélites.
Os nano satélites são satélites de baixo custo quje utilizam tecnologias acessíveis que estão se tornando cada vez mais capazes de realizar missões científicas. O Programa de Bolsas de Tecnologias de Nano Satélites foi criada para promover a engenharia espacial e ajudar a construir capacidades científicas nos países em desenvolvimento e nas nações que ainda não trabalham com o tema.
O programa irá fornecer amplas oportunidades de investigação para o desenvolvimento de sistemas de nano satélites através do uso do desenvolvimento de nano satélites e das instalações disponíveis no Instituto de Tecnologia de Kyushu (Kyutech), no Japão.
Entre os candidatos qualificados, até dois alunos serão escolhidos para o programa de Mestrado (duração de dois anos) e até quatro alunos para o programa de Doutorado (duração de três anos). Os candidatos selecionados receberão uma subvenção para cobrir mensalidades do programa e custos básicos.
As candidaturas para o Programa de Bolsas serão aceitas até 24 de janeiro. Todos os detalhes em http://bit.ly/1Wp3QQr
Fonte: ONU

Nanossatélite Serpens será levado a Estação Espacial na segunda-feira

Foto: Valdivino Jr/AEB –
 Modelo de engenharia do Serpens.

O satélite de pequeno porte Serpens, sigla do projeto Sistema Espacial para Realização de Pesquisa e Experimentos com Nanossatélites, criado pela Agência Espacial Brasileira (AEB), será levado para a Estação Espacial Internacional (ISS), na segunda-feira (17).

Desenvolvido por estudantes da Universidade de Brasília (UnB) em parceria com alunos de outras instituições de nível superior nacionais e internacionais, o cubsat nacional partirá do Centro Espacial de Tanegashima, no Japão, em direção à ISS, de onde será colocado em órbita em outubro.

Ele é o terceiro cubsat nacional a ser colocado no espaço, e testará conceitos simples do uso cubesat para o recebimento, armazenamento e retransmissão de mensagens por sistema de rádio.

O engenheiro mecatrônico e bolsista da AEB, Gabriel Figueiró explica que o projeto Serpens tem como foco principal fomentar a educação espacial do país. “Outro objetivo fundamental da missão é a capacitação de recursos humanos, fator primordial para o desenvolvimento e consolidação dos novos cursos de engenharia espacial brasileiros, requisito importante para o Programa Espacial Brasileiro”, afirma.

Ele ainda informa que um nanossatélite mede, basicamente, a partir de 10cm x 10cm x 10cm, pesando cerca de 1kg. O Serpens mede 10cm x 10cm x 30cm com quase 3kg de peso.

Participam do projeto as universidades federais do ABC (Ufabc), de Santa Catarina (UFSC), de Minas Gerais (UFMG) e o Instituto Federal Fluminense (IFF). Do exterior estão envolvidas, as universidades de Vigo, da Espanha, Sapienza Università di Roma (Itália) e as norte-americanas Morehead State University e California State Polytechnic University.

Segundo Figueiró, esta primeira missão do programa foi coordenada pela UnB, mas a proposta é que cada uma das instituições envolvidas coordene a produção, o lançamento e a missão dos próximos artefatos.


Fonte: AEB-Coordenação de Comunicação Social (CCS)

sábado, 8 de agosto de 2015

Nanopartículas contra o câncer


Projeto de parceria entre USP e IPT estuda formas de encapsulação polimérica para tratamento por hipertermia


O aluno de Bioengenharia da USP de São Carlos Caio José Perecin, em parceria com o IPT por meio do Programa Novos Talentos, está trabalhando no projeto de mestrado com o tema ‘Nanopartículas superparamagnéticas encapsuladas com polímeros para tratamento de câncer por hipertermia’. A ideia é que as nanoestruturas, aliadas à aplicação de um campo magnético alternado, promovam um aumento de temperatura na região afetada para gerar um efeito citotóxico nas células tumorais (ou seja, ‘matá-las’), já que essas são mais sensíveis ao calor do que as células sadias. 

Iniciado em fevereiro de 2014 no Programa de Pós-Graduação Interunidades da USP sob a orientação do professor Sérgio Yoshioka e co-orientação da pesquisadora Natalia Cerize, do Núcleo de Bionanomanufatura do IPT, o trabalho inova no tema da encapsulação das nanopartículas superparamagnéticas, empregando a tecnologia de secagem por nano spray dryer e a rota de síntese. “A ideia é desenvolver uma nanopartícula polimérica que tenha ação direcionada ao alvo (no caso, as células tumorais) e ao núcleo superparamagnético, para a geração de calor no local”, afirma Natalia. 

A nanopartícula estudada no IPT é composta por magnetita, um tipo de óxido de ferro que possui as propriedades magnéticas para gerar calor. Além de atuar como agente de hipertermia devido ao seu teor magnético, as nanopartículas do mineral também podem ajudar na veiculação de uma molécula terapêutica para uma região de interesse. Devido à sua composição, ela pode ser atraída por um campo magnético até uma região como um tumor, por exemplo.

“Elas também podem atuar como agente de contraste para a captura de imagens por ressonância magnética, que é uma forma de diagnóstico do câncer. Hoje em dia, há outros tipos de agentes de contraste usados para obter as imagens, mas as nanopartículas são uma opção interessante devido à sua reduzida toxicidade”, declara Perecin.
Trabalho inova no tema da encapsulação
das nanopartículas superparamagnéticas

A encapsulação polimérica utilizada no IPT é uma estratégia para estabilizar as nanopartículas, evitando a aglomeração da magnetita – o que poderia causar efeitos indesejados caso estivesse presente na corrente sanguínea – e contribuindo para que as partículas sejam absorvidas preferencialmente pelas células tumorais. A encapsulação é feita no Instituto usando o nano spray dryer, um dos únicos equipamentos no País. Perecin está testando diferentes tipos de polímeros para viabilizar uma alta eficiência de encapsulação e verificar a viabilidade para diminuir a aglomeração de material.

Um dos polímeros analisados pelo estudante é a maltodextrina, usada por jogadores de futebol e maratonistas, que auxilia na passagem por barreiras biológicas, usando um tensoativo que interage com as células endoteliais (que recobrem o interior dos vasos sanguíneos) e atravessa, por exemplo, a barreira hematoencefálica, já que um dos focos dos pesquisadores é o tratamento do gliobastoma (um tipo de câncer de cérebro).

Outro polímero utilizado foi o Eudragit, que pode ser utilizado para auxiliar no direcionamento das partículas até um câncer de intestino, por exemplo. E ainda foi utilizada uma matriz polimérica composta por Policaprolactona (PCL) e Pluronic, também já relatada na literatura com sucesso para tratamento de tumores cerebrais.

O projeto conta com apoio de oito profissionais ligados diretamente ao trabalho, de diversos laboratórios do IPT. Além da parceria com a unidade da USP em São Carlos, também há a ajuda do professor Valmir Chitta, do Instituto de Física da USP, que trabalha com magnetismo, e no IPT o pesquisador Adriano Marim de Oliveira, do Laboratório de Processos Químicos e Tecnologia de Particulas. 

Ainda em parceria com outros laboratórios do instituto, o trabalho conta com a ajuda das pesquisadoras Catia Fredericci, do Laboratório de Processos Metalúrgicos, e Patricia Leo, do Laboratório de Biotecnologia Industrial, que está fazendo testes nas nanopartículas para avaliação de citotoxicidade e avaliação em células neoplásicas de câncer de colo de útero e fígado para analisar como a partícula se comporta em diferentes meios.

É importante ressaltar que o trabalho dos pesquisadores estuda uma terapia alternativa para o tratamento do câncer, indicando a existência de um potencial que ainda não foi testado em animais ou humanos e ainda está em desenvolvimento. “É um desafio preparar nanopartículas que sejam biocompatíveis, consigam chegar até a região do tumor e matem seletivamente as células tumorais”, acrescenta Perecin.

“Hipertermia é uma terapia já utilizada e possui eficácia, mas o tipo de partícula usada para essa terapia é ainda um desafio. Se conseguirmos desenvolver um tipo de partícula nova, que possibilite maior desempenho terapêutico reduzindo efeitos colaterais, atingindo menos as células sadias e preferencialmente as tumorais, então teremos uma potencial tecnologia”, completa Natalia.

Como resultado do projeto de mestrado, algumas publicações foram realizadas. Caio participou do XXIV Congresso Brasileiro de Engenharia Biomédica (CBEB) em Uberlândia no ano passado, e já teve trabalhos aprovados para o XIV Encontro da Sociedade Brasileira de Pesquisa em Materiais (SBPMat) e para a Soft Magnetic Materials Conference (SMM 22), que ocorrerão em setembro no Rio de Janeiro e em São Paulo, respectivamente.

Fonte: IPT

Proving nanoparticles in sunscreen products


When a nanoparticle enters into plasma, a discontinuous
signal occurs. Signal intensity correlates to particle size.

© Fraunhofer IGB
Cosmetics increasingly contain nanoparticles. One especially sensitive issue is the use of the miniscule particles in cosmetics, since the consumer comes into direct contact with the products. Sunscreen lotions for example have nanoparticles of titanium oxide. They provide UV protection: like a film made of infinite tiny mirrors, they are applied to the skin and reflect UV rays. But these tiny particles are controversial. They can penetrate the skin if there is an injury, and trigger an inflammatory reaction. Its use in spray-on sunscreens is also problematic. Scientists fear that the particles could have a detrimental effect on the lungs when inhaled. Even the effect on the environment has not yet been adequately researched. Studies indicate that the titanium oxide which has seeped into public beaches through sunscreens can endanger environmental balance. Therefore, a labeling requirement has been in force since July 2013, based on an EU Directive on cosmetics and body care products. If nano-sized ingredients are used in a product, the manufacturer must make this fact clear by adding “nano-” to the listed ingredient name. Due to requirements imposed by the legislature, the need for analysis methods is huge.


Determining particle sizes down to the tiniest scale

Today’s electron microscope imaging processes, such as transmission-electron microscopy or scanning electron microscopy, are based on the properties of light dispersion. They are used to detect all particles present. They do not differentiate between a cell, a nanoparticle – or a piece of lint. These methods are ideally suited for the study of surface properties and shapes.

“The light diffusion process and microscopy are not selective enough for a lot of studies, including toxicological examinations,” says Gabriele Beck-Schwadorf, scientist at the Fraunhofer Institute for Interfacial Engineering and Thin Films IGB in Stuttgart. The group manager and her team have advanced and refined an existing measurement method in a way that allows them to determine titanium nanoparticles within complex media consisting of several different components that are highly sensitive and delicate. Researchers measure individual particles by single particle, inductively coupled plasma mass spectroscopy (or SP-ICP-MS). “With this method, I determine mass. Titanium has an atomic mass of 48 AMUs (atomic mass units). If I set the spectrometer to that, then I can target the measurement of titanium,” explains Katrin Sommer, food chemist at IGB.

With particle measurement, a suspension is sprayed into the plasma that contains both large and small particles in non-homogeneous distribution. The suspension has to be thinned out sharply so that one titanium dioxide particle after another can be detected and analyzed. Ions are formed out of these particles in hot plasma of about 7,000 Kelvins. They get to the spectrometer’s detector as an ion cloud, and are counted within the briefest measurement time of about three milliseconds. Signal intensity correlates to particle size. “We convert the intensity into nanometers. At the same time, we count particle signals, from which we calculate particle concentration with up to ten percent accuracy. We can establish exactly how many particles are of a specific size,” says Sommers, explaining the procedure.

It was IGB scientists who originally developed the methods for measuring titanium oxide nanoparticles in wastewater. “But the process is generally suitable for complex media, and can also be applied to sunscreen lotions,” the researcher indicates. A unique feature of this approach: the IGB team performs the data analysis and data processing without specialized software. “We have statistically evaluated the raw data using a standard computer program, and thus can work irrespective of the producer. Compared to existing methods, SP-ICP-MS involves a rapid process that uses detection limits that extend down to the ultra-trace amount scale below ppm.” For example, one sample of just a few milliliters can be examined in about six minutes.

Cosmetics makers, nanotechnology businesses, and consumers can benefit from the particle analysis for quality assurance of sun protection and body care products, but also use them for analyzing water, drinking water, and food. The researchers are planning to measure other nanoparticles in the future as well, such as silica dioxide. One can only determine whether a product contains silica dioxide through complex measurements. In order to establish the presence of nanoparticles, one must first determine their size or size distribution. Based on the EU’s definition, declaration requirements apply to a nanomaterial if at least 50 percent of the contained particles are of a size measuring between 1 and 100 nanometers (nm). Previous analysis methods are hitting their limits here. These make it possible to establish particle sizes only in pure solutions. They are not suited for analysis of complex media that one finds in modern cosmetics. In addition, nanoparticles with various chemical properties cannot be differentiated from each other this way.




Fonte: Fraunhofer


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About Fraunhofer-Gesellschaft
The Fraunhofer-Gesellschaft is the leading organization for institutes of applied research in Europe, undertaking contract research on behalf of industry, the service sector and the government. Commissioned by customers in industry, it provides rapid, economical and immediately applicable solutions to technical and organizational problems. Within the framework of the European Union's technology programs, the Fraunhofer-Gesellschaft is actively involved in industrial consortiums which seek technical solutions to improve the competitiveness of European industry.

The Fraunhofer-Gesellschaft

Research of practical utility lies at the heart of all activities pursued by the Fraunhofer-Gesellschaft. Founded in 1949, the research organization undertakes applied research that drives economic development and serves the wider benefit of society. Its services are solicited by customers and contractual partners in industry, the service sector and public administration. The organization also accepts commissions from German federal and Laender ministries and government departments to participate in future-oriented research projects with the aim of finding innovative solutions to issues concerning the industrial economy and society in general.

Applied research has a knock-on effect that extends beyond the direct benefits perceived by the customer: Through their research and development work, the Fraunhofer Institutes help to reinforce the competitive strength of the economy in their local region, and throughout Germany and Europe. They do so by promoting innovation, accelerating technological progress, improving the acceptance of new technologies, and not least by disseminating their knowledge and helping to train the urgently needed future generation of scientists and engineers.

As an employer, the Fraunhofer-Gesellschaft offers its staff the opportunity to develop the professional and personal skills that will allow them to take up positions of responsibility within their institute, in other scientific domains, in industry and in society. Students working at the Fraunhofer Institutes have excellent prospects of starting and developing a career in industry by virtue of the practical training and experience they have acquired.

At present, the Fraunhofer-Gesellschaft maintains more than 80 research units, including 56 Fraunhofer Institutes, at 40 different locations in Germany. The majority of the 12,500 staff are qualified scientists and engineers, who work with an annual research budget of €1.2 billion. Of this sum, more than €1 billion is generated through contract research. Two thirds of the Fraunhofer-Gesellschaft’s contract research revenue is derived from contracts with industry and from publicly financed research projects. Only one third is contributed by the German federal and Laender governments in the form of institutional funding, enabling the institutes to work ahead on solutions to problems that will not become acutely relevant to industry and society until five or ten years from now.

Affiliated research centers and representative offices in Europe, the USA and Asia provide contact with the regions of greatest importance to present and future scientific progress and economic development.

The Fraunhofer-Gesellschaft is a recognized non-profit organization which takes its name from Joseph von Fraunhofer (1787-1826), the illustrious Munich researcher, inventor and entrepreneur.

Nanoparticles Used to Breach Mucus Barrier in Lungs



Proof-of-concept study conducted in mice a key step toward better treatments for lung diseases


FAST FACTS:

  • Nanotechnology could one day provide an inhaled vehicle to deliver targeted therapeutic genes for those suffering from life-threatening lung disorders.
  • Researchers may have discovered first gene delivery system that efficiently penetrates the hard-to-breach human airway mucus barrier of lung tissue.
nanoparticles











Researchers at the Johns Hopkins University School of Medicine, Johns Hopkins University Department of Chemical and Biomolecular Engineering, and Federal University of Rio de Janeiro in Brazil have designed a DNA-loaded nanoparticle that can pass through the mucus barrier covering conducting airways of lung tissue — proving the concept, they say, that therapeutic genes may one day be delivered directly to the lungs to the levels sufficient to treat cystic fibrosis (CF), chronic obstructive pulmonary disease, asthma and other life-threatening lung diseases.   
nanoparticles
DNA-loaded nanoparticles may someday be
able to penetrate the human airway mucus
barrier of lung tissue.
Credit: N.R.Fuller, Sayo-Art LLC
“To our knowledge, this is the first biodegradable gene delivery system that efficiently penetrates the human airway mucus barrier of lung tissue,” says study author Jung Soo Suk, Ph.D., a biomedical engineer and faculty member at the Center for Nanomedicine at the Wilmer Eye Institute at Johns Hopkins. A report on the work appeared in theProceedings of the National Academy of Sciences on June 29.
The mucus barrier protects foreign materials and bacteria from entering and/or infecting lungs. In healthy lungs, inhaled matter is typically trapped in airway mucus and subsequently swept away from the lungs via beating activities of cilia, or small, hairlike strands, to the stomach to be eventually degraded. Unfortunately, Suk notes, this essential protective mechanism also prevents many inhaled therapeutics, including gene-based medicine, from reaching their target.  
His team’s experiments with human airway mucus and small animals, Suk adds, were designed as a proof-of-concept study demonstrating that placing corrective or replacement genes or drugs inside a man-made biodegradable nanoparticle “wrapper” that patients inhale could penetrate the mucus barrier and one day be used to treat serious lung disorders. What’s more, because a single dose might theoretically last for several months, patients would experience fewer side effects common to drugs that must be taken regularly over long stretches of time.   
Suk says their work with nanoparticles grew out of failed efforts to deliver treatments to people with lung diseases. In patients with CF, for instance, they experience a buildup of excess mucus caused by impaired ciliary beating, resulting in an ideal breeding ground for chronic bacterial infection and inflammation. This pathogenic process not only worsens patients’ quality of life — and often puts patients in life-threatening situations — but it also makes the airway mucus harder to overcome by inhaled therapeutic nanoparticles. 
Most of the existing drugs for CF help clear infections but do not solve the disease’s underlying problems. A couple of recently approved drugs designed to target the underlying cause of CF require daily treatment for the entire lifetime and can benefit only a subpopulation of patients with specific types of mutations. Yet this study, Suk notes, has demonstrated that delivering normal copies of CF-related genes or corrective genes via the mucus-penetrating DNA-loaded nanoparticles could mediate production of normal, “functional” proteins long term. This could eventually become an effective therapy for the lungs of patients, regardless of the mutation type.
To date, no one has been able to figure out how to efficiently deliver those genes to the lungs, Suk says, noting that experiments using deactivated viruses to carry them have proven inefficient and expensive, and could potentially lead to severe side effects. Moreover, the body could develop resistance to these virus-based delivery systems, rendering the delivery mechanism moot.
Alternatively, numerous nonviral, synthetic systems have been widely tested. However, previous research had shown that most of the nonviral, DNA-loaded nanoparticles possess positive charge that caused them to adhere to negatively charged biological environments, in this case the mucus covering the lung airways. In other words, conventional nanoparticles are too sticky to avoid unwanted off-target interactions during their journey toward the target cells. Further, these particles tend to rapidly aggregate in physiological conditions, rendering them too large to penetrate the mesh of airway mucus.
For its design, the team developed a simple method to densely coat the nanoparticles with a nonsticky polymer called PEG, neutralized the charge and created a nonsticky exterior. They showed that these nanoparticles retained their sizes at a physiological environment and are capable of rapidly penetrating human airway mucus freshly collected from patients visiting the Johns Hopkins Adult Cystic Fibrosis Program directed by Michael Boyle, a co-author of the paper. The team also made the whole delivery system biodegradable so that it would not build up inside the body.
To test whether the system provides efficient gene transfer to the lungs of animals, the researchers packed them with a gene that makes light-generating proteins once delivered into the target cells. They demonstrated that inhaled delivery of the genes via the mucus-penetrating nanoparticles resulted in widespread production of the protein to levels superior to gold-standard, nonviral platforms, including a clinically tested system. In addition, they showed that the treated lungs lit up for up to four months after a single dosing.  
“With one dose, you can get gene expression — i.e., production of therapeutic proteins — for several months,” Suk says, adding that the nanoparticles did not appear to show any adverse effects, such as increased lung inflammation.
Suk and his team caution that more animal studies are needed to confirm and refine their proof-of-concept study, and that treatment of human disorders with nanowrapped therapies is years away.
Additional Johns Hopkins researchers include Panagiotis Mastorakos, Jane Chisholm, Eric Song, Won Kyu Choi and Justin Hanes.
The study was funded by the National Heart, Lung, and Blood Institute of the National Institutes of Health under grant numbers P01 HL51811 and R01HL127413 and the Cystic Fibrosis Foundation under grant numbers HANES07XX0 and HANES15G0.