Open AccessHighly sensitive nano-porous lattice biosensor based on localized surface plasmon resonance and interference
Author(s) -
Se-Hyuk Yeom,
Ok-Geun Kim,
ByoungHo Kang,
Kyu-Jin Kim,
Haiwen Yuan,
Dae−Hyuk Kwon,
HakRin Kim,
ShinWon Kang
Publication year - 2011
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.19.022882
Subject(s) - biosensor , surface plasmon resonance , materials science , nanopore , anodizing , refractive index , nanosensor , biomolecule , colloidal gold , nanotechnology , surface plasmon , plasmon , optoelectronics , nanoparticle , aluminium , metallurgy
We propose a design for a highly sensitive biosensor based on nanostructured anodized aluminum oxide (AAO) substrates. A gold-deposited AAO substrate exhibits both optical interference and localized surface plasmon resonance (LSPR). In our sensor, application of these disparate optical properties overcomes problems of limited sensitivity, selectivity, and dynamic range seen in similar biosensors. We fabricated uniform periodic nanopore lattice AAO templates by two-step anodizing and assessed their suitability for application in biosensors by characterizing the change in optical response on addition of biomolecules to the AAO template. To determine the suitability of such structures for biosensing applications, we immobilized a layer of C-reactive protein (CRP) antibody on a gold coating atop an AAO template. We then applied a CRP antigen (Ag) atop the immobilized antibody (Ab) layer. The shift in reflectance is interpreted as being caused by the change in refractive index with membrane thickness. Our results confirm that our proposed AAO-based biosensor is highly selective toward detection of CRP antigen, and can measure a change in CRP antigen concentration of 1 fg/ml. This method can provide a simple, fast, and sensitive analysis for protein detection in real-time.