Researchers from the University of Bristol, Vanderbilt University, and the University of Maryland have found a way to make shaped metal structures on a nanoscale by coating other tiny items. In this case they have coated 4- by 60-nanometer tobacco virus with gold, silver and platinum salts.
They found that in an acidic solution, negatively-charged metal salts react with viral amino acids causing nanoparticles to align on the outer surface of the virus. When the pH of the solution is neutral, positively-charged salts pass through the protein coats of the virus and metal nanoparticles to align inside the viruses.
The process could be used in future to create metal nanowires.