Personal ammonia sensor for industrial environments

The realisation of an opto-chemical ammonia sensor suitable for personal mo nitoring tasks is described, comprising a cyanine dye immobilised in a micr oporous glass thin him. The fabrication of sensor platforms incorporating e mbossed grating couplers provides a compact optical design with effective w aveguiding characteristics, resulting in reversible ammonia sensitivity in the 5-100 ppm range in under 2 min. Cross-sensitivity of sensor response wi th water and other potential interferents is considered.