“Electronic nose”-type chemosensory systems for detection of gaseous poisonous substances

Abstract

The work is devoted to a study of the detection sensitivity and selectivity of a series of simulants of gaseous poisonous substances (PS). Two different sensor types were used, namely: 1) a quartz crystal microbalance (QCM), exhibiting a shift of the resonant frequency of quartz plates coated with calixarene thin layers, and 2) chemoresistive electrodes coated with layers of nanocomposites of intrinsically conducting polymers (ICP) changing their conductance under the influence of adsorbed gas molecules. The concentration of the analyzed volatile compounds varied within the range of 10 to 1000 ppm. The detection threshold ranged from 10 to 100 ppm depending on the analyzed substance for both transducer types. The response time was from 10 to 20 s for the QCM sensors and up to 1 minute for the ICP based sensors. The possibility of qualitative identification of poisonous substances in a wide concentration range by means of statistical analysis of the sensor array data is demonstrated.