Electronic Nose: Current Status and Future Trends

Institute of Physical and Theoretical Chemistry, University of Tübingen, Auf der Morgenstelle 15, Tübingen, Germany.
Chemical Reviews (Impact Factor: 46.57). 03/2008; 108(2):705-25. DOI: 10.1021/cr068121q
Source: PubMed


The development of the electronic nose have paved the way for the classification of bacteria, to monitor air quality on the space shuttle, or to check the spoilage of foodstuff. However, the electronic nose still is unable to discriminated between flavors, perfumes, smells and as a replacement for the human nose. Although it has been used to detect some important nonodorant gases, it is not adapted to substances of daily importance in mammalian life such as the scent of other animals, foodstuff or spoilage. Due to such limitations, the electronic nose was developed to mimic the human nose. It turns out that the human nose's unequaled performance is not due to the high number of different human receptor cells, but their selectivity and their unsurpassed sensitivity for some analyte gases. As such, the success of the electronic nose will not rely on increasing the number of individual sensors and creating redundant information by adding more similar sensors, but rather on DNA, molecular, imprinted molecules or even mobilized natural receptors, which promise to increase the sensitivity and importantly selectivity. An increase in the sensitivity can be achieved by appropriate sample pretreatment and preconcentration techniques, whereas filters and separation units can be used to increase the selectivity and reduce interfering substances.

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    Carbon 09/2015; 91:178-187. DOI:10.1016/j.carbon.2015.04.082 · 6.20 Impact Factor
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    Sensors and Actuators B Chemical 08/2015; 215. DOI:10.1016/j.snb.2015.03.103 · 4.10 Impact Factor
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    • "Electronic noses [1] [2] mimic the mammalian olfactory system, and they are usually composed of two important components: the chemical-sensing system and the pattern-recognition system. However, the discrimination ability of man-made electronic noses is presently highly limited compared with that of mammalian noses [3] [4]. Nevertheless, because electronic noses are sensitive, fast and easy to operate, researchers have attempted to apply them to many fields, such as disease diagnosis [5] [6] [7], the detection of explosives [8], and food safety control [9] [10]. "
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