Drones with electronic noses have been developed by Spanish researchers to measure nuisant odors in purification plants. The electronic nose weighs 1.3 kilo and consists of a box with a small hole through which air is drawn in and a vacuum pump that empties the box after a measurement. The box itself contains 21 gas sensors, which detect ammonia, hydrogen sulphide (the well-known rotten egg smell), methane and 18 other compounds that humans categorize as stinking. These measurements are sent to a computer via WiFi, together with the location, so that the source can be determined. However, this electronic cannot register (yet) which of the compounds and how much of it is in the air. If you want to read more, here is the link.
This news reminded me of the bionose that we have been trying to develop with BSc students to detect the presence of pathogenic yeasts in hospitals, using a combination of different insect antennae as the detector. Insect antennae are much more sensitive than any human-designed chemical instrument, even the most sensitive gas chromatograph or mass spectrometer. When placing an antenna between two electrodes, detection of volatiles can be measured by a change in electropotential that occurs when an odor molecule attaches to the olfactory receptor. As different groups of insects have different olfactory receptors, the students used a combination of 4-5 different insect antennae with which they were able to create a neural network that could distinguish between different yeast species with some accuracy. Unfortunately, I cannot give any link yet, as we haven’t been able to produce enough data for a publication yet. For those who are interested in the development of other bionoses, this may be an interesting further read.
Written by Astrid Groot