α-Cyclodextrin Functionalized Planar Bragg Grating Sensor for the Detection of Small Arene Traces in Solvent Vapour

摘要

We report on an optical sensor system, which is highly sensitive to small traces of arenes in solvent vapour. The sensor system is based on a planar Bragg grating refractive index sensor which is sensitised towards arenes by applying a thin layer of substituted α-cyclodextrins to the sensor surface by dip coating. In our studies using benzene as a representative of arenes, the dependence of the spectral shift of the reflected Bragg wavelength on variation of the benzene concentration was found to 8 pm/100 ppm. Considering the spectral resolution of the interrogation system with reliable signal identification, this leads to a minimum detectable benzene concentration of 75 ppm.