Volume 4 Issue 2, February 2009

From solar power to supercapacitors, nanoscience and technology have the potential to help solve a number of pressing energy problems but, as Richard Jones reports, the credit crunch and wild swings in the price of oil could get in the way of these solutions.

Research into public perceptions of nanotechnology is becoming more rigorous as increasingly complex theoretical models are developed and tested by social scientists.

Theorists have shown that the forces between atoms in an atomic-scale contact can do work when an electronic current is passed through it, opening up the possibility that current could be used to drive atomic-scale motors.

New insights are emerging about the interactions between brain cells and carbon nanotubes, which could eventually lead to the development of nanoengineered neural devices.

Charged nanoparticles can alter the local physical properties of lipid membranes, which could shed new light on the interactions between living cells and nanomaterials.

By measuring changes in the photoluminescence of single-walled carbon nanotubes caused by the presence of molecules that damage DNA, it could be possible to build a biosensor that can identify multiple analytes in real time.

A sample of 1,862 adults was presented with balanced information on the risks and benefits of nanotechnology. Subjects did not react in a uniform manner, but polarized along lines consistent with cultural predispositions towards technological risk generally.

Research suggests that citizens use 'religious filters' as an important cognitive shortcut for many scientific issues, including nanotechnology. Combining the results of surveys in the United States and Europe, it has been found that US respondents were significantly less likely to agree that nanotechnology is morally acceptable than respondents in many European countries. These moral views correlated directly with aggregate levels of religiosity in each country.

Public surveys provide valuable information on how people view nanotechnology, but cannot easily uncover more detailed responses to the complexities of any new technology. Four concurrent workshops debating energy and health nanotechnologies in the US and UK found that energy applications were viewed more positively than those for health in both countries.

Current-induced forces in atomic wires are shown to be non-conservative, which means that they are able to do net work and to drive atomic-scale motors. Numerical simulations are presented of a motor that turns like a waterwheel when current runs through it

Electronic devices based on semiconductor nanowires will rely on the location and number of dopant atoms in the host semiconductor being controlled during the fabrication process. It has now been shown that the properties of dopant atoms — in particular, their ionization energies — change with nanowire radius more markedly than previously predicted.

The electrical conductance of a nanotube decreases when it is heated. This phenomenon is exploited in a new technique called photothermal current microscopy to image the conductance of individual nanotubes and groups of nanotubes.

The photoluminescence properties of carbon nanotubes are sensitive to molecular adsorption. By studying the response of a pair of single-wall carbon nanotubes, researchers have now shown that analytes of biological interest can be identified and measured in real-time within living cells.

Colloidal semiconductor nanocrystals are widely used in biological imaging, but existing synthesis techniques are difficult and require specialized expertise. Here it is shown that the use of DNA as a ligand allows a simpler synthetic protocol to be used, producing biofunctionalized nanocrystals that exhibit strong optical emission in the visible spectrum, minimal toxicity and small hydrodynamic diameter.

Carbon nanotubes can enhance the excitability of neurons by forming tight contacts with the cell membranes to favour electrical shortcuts between the distal and proximal compartments of the neuron.