News & Views in 2011

Bioinspired nanoreactor arrays can be used to controllably mix subattolitre volumes of liquids.

A four-level conductance switch can be created by using a scanning tunnelling microscope to remove a hydrogen atom from the central cavity of a porphyrin molecule.

Laser-based imaging can distinguish between semiconducting and metallic nanotubes in vitro and in vivo, offering a way to study the interactions of carbon nanostructures in biological systems without the use of labels.

Artificial nanopores with hydrophobic surface patches can be reversibly filled with water by applying electric fields.

Lipid monolayers and bilayers can stabilize networks of water droplets inside larger drops of oil to create structures that could have a range of applications.

The cycle of cell birth, growth and division can affect the uptake and dilution of nanoparticles in cells, suggesting that the evolution of nanoparticle dose within a cell population is linked to the life cycle of cells.

Signals that damage cells grown underneath a cellular barrier are transmitted only when the barrier is more than one layer thick.

Incorporating gold nanowires into porous alginate scaffolds can improve the conductivity of engineered heart patches made from these materials.

A nanomechanical beam coupled to an optical cavity can be operated as a non-volatile memory element.

Electric currents can be steered by coupling the flow of electrons and ions in films of gold nanoparticles coated with ionic ligands.

A surface acoustic wave can be used to remove a single electron from a quantum dot, drag it along a nanowire, and deposit it in a second quantum dot.

The observation that charges flowing through one quantum wire can drag charges in a second, unconnected wire either forwards or backwards requires a re-interpretation of Coulomb drag.

Electrons from the tip of a scanning tunnelling microscope can be used to drive and monitor the directional rotation of a single molecule on a metal surface.

Risk assessments of products containing nanomaterials require both the materials in the products and the materials emitted during their use to be analysed so that realistic exposures can be determined.

Graphene membranes allow measurements of surface chemistry under realistic conditions.

Plasmons in graphene nanoribbons have widely tunable frequencies and interact strongly with light.

The adhesion energies for atomically thin graphene membranes on silicon dioxide substrates have now been measured.

Fibrous proteins from bacteria can be used to make biofilms with electrical conductivities that are comparable to those measured in conducting polymers.

Inorganic nanoparticles can self-assemble into uniformly sized supraparticles in a process governed by competition between electrostatic and van der Waals forces.

Complex molecular circuits with reliable digital behaviour can be created using DNA strands.