A metal–organic molecular net has been constructed by scientists in the US to surround a virus particle, giving it stability in air and allowing detailed structural analysis.1
Viruses are tiny infectious agents that self-replicate in the cells of humans, animals, plants and even microorganisms. Scientists study viruses both as threats to health and for their potential use in therapy. However, viruses break down easily when removed from a liquid environment, which hinders their analysis by atomic force microscopy, electron microscopy and mass spectrometry.
This may all be about to change, however, as Bogdan Dragnea and colleagues at Indiana University in the US have constructed a tannic acid and iron(III) molecular net around a single brome mosaic virus particle, stabilising it in non-liquid conditions. The biocompatible net coats the virus with a molecular layer thin enough to follow the underlying morphology, yet still providing a barrier to water. The research team could place the coated virus in air or under vacuum long enough to take measurements and further probe its structure.
Hirotaka Ejima, from the University of Tokyo, Japan, whose 2013 publication2 on the assembly of iron–tannic acid coordination complexes inspired Dragnea’s study, praises the idea to capture a virus in this way. Vinothan Manoharan, a biophysics researcher at Harvard University, US, thinks that Dragnea’s method could help scientists engineer viruses for use as therapeutic agents. ‘For this application, it’s necessary to make the virus stable in environments that are different from that of its host. This [study] demonstrates a simple but remarkably effective way to do this,’ he says.
‘Being able to quantify all the components of a virus will be a great step forward in the direction of a more complete chemical understanding of viruses’, comments Dragnea. He hopes the molecular suit may eventually lead to longer lasting vaccines, which can be preserved without refrigeration or complex storage conditions.