Using gold nanoparticles to destroy viruses

HIV, dengue, papillomavirus, herpes and Ebola – these are just some of the many viruses that kill millions of people every year, mostly children in developing countries. While drugs can be used against some viruses, there is currently no broad-spectrum treatment that is effective against several at the same time, in the same way that broad-spectrum antibiotics fight a range of bacteria. But researchers at EPFL's Supramolecular Nano-Materials and Interfaces Laboratory – Constellium Chair (SUNMIL) have created gold nanoparticles for just this purpose, and their findings could lead to a broad-spectrum treatment. Once injected in the body, these nanoparticles imitate human cells and “trick” the viruses. When the viruses bind to them – in order to infect them – the nanoparticles use pressure produced locally by this link-up to “break” the viruses, rendering them innocuous. The results of this research have just been published in Nature Materials.

Guanidinium stabilizes perovskite solar cells at 19% efficiency

With the power-conversion efficiency of silicon solar cells plateauing around 25%, perovskites are now ideally placed to become the market’s next generation of photovoltaics. In particular, organic-inorganic lead halide perovskites offer manufacturing versatility that can potentially translate into much higher efficiency: studies have already shown photovoltaic performances above 20% across different solar cell architectures built with simple and low-cost processes.

Antarctica: the wind sublimates snowflakes

Researchers have observed and characterized a weather process that was not previously known to occur in Antarctica's coastal regions. It turns out that the katabatic winds that blow from the interior to the margins of the continent reduce the amount of precipitation (mainly snowfall) -- which is a key factor in the formation of the ice cap. By forming a very dry layer of air in the first kilometer or so of atmosphere, the winds turn the falling snowflakes during their fall directly from their solid state into water vapor in a process known as sublimation.