New nanostructure could aid development of better biosensors

A team from Northwestern University in the US have made a new nanotechnology breakthrough that could greatly facilitate the creation of sensitive biosensors in future.

The new nanostructure is capable of absorbing ultra-narrow bands of light spectrum and can be used in a number of applications, also including photothermal therapy, thermo-photovoltaics, heat-assisted magnetic recording, thermal emission and solar-steam generation.

Typically, optical biosensors work by absorbing specific bandwidths of light and shifting spectrum when minor changes in the environment are sensed. The narrower the band of absorbed light, the more sensitive the biosensor.

With this new technology, a bandwidth of just 12 nanometres has been achieved, compared to current plasmonic absorbers used in biosensors that have a resonant bandwidth of 50 nanometres.

Koray Aydin, assistant professor of electrical engineering and computer science in the McCormick School of Engineering, said: "We believe that our unique narrowband absorber design will enhance the sensitivity of biosensors. It's been a challenge to sense very small particles or very low concentrations of a substance."

Dr Aydin is a recognised authority in the fields of metamaterials, plasmonics, nanophotonic devices, solid-state electronics, photovoltaics and nanofabrication.