Multiplexed sensing platform based on magneto-optical SPR for VOC detection

This work describes the development of a fast, sensitive and reliable device for the detection of outdoor and indoor Volatile Organic Compounds (VOCs) based on the Magneto-Optical Surface Plasmon Resonance (MO-SPR). The novelty of the proposed approach is based on the enhancement of the surface plasmon resonance by applying a magnetic field to modulate the optical signal using the transverse magneto-optical Kerr effect leading to improved sensitivity. The device is based on a modular benchtop MOSPR equipment integrated into an SPR platform with imaging capabilities. The detection area consists of a magneto-optical material based on a Co-Au alloy with increased stability and sensitivity previously developed by our group. The sensitivity of the detection area is further augmented by adding a sensing matrix that includes functional nanoparticles with magneto-plasmonic properties. An array of spots of gas-sensitive polymers and metallic oxides embedded in a sensing matrix provides a specific "fingerprint" after interacting with individual VOCs. The measured response is analyzed using a multivariate data analysis approach to extract relevant information regarding the type and quantity of the compound. The device is tested on ethanol, toluene and xylene as model VOCs.