Scientists from the University of Bath (UK) and Northwestern University (USA) have developed a new type of sensor platform using a gold nanoparticle array, which is 100 times more sensitive than current similar sensors.
The sensor is made up of a series of gold disk-shaped nanoparticles on a glass slide. The team at Bath discovered 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, from the University of Bath's Department of Physics, hope that in the future they can use the technology to develop new ultra-sensitive sensors for air pollution or for medical diagnostics.
Dr Ventsislav Valev, Royal Society Research Fellow and Reader in Physics at the University of Bath, led the work with Research Associate David Hooper.
He explained: "This new mechanism has great potential for detecting small molecules. It is 100 times more sensitive than current methods.
"The gold nanoparticle disks are arranged on a glass slide in a very precise array - 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.
"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."
The study has demonstrated the proof of principle for this new sensing mechanism. The team would next like to test the sensing of various types of chemicals and expects the technique to be available to other scientists to use within five years.
The nanoparticles were fabricated by researchers at Northwestern University, Illinois (USA).
David C. Hooper, Christian Kuppe, Danqing Wang, Weijia Wang, Jun Guan, Teri W. Odom, and Ventsislav K. Valev (2019) "Second Harmonic Spectroscopy of Surface Lattice Resonances" is published in Nano Letters DOI: 10.1021/acs.nanolett.8b03574
Vicky Just | EurekAlert!
FAST detects neutral hydrogen emission from extragalactic galaxies for the first time
02.07.2020 | Chinese Academy of Sciences Headquarters
First exposed planetary core discovered
01.07.2020 | Universität Bern
Solar cells based on perovskite compounds could soon make electricity generation from sunlight even more efficient and cheaper. The laboratory efficiency of these perovskite solar cells already exceeds that of the well-known silicon solar cells. An international team led by Stefan Weber from the Max Planck Institute for Polymer Research (MPI-P) in Mainz has found microscopic structures in perovskite crystals that can guide the charge transport in the solar cell. Clever alignment of these "electron highways" could make perovskite solar cells even more powerful.
Solar cells convert sunlight into electricity. During this process, the electrons of the material inside the cell absorb the energy of the light....
Empa researchers have succeeded in applying aerogels to microelectronics: Aerogels based on cellulose nanofibers can effectively shield electromagnetic radiation over a wide frequency range – and they are unrivalled in terms of weight.
Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic...
A promising operating mode for the plasma of a future power plant has been developed at the ASDEX Upgrade fusion device at Max Planck Institute for Plasma...
Live event – July 1, 2020 - 11:00 to 11:45 (CET)
"Automation in Aerospace Industry @ Fraunhofer IFAM"
The Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM l Stade is presenting its forward-looking R&D portfolio for the first time at...
With an X-ray experiment at the European Synchrotron ESRF in Grenoble (France), Empa researchers were able to demonstrate how well their real-time acoustic monitoring of laser weld seams works. With almost 90 percent reliability, they detected the formation of unwanted pores that impair the quality of weld seams. Thanks to a special evaluation method based on artificial intelligence (AI), the detection process is completed in just 70 milliseconds.
Laser welding is a process suitable for joining metals and thermoplastics. It has become particularly well established in highly automated production, for...
02.07.2020 | Event News
19.05.2020 | Event News
07.04.2020 | Event News
03.07.2020 | Life Sciences
03.07.2020 | Studies and Analyses
03.07.2020 | Power and Electrical Engineering