A team of British and U.S. scientists have built a new sensor platform using a gold nanoparticle array.
According to the University of Bath and Northwestern University scientists, the gold nanoparticle array is said to be 100 times more sensitive than current similar sensors.
The Bath-Northwestern invention is made up of a series of gold disk-shaped nanoparticles on a glass slide.
The Bath group were the first to discover that when they shone an infra-red laser at a precise arrangement of the particles, they started to emit unusual amounts of ultra violet (UV) light.
This mechanism for generating UV light is affected by molecules binding to the surface of the nanoparticles, providing a means of sensing a very small amount of material.
The researchers hope that in the future they can use the technology to develop new ultra-sensitive sensors for air pollution or medical diagnostics.
The gold nanoparticle disks have been arranged on a glass slide in a very precise array that changing the thickness and separation of the disks completely changes the detected signal.
“When molecules bind to the surface of a gold nanoparticle, they affect the electrons at the gold surface, causing them to change the amount of UV light they emit,” says Bath’s Dr Ventsislav Valev. “The amount of UV light emitted would depend on the type of molecules that bind to the surface.”
“This technique could enable ultra-sensitive detection of molecules in tiny volumes. It could in the future be used for detecting very low concentrations of biological markers for the early diagnostic screening for diseases, such as cancer.”
V.K Valev and D.C Hooper/University of Bath