Open AccessLabel-free antibody detection using band edge fringes in SOI planar photonic crystal waveguides in the slow-light regime
Author(s) -
Jaime García-Rupérez,
V. Toccafondo,
MaríaJosé Bañuls,
Javier García Castelló,
Amadeu Griol,
Sergio Peransi-Llopis,
Ángel Maquieira
Publication year - 2010
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.18.024276
Subject(s) - photonic crystal , refractive index , optics , materials science , waveguide , detection limit , planar , biosensor , silicon on insulator , total internal reflection , bovine serum albumin , optoelectronics , physics , silicon , chemistry , nanotechnology , biochemistry , computer graphics (images) , chromatography , computer science
We report experimental results of label-free anti-bovine serum albumin (anti-BSA) antibody detection using a SOI planar photonic crystal waveguide previously bio-functionalized with complementary BSA antigen probes. Sharp fringes appearing in the slow-light regime near the edge of the guided band are used to perform the sensing. We have modeled the presence of these band edge fringes and demonstrated the possibility of using them for sensing purposes by performing refractive index variations detection, achieving a sensitivity of 174.8 nm/RIU. Then, label-free anti-BSA biosensing experiments have been carried out, estimating a surface mass density detection limit below 2.1 pg/mm2 and a total mass detection limit below 0.2 fg.