Volume 4 Issue 7, July 2009

The relationship between humans and technology is often viewed as a debate between technophobes who oppose technology, irrespective of its benefits, and technophiles who think that all technology is good. Chris Toumey prefers the cyborg point of view.

A collaboration between China's leading university and one of the world's biggest industrial companies is bringing a range of nanotube-based materials and devices to the market.

Computational screening has turned up a fullerene derivative that might help fight the HIV virus.

Using simple components such as oil, salt water, lipids and proteins, plus routine genetic engineering techniques, it is possible to create simple nanofluidic circuits.

A new approach to mass spectrometry based on nanoelectromechanical systems removes the need to ionize molecules before their mass can be determined.

Experiments on single-crystal nanobeams have revealed several new aspects of a phenomenon that has puzzled physicists for decades — the metal–insulator transition in vanadium dioxide.

Inspired by the feet of the gecko lizard, researchers have tweaked a conventional plasma etching chamber so that it can make reusable adhesives that could have applications in the semiconductor industry.

Mice inhaling low levels of multiwalled carbon nanotubes show suppressed immune function. New studies suggest that this suppression originates from signals in the lungs.

Shape-memory alloys undergo reversible transformations between two distinct phases. Now researchers have shown that nanoscale pillars made of shape-memory alloys have a figure of merit for mechanical damping — substantially higher than the figures previously reported for bulk materials — making these nanopillars attractive for use in future microscale and smaller devices.

Many strongly correlated electron systems have a domain structure that obscures the fundamental properties of the homogeneous material. Experiments on single-domain nanobeams made of vanadium dioxide have revealed several new aspects of the metal–insulator transition in this material.

Excitons are created when a carbon nanotube absorbs photons. However, the triplet exciton is usually optically inactive, preventing its direct observation, lowering photocurrent efficiency and making optical injection of spin-polarized carriers impossible. Optical excitation of the triplet exciton has now been achieved.

Multifunctional nanostructures have been created from DNA-based anisotropic, branched and crosslinkable building blocks — ABC monomers. Using these monomers, a target-driven polymerization process is demonstrated where polymers are generated only in the presence of a specific DNA molecule, leading to highly sensitive pathogen detection. The nanoarchitectures can also be used to deliver drugs to cells.

Aqueous droplets connected by single lipid bilayers have been used to examine the properties of protein channels and pores, and networks of droplets can form microscale batteries and detect light. Now, by inserting an engineered pore with diode-like properties into the interface bilayers, droplet networks that mimic simple electronic devices have been produced.

Gold nanorods added to a laboratory-constructed estuarine mesocosm can accumulate in sediments, biofilms and various organisms such as fish, snails and shrimp. Most of the nanorods ended up in biofilms and clams, indicating that these nanoparticles could readily pass from the water column into the marine food web.

Mass detection of single biological molecules in real time by a nanoelectromechanical system (NEMS) is demonstrated for the first time, and this is used to perform first generation NEMS-based mass spectrometry. Precipitous frequency shifts, proportional to the mass of the molecules, are recorded in real time by the NEMS mass spectrometry system as protein molecules and nanoparticles adsorb, one-by-one, onto an ultrahigh frequency NEMS resonator.

It has been shown that inhaling multiwalled carbon nanotubes does not lead to significant lung inflammation, but can suppress the immune function of mice. Now it is demonstrated that signals in the lung can activate signals in the spleen to inhibit the immune function of mice inhaling low levels of nanotubes.

A class of core–shell nanoparticles self-assembled from amphiphilic peptides can kill a range of bacteria, yeast and fungus. They are more potent than their unassembled peptide counterparts and can suppress bacterial growth in the brains of rabbits infected with meningitis. These particles, which carry a high number of positive charges, are promising antimicrobial agents.