Portable and easy-to-use insect electroantennography device with mammalian-inspired odor sniffing

The electroantennogram (EAG), an electrical response to odor stimuli in the antennae (olfactory organs) of insects, is a promising odor biosensor that can not only detect species-specific bioactive substances but also detect arbitrary target odors by genetically manipulating the response characteristics of olfactory receptors on the antennae. Therefore, it is necessary to develop a device that is both highly sensitive and easy to use to make odor detection by EAG more practical. In this study, we examined the biological (adult age) and physical (flow speed) factors that improve the overall EAG response, and we developed a portable and easy-to use EAG device. The results showed that in the insects tested (male hawkmoths), while the aging of mature individuals had little effect on the EAG response, the response increased when the flow velocity delivering the odor to the antenna increased. Inspired by mammalian sniffing (active sampling of odors), we developed a 254 g portable EAG device that uses a bellows foot pump to sniff and confirmed its usability by non-experts. These results expand the utility of EAG in odor detection tasks for humans and mobile robots.