Friday, July 23, 2010

This week in nanotechnology - July 23, 2010

Nanotechnologists at University of Twente's MESA+ research institute have developed a sensor that can detect anthrax spores. The invention is more sensitive and efficient than existing detection methods. The sensor that can detect a biomarker of the spores and thus determine their presence in a concentration one thousand times lower than the known toxic level.

Gene-silencing nanoparticles may put end to mosquito pest. Research conducted by a Kansas State University team may help solve a problem that scientists and pest controllers have been itching to for years. The team investigated using nanoparticles to deliver double-stranded ribonucleic acid, dsRNA – a molecule capable of specifically triggering gene silencing – into mosquito larvae through their food. By silencing particular genes, the dsRNA may kill the developing mosquitoes or make them more susceptible to pesticides.

A new vaccine-delivery patch based on hundreds of microscopic needles that dissolve into the skin could allow persons without medical training to painlessly administer vaccines -- while providing improved immunization against diseases such as influenza. Patches containing micron-scale needles that carry vaccine with them as they dissolve into the skin could simplify immunization programs by eliminating the use of hypodermic needles – and their "sharps" disposal and re-use concerns. Applied easily to the skin, the microneedle patches could allow self-administration of vaccine during pandemics and simplify large-scale immunization programs in developing nations.

vaccine-delivery patch

By imaging the cell walls of a zinnia leaf down to the nanometer scale, energy researchers have a better idea about how to turn plants into biofuels. Using different microscopy methods, the team was able to visualize single cells in detail, cellular substructures, fine-scale organization of the cell wall, and even chemical composition of single zinnia cells, indicating that they contain an abundance of lignocellulose.

To trap and hold tiny microparticles, engineers at Harvard have "put a ring on it," using a silicon-based circular resonator to confine particles stably for up to several minutes. The advance could one day lead to the ability to direct, deliver, and store nanoparticles and biomolecules on all-optical chips.

Scientists at the University of Liverpool have constructed molecular 'knots' with dimensions of around two nanometer. Most molecules are held together by chemical bonds between atoms – 'nano-knots' are instead mechanically bonded by interpenetrating loops. This is an unusual example of 'self-assembly', a process which underpins biology and allows complex structures to assemble from more simple building blocks.

The molecular knots have dimensions of around two nanometers

ETH Zurich researchers have built a transistor whose crucial element is a carbon nanotube, suspended between two contacts, with outstanding electronic properties. A novel fabrication approach allowed the scientists to construct a transistor with no gate hysteresis. This opens up new ways to manufacture nano-sensors and components that consume particularly little energy.

Engineers at Oregon State University have made a significant advance toward producing electricity from sewage, by the use of new coatings on the anodes of microbial electrochemical cells that increased the electricity production about 20 times. The findings bring the researchers one step closer to technology that could clean biowaste at the same time it produces useful levels of electricity – a promising new innovation in wastewater treatment and renewable energy.

Astronomers using NASA's Spitzer Space Telescope have discovered carbon molecules, known as "buckyballs," in space for the first time. The fukkerenes were found in a planetary nebula named Tc 1. Planetary nebulas are the remains of stars, like the sun, that shed their outer layers of gas and dust as they age. A compact, hot star, or white dwarf, at the center of the nebula illuminates and heats these clouds of material that has been shed. The buckyballs were found in these clouds, perhaps reflecting a short stage in the star's life, when it sloughs off a puff of material rich in carbon.