A novel headspace integrated E-nose and its application in discrimination of Chinese medical herbs

A novel headspace integrated E-nose based on metal oxide gas sensor arrays is reported. And its performance to distinguish six groups of Chinese medical herbs which might be mixed easily by appearance is presented. The headspace integrated E-nose is mainly consisted of gas sensing module, signal procession module and human-machine interaction module. The E-nose, integrated with an innovative headspace diffusion sampling way, has a compact structure with an approximate size of Phi 48 x 100 mm. For the characteristics of the small size and the headspace diffusion sampling way, it is suitable for on-site volatiles analysis in food and raw material detection. Temperature modulation technology was combined with pattern recognition analysis to enhance the selectivity of the E-nose. Principal components analysis and Sammon mapping were used in the feature extraction, while the sample was discriminated by Fisher discriminant analysis. The correct classification rate of the headspace integrated E-nose for discriminating thirteen species of herbs is 100%, which shows the potential application of the E-nose for on-site volatiles analysis. (C) 2015 Elsevier B.V. All rights reserved.