Development of an optical fibre-based plasmonic sensor for specific detection of target biomolecules

We report on the development of an optical fibre-based plasmonic sensing platform for specific detection of target biomolecules. The sensing platform uses a U-bent optical fibre covered with a monolayer of chemically synthesized triangular nanoprisms-shaped gold nanoparticles. The sensor relies on the refractive index dependent shift of the surface plasmon resonance (SPR) wavelength of the nanoparticles upon binding with the target molecules. The chemical fabrication process was optimized to tune the SPR wavelength of the nanoparticles to NIR wavelengths for optimized refractive index sensitivity. The nanoprisms were deposited on the fibre via directly dip-coating in nanoparticle solution. A portable CCD-spectrometer was used to measure the SPR wavelength shift.