Real-time vapour sensing using an OFET-based electronic nose and genetic programming
Wedge DC., Das A., Dost R., Kettle J., Madec MB., Morrison JJ., Grell M., Kell DB., Richardson TH., Yeates S., Turner ML.
Electronic noses (e-noses) are increasingly being used as vapour sensors in a range of application areas. E-noses made up of arrays of organic field-effect transistors (OFETs) are particularly valuable due the range and diversity of the information which they provide concerning analyte binding. This study demonstrates that arrays of OFETs, when combined with a data analysis technique using Genetic Programming (GP), can selectively detect airborne analytes in real time. The use of multiple parameters - on resistance, off current and mobility - collected from multiple transistors coated with different semiconducting polymers gives dramatic improvements in the sensitivity (true positive rate), specificity (true negative rate) and speed of sensing. Computer-controlled data collection allows the identification of analytes in real-time, with a time-lag between exposure and detection of the order of 4 s. © 2009 Elsevier B.V. All rights reserved.