Utilisation de nanoparticules plasmoniques pour la biodétection à l'oeil nu d'une toxine
The localized surface plasmon resonance (LSPR) phenomenon provides a versatile property for
biodetection. Herein, this unique feature was employed to build a homogeneous optical biosensor to detect staphylococcal enterotoxin A (SEA) in solution down to very low levels by naked-eye readout. If the initial position of the LSPR band is located in the cyan region, even a small red shift (∼2−3 nm) induced by a refractive index change close to the surface of nanoparticles (NPs) could make the light
absorption transit from cyan to green and become visually detectable via a concomitant change in the complementary colors.
In this work, the authors aimed at synthesizing two types of NPs based on compositionally complex core−shell NPs-Ag shells on AuNPs (Au@AgNPs) and Ag inside gold nanoshells (Ag@AuNPs). By controlling the thickness of the shells and their surface chemistry with anti-SEA antibody (Ab), the LSPR band was tuned to near 495 and 520 nm for Ag@AuNPs and Au@AgNPs, respectively.The two particle systems were subsequently applied to spectroscopically and visually detect anti-SEA Ab−SEA interactions.
KEYWORDS
- Plasmonic nanoparticles
- Gold/silver core−shell
- Biotoxin detection
- Naked-eye readout
- Biosensors
More information on : https://pubs.acs.org/doi/10.1021/acsami.9b14980
DOI : 10.1021/acsami.9b14980
