Directional Nanoplasmonic Antennas for Self-Referenced Refractometric Molecular Analysis
Journal article, 2014

Localized surface-plasmon resonance (LSPR) sensors are typically based on tracing resonance peak shifts that precisely follow changes in the local refractive index. Such measurements usually require a spectrometer, a stable light source, and an accurate LSPR position tracing technique. As a simple but efficient alternative, we investigated a self-referenced single-wavelength sensing scheme based on angle-dependent and highly directional radiation patterns originating from a monolayer of asymmetric gold nanodimers. We found that one could easily trace a model biotinneutravidin recognition reaction as well as minute bulk refractive index changes, by measuring the intensity ratio between the light scattered in two different directions with respect to the dimers. The refractometric resolution of the methodology was estimated to be on the order of Delta n approximate to 10(-5) RIU. These results may be particularly useful for label-free biosensing applications that require a combination of simple and cost-effective optical readout with a reasonable sensitivity.

sensitivity

proteins

surface-plasmon resonance

biosensors

light-emission

dipoles

sensors

lithography

interface

Author

Martin Wersäll

Chalmers, Applied Physics, Bionanophotonics

Ruggero Verre

Chalmers, Applied Physics, Bionanophotonics

Mikael Svedendahl

Chalmers, Applied Physics, Bionanophotonics

Peter Johansson

Chalmers, Applied Physics, Bionanophotonics

Mikael Käll

Chalmers, Applied Physics, Bionanophotonics

Timur Shegai

Chalmers, Applied Physics, Bionanophotonics

Journal of Physical Chemistry C

1932-7447 (ISSN) 1932-7455 (eISSN)

Vol. 118 36 21075-21080

Subject Categories

Condensed Matter Physics

DOI

10.1021/jp5064929

More information

Created

10/7/2017