Love-wave sensor array to detect, discriminate and classify chemical warfare agent simulants

An array made up of Love wave sensors based on quartz/SiO₂ is proposed as a detection system for chemical warfare agents (CWA). The array is composed of one reference and six devices coated with different polymers means of spray coating technique. The system has been tested with well-known CWA simulants: dimethylmethyl phosphonate (DMMP), dipropyleneglycol methyl ether (DPGME), dimethylmethyl acetamide (DMA), dichloroethane (DCE), dichloromethane (DCM), and dichloropentane (DCP), detecting very low concentrations, such as 40 ppb of DMMP, a simulant of sarin nerve gas. Additionally, principal component analysis (PCA) as a data pre-processing and discrimination technique, and probabilistic neural networks (PNN) as a pattern classification technique, have been applied, obtaining a clear discrimination and a correct classification.