The Whispering Gallery-Mode Biosensor is a new ultra-sensitive biosensor developed by researchers at New York University's Polytechnic Institute which claims to make the process of diagnosing diseases faster. Led by Professor Stephen Arnold, the researchers have developed this speedy new sensor which is fast enough to identify viruses in a matter of minutes while being sensitive enough to identify viruses the size of MS2 which is the smallest known RNA virus particle. Traditional techniques have required weeks to identify viruses this small though the Whispering Gallery-Mode Biosensor claims to do the same in a few minutes through a very inexpensive method.
The biosensor gets its name from the Whispering Gallery located in St. Paul’s Cathedral, London. The unique gallery features extraordinary acoustics that allow the curvature of its wall to carry sounds smoothly next to it allowing even whispers to be heard anywhere next to the gallery’s circular wall. Using the same physical principles as the Whispering Gallery, the Whispering Gallery-Mode Biosensor uses light instead of sound to detect the presence of viruses. The sensor comes with a glass microsphere at its heart. A fiber optic cable leads a tunable laser into the sphere and the light bounces off the curves of the sphere just like sound bounces off the curved wall in the Whispering Gallery covering every point within the microsphere.
The presence of virus particles changes the resonant properties of the sphere and this affect the laser too. The change in resonance frequencies can be measured and the difference can potentially indicate the presence of certain viruses. To check for specific viruses, gold nanoparticles can be used to coat the microsphere which would then attract specific viruses or proteins and make checking for certain viruses even quicker. The Whispering Gallery-Mode Biosensor has been patented though researchers are still tweaking it further before launching it in the market.