Electronic nose for the detection of organochlorines and polyaromatic hydrocarbons

Halogenated organic compounds and polyaromatic hydrocarbons (PAHs) are traditionally analyzed using gas chromatography with mass spectrometry (GC/MS) and high performance liquid chromatography (HPLC) techniques. However, due to the costs and time involved between sample collection and analysis, in-situ, real-time monitoring techniques are required for on-site characterization. This paper describes the development of multiarray sensors coupled to integrated pattern recognition techniques for the detection of organochlorines and PAHs. The sensor elements consist of an array of thin films having unique fingerprints for each analyte. The output sensor signals were integrated into software-based artificial neural network for the identification of the analytes. The sensor array showed good reproducibility to the different volatile and was classified with respect to the nature of analyte functional groups and physicochemical properties. Classification rates of greater than 98% for achieved for the organochlorines and PAHs.