Powerful microscope to solve virus riddle

The standard optical microscope can only see items around 1 micrometre – 0.001mm – clearly, but researchers from the University of Manchester have developed a powerful microscope that can see 20 times smaller

By combining an optical microscope with a transparent microsphere – dubbed the microsphere nanoscope – researchers can see items at 50 nanometres under normal lights. The microscope could revolutionise the way in which we study viruses and diseases.

Scientists hope the new microscope could be used to examine inside human cells, and examine live viruses for the first time to potentially see what causes them.

Currently only the outside of cells can be visualised with an electron microscope. Optical fluorescent microscopes can see inside the cells, but cells have to be dyed first – something which doesn’t work for viruses, but the new technique could change that.

“Seeing inside a cell directly without dying and seeing living viruses directly could revolutionise the way cells are studies and allow us to examine closely viruses and biomedicine for the first time,” said Professor Lin Li.

The nano-imaging system is based on capturing optical, near-field virtual images – which are free from optical diffraction – and amplifying them using a microsphere, a tiny spherical particle which is further relayed and amplified by the standard optical microscope.

“This is a world record in terms of how small an optical microscope can do by direct imaging under a light source covering the whole range of the optical spectrum,” said Li. “Not only have we been able to see items of 50 nanometres, we believe that this is just the start and we will be able to see far smaller items. Theoretically, there is no limit on how small an object will be will be able to see.”