The toxicity issues surrounding carbon nanotubes (CNTs) are highly relevant for two reasons: Firstly, as more and more products containing CNTs come to market, there is a chance that free CNTs get released during their life cycles, most likely during production or disposal, and find their way through the environment into the body. Secondly, and much more pertinent with regard to potential health risks, is the use of CNTs in biological and medical settings. Some groups are using CNTs in research for vaccination as well as gene and cancer therapy. Here, the CNT applications are designed to interact directly with the immune system. Understanding the interplay between CNTs and immune proteins is therefore critical for both improving CNT applications in biology and medicine and avoiding potentially noxious immune responses.
Self-cleaning, water and dirt-repellent coatings have differing properties, functional principles and manufacturing processes. Self-cleaning of the 'Lotus Effect' type has its basis in chemical-physical principles - these surfaces are characterised by a special roughness and are strongly water-repellent; in the ideal case, rain is sufficient for cleaning. 'Easy-to-Clean' materials, in contrast, have a particularly flat surface, which is both water and dirt-repellent on the basis of chemical aspects. Although the amount of mechanical cleaning may be reduced, they are not self-cleaning. A third form of self-cleaning is that based on photo catalysis by nano titanium dioxide. On such surfaces UV radiation produces oxygen radicals that decompose organic material, which in turn is removed in the rain by a water film.
The OECD has just published a 111-page book on nanotechnology business that attempts to provide comprehensive, internationally comparable information on how different types of companies are affected by nanotechnology, how they use it in their innovative activities, how they acquire or develop relevant competences, as well as on the specific commercialization challenges they face. It also addresses the different role that new and small as well as larger companies will play in the commercialization of nanotechnology.The case studies provide qualitative insights into the commercialization of nanotechnology from the viewpoint of companies and thus complement studies which have relied primarily on publication and patent data or statistical surveys.
A key hurdle in realizing high-efficiency, cost-effective solar energy technology is the low efficiency of current power cells. In order to achieve maximum efficiency when converting solar power into electricity, ideally you need a solar panel that can absorb nearly every single photon of light - across the entire spectrum of sunlight and regardless of the sun's position in the sky. One way to achieve suppression of sunlight's reflection over a broad spectral range is by using nanotextured surfaces that form a graded transition of the refractive index from air to the substrate. Researchers in Finland have now demonstrated a scalable, high-throughput fabrication method for such non-reflecting nanostructured surfaces.
Nanotechnology researchers working on self-powered nanodevices - nanoscale systems that scavenge energy from their surrounding environment - have been experimenting with various power sources ranging from piezoelectric systems to sound. However, the most abundant energy available in biosystems is chemical and biochemical energy, such as glucose. Researchers in China have now reported a nanowire-based biofuel cell based on a single proton conductive polymer nanowire for converting chemical energy from biofluids into electricity, using glucose oxidase and laccase as catalyst. The output of this biofuel cell is sufficient to drive pH, glucose or photon sensors. The high output power, low cost and easy fabrication process, large-scale manufacturability, high 'on-chip' integrability and stability demonstrates its great potential for in vivo biosensing.
Although the literature grows on the use of science to inform decisions on the environmental, health and safety implications of nanotechnology, little has been published by those who make such decisions. In a recent commentary in Nature Nanotechnology, officials of the US Environmental Protection Agency (EPA), the European Commission and the Organisation for Economic Co-operation and Development (OECD), discuss the types of decision facing government regulators, the new considerations nanotechnology brings to decision-making, the role of science in informing decisions, how regulators cooperate internationally on policy issues, and the challenges that lie ahead. The authors provide an overview of key reports and regulations and then discuss the complexity of issues with regard to addressing nanomaterials within the context of existing regulations and the need to weigh nanomaterial risk and benefits.
'Nano Textiles' can be produced by a variety of methods. The key difference among them is whether synthetic nanoparticles are integrated into the fibres or the textile, or are applied as a coating on the surface, and/or whether nanoparticles are added to the nanoscale fibres or coating. This article clarifies nano-textile manufacturing processes and application areas, and gives an overview about the potential effects on the environment and health. Many questions remain unanswered, however, there is a need for considerably more research not only for product development but also into the usefulness and risks which nano-textiles give rise to. The open questions have prompted the Swiss Textile Federation to undertake a joint project with the Swiss Federal Laboratories for Materials Science and Technology (EMPA) entitled 'Nanosafe Textiles' and to initiate discussions on the topic.
With the advance of nanomedicine, bio-nanotechnology, and molecular biology, researchers require tools that allow them to work on a single cell level. These tools are required to probe individual cells, monitor their processes, and control/alter their functions through nanosurgery procedures and injection of drugs, DNA etc. - all without damaging the cells, of course. Researchers have now developed a multifunctional endoscope-like device, using individual CNTs for prolonged intracellular probing at the single-organelle level, without any recordable disturbance to the metabolism of the cell. These endoscopes can transport attoliter volumes of fluid, record picoampere signals from cells, and can be manipulated magnetically. Furthermore, the tip deflects with submicrometer resolution, and the attachment of gold nanoparticles allows intracellular fingerprinting using surface-enhanced Raman spectroscopy (SERS).