Directional Nanoplasmonic Antennas for Self-Referenced Refractometric Molecular Analysis
Artikel i vetenskaplig tidskrift, 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

Författare

Martin Wersäll

Chalmers, Teknisk fysik, Bionanofotonik

Ruggero Verre

Chalmers, Teknisk fysik, Bionanofotonik

Mikael Svedendahl

Chalmers, Teknisk fysik, Bionanofotonik

Peter Johansson

Chalmers, Teknisk fysik, Bionanofotonik

Mikael Käll

Chalmers, Teknisk fysik, Bionanofotonik

Timur Shegai

Chalmers, Teknisk fysik, Bionanofotonik

Journal of Physical Chemistry C

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

Vol. 118 21075-21080

Ämneskategorier

Den kondenserade materiens fysik

DOI

10.1021/jp5064929