Optical fiber gratings: hybrid gold structures for immunoassays

Biosensing using optical fibers allows the detection of low concentrated analyte, bringing point-of-care and remote analyses. Tilted fiber Bragg gratings (TFBGs) are permanent structures photo-inscribed inside the core of telecommunication-grade optical fibers and are known to be highly sensitive refractometers. In this paper, we present a hybrid gold deposition method to monitor thin depositions in real time though the inherent properties of the spectra. This yield Surface Plasmon Resonance (SPR) enhancements that is of interest for the detection of low concentrations of analytes. We show how to functionalize our sensors against proteic biomarkers. This strategy is one of a series to manufacture TFBGs platforms adapted for biosensing.