Extrinsic plasmonic optical fiber sensors based on POFs and bacterial cellulose slab waveguides

We propose a novel extrinsic optical fiber sensor, based on two plastic optical fibers (POFs) combined with a bacterial cellulose (BC) optical waveguide. The POFs connect the green disposable optical sensor with a white light source and with a spectrometer. We have deposited a thin gold film on this innovative slab waveguide for obtaining a Localized Surface Plasmon Resonance (LSPR) sensor. In fact, the deposited thin gold layer is not formed by a continue film and the preliminary experimental results confirm the possibility of using the BC based composite as an environmental friendly optical sensor platform with LSPR capabilities. This approach could be exploited for realizing disposable biosensors, when the green slab waveguide is fixed in a special support. The device has been tested by measuring the refractive index of different water-glycerin solutions.