A new sensor has been developed which can detect and measure single particles using a 'whispering-gallery' technique.
Dr Lan Yang, assistant professor of electrical and systems engineering at Washington University, led the team in creating the high-Q microresonator, which is etched out of glass layers on silicon wafers.
An example of whispering gallery can be found in St Paul's Cathedral in the UK, where two people are able to communicate from either end of the room by whispering closely to the wall.
Yang explained that it will benefit many scientists and researchers to be able to measure particles effectively using this sensor.
He said: "Size is a key parameter that significantly affects the physical and chemical properties of nanoparticles. It plays a crucial role in the applications of nanoparticles both in science and in industry.
Last month, a team of researchers at the University of Lleida revealed that the sensor used in an optical computer mouse is suitable for detecting counterfeit euro coins.