Odorant Sensor Using Olfactory Receptor Reconstituted in a Lipid Bilayer Membrane with Gas Flow System

This work describes a gas flow system for an odorant sensor based on a droplet interface bilayer (DIB) device. In the previous study, the olfactory receptor (OR) was reconstituted in DIB device and odorant, 1-octen-3-ol (octenol), was successfully detected. As a next challenge, we aimed at the continuous monitoring of odorant. Here, we designed a gas flow pathway at the bottom of the droplet forming the bilayer, to effectively absorb the gas into the aqueous phase. The pathway consisted of a microchannel and a slit-structure at the bottom of a well that kept the droplet on top. This gas flow system was integrated as a 16-ch DIB device. By sequentially infusing the octenol gas and air into the channel, we confirmed the increase and decrease of octenol concentration in the droplet. Thus, the designed system was able to absorb and exchange odorant in the droplet. Remarkably, the controlled gas flow stirred inside the droplet, resulting in promoting the gas absorption.