Open AccessObserving single protein binding by optical transmission through a double nanohole aperture in a metal film
Author(s) -
Ahmed Al Balushi,
Ana Zehtabi-Oskuie,
Reuven Gordon
Publication year - 2013
Publication title -
biomedical optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.362
H-Index - 86
ISSN - 2156-7085
DOI - 10.1364/boe.4.001504
Subject(s) - streptavidin , optical tweezers , materials science , biotin , particle (ecology) , transmission (telecommunications) , molecule , optics , nanotechnology , chemistry , physics , computer science , telecommunications , organic chemistry , biochemistry , oceanography , geology
We experimentally demonstrate protein binding at the single particle level. A double nanohole (DNH) optical trap was used to hold onto a 20 nm biotin-coated polystyrene (PS) particle which subsequently is bound to streptavidin. Biotin-streptavidin binding has been detected by an increase in the optical transmission through the DNH. Similar optical transmission behavior was not observed when streptavidin binding sites where blocked by mixing streptavidin with excess biotin. Furthermore, interaction of non-functionalized PS particles with streptavidin did not induce a change in the optical transmission through the DNH. These results are promising as the DNH trap can make an excellent single molecule resolution sensor which would enable studying biomolecular interactions and dynamics at a single particle/molecule level.