Friday, November 6, 2009

This week in nanotechnology, Nov.6, 2009

New research reported this week has established an industrially relevant process for assembling carbon nanotubes that allows them to efficiently be made into fibers, coatings and films – the basic forms of material that can be used in engineering applications. By this advance, materials engineers can now access established technology that had been developed for processing polymers through solution phase methods – the industrial-scale processes that are at the heart of the plastics industry.

Duke University bioengineers have developed a simple and inexpensive method for loading cancer drug payloads into nanoscale delivery vehicles and demonstrated in animal models that this new nanoformulation can eliminate tumors after a single treatment. After delivering the drug to the tumor, the delivery vehicle breaks down into harmless byproducts, markedly decreasing the toxicity for the recipient.

Another nanomedicine report this week showed that a gold nanocage covered with a polymer can be employed as a smart drug delivery system. The smart nanocage is designed to be filled with a medicinal substance, such as a chemotherapy drug or bactericide. Releasing carefully titrated amounts of a drug only near the tissue that is the drug's intended target, this delivery system will maximize the drug's beneficial effects while minimizing its side effects.

Picture the ultimate in miniaturization—functional machines built out of individual molecules, mere atoms in size. In a breakthrough development, researchers from the Institute of Materials Research and Engineering in Singapore have reported the invention of an essential component for single-molecule mechanical machines: a molecular gear that can be controllably rotated with a 100% rate of success.

Representation of a molecular gear pinned to a gold surface, with an STM tip close to one of the gear's teeth

Representation of a molecular gear pinned to a gold surface, with an STM tip close to one of the gear’s ‘teeth’.

Converting sunlight to electricity might no longer mean large panels of photovoltaic cells atop flat surfaces like roofs. Using zinc oxide nanostructures grown on optical fibers and coated with dye-sensitized solar cell materials, researchers at the Georgia Institute of Technology have developed a new type of three-dimensional photovoltaic system. The approach could allow PV systems to be hidden from view and located away from traditional locations such as rooftops.

University of Utah chemists demonstrated the first conclusive link between the size of catalyst particles on a solid surface, their electronic properties and their ability to speed chemical reactions. The study is a step toward the goal of designing cheaper, more efficient catalysts to increase energy production, reduce Earth-warming gases and manufacture a wide variety of goods from medicines to gasoline.

Imitating photosynthesis in plants? If we were to accomplish this, mankind would have a little less to worry about. Chemists from the University of W├╝rzburg have now made progress on the road to achieving artificial photosynthesis. The structure that has been developed in the university's Organic Chemistry laboratory is fascinatingly complex: thousands of similar molecules are packed together to create a capsule that is filled with molecules of a different kind. The diameter of one capsule is a mere 20 to 50 nanometers.