Abstract

We propose two-focus fluorescence correlation spectroscopy (2fFCS) on basis of plasmonic nanoantennas that provide distinct hot spots that are individually addressable through polarization, yet lie within a single diffraction limited microscope focus. The importance of two-focus FCS is that a calibrated distance between foci provides an intrinsic calibration to derive diffusion constants from measured correlation times. Through electromagnetic modelling we analyze a geometry of perpendicular nanorods, and their inverse, i.e., nanoslits. While we find that nanorods are not suited for nano-antenna enhanced 2fFCS due to substantial background signal, a nanoslit geometry is expected to provide a di tinct cross-correlation between orthogonally polarized detection channels. Furthermore, by utilizing a periodic array of nanoslits instead of a single pair, the amplitude of the cross-correlation can be enhanced. To demonstrate this technique, we present a proof of principle experiment on the basis of a periodic array of nanoslits, applied to lipid diffusion in a supported lipid bilayer.

Details

Title
Nano-antenna enhanced two-focus fluorescence correlation spectroscopy
Author
Langguth, Lutz 1 ; Szuba, Agata 2 ; Mann, Sander A 1 ; Garnett, Erik C 1 ; Koenderink, Gijsje H 2 ; Koenderink, A Femius 1   VIAFID ORCID Logo 

 Center for Nanophotonics, AMOLF, Amsterdam, The Netherlands 
 Biological Soft Matter Group, AMOLF, Amsterdam, The Netherlands 
Pages
1-9
Publication year
2017
Publication date
Jul 2017
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
1956167339
Copyright
© 2017. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.