Scientists have developed what they say is the world’s most powerful optical microscope that can allow them to watch live viruses in action.
British researchers who helped develop the microsphere claimed that the instrument is capable of examining objects as small as 50 nanometres across — 20 times smaller than the present limit for optical microscopes. “This is a world record in terms of how small an optical microscope can go by direct imaging under a light source covering the whole range of optical spectrum, said Prof. Lin Li from the University of Manchester who led the project.
“Not only have we been able to see items of 50 nanometres, we believe that is just the start and we will be able to see far smaller items,” Prof. Lin was quoted as saying by the Daily Mail.
There are 10 million nanometres in a centimetre. And the researchers said the new microscope would allow scientists to look at tiny details inside cells and even “live” viruses. A cold virus is 20 nanometres in diameter. “Theoretically, there is no limit on how small an object we will be able to see,” said Prof. Lin.
Electron microscopes, which use a focused beam of electrons instead of light, can image extremely small objects but have limitations.
Either they are designed only to view surface details, or they require extremely thin specimen sections, making it difficult to image fine biological structures. But, the new instrument employs “superlenses” in the form of tiny “microspheres” — which are small spherical particles — to push the technical boundaries of optical microscopes.
Prof. Lin said: “The common way of seeing tiny items presently is with an electron microscope, and even then you cannot see inside a cell — only the outside. Optical fluoresce microscopes can see inside the cells indirectly by dying them, but these dyes cannot penetrate viruses.