Artificial cell membrane system for odorant sensor: development of solution exchange driven by superabsorbent polymer for repeatable detection

This paper describes an odorant sensor based on artificial cell membrane device integrated with a system of solution exchange for repeatable odorant detection. The olfactory receptor (OR) was reconstituted in the membrane on the developed device and the target odorant, 1-octen-3-ol, was detected by the opening current of the ionotropic receptor (OR). Solution exchange, which is to refresh the absorbed odorant from OR, was implemented by continuous flow of a buffer solution, driven by suction force of superabsorbent polymer. Note that no electricity is required for the exchange system. To demonstrate the solution exchange, a biological nanopore was reconstituted in the membrane, and blocking phenomena was observed using hepta-6-sulfato-β-cyclodextrin. The frequency of current steps that correspond to blocking of the nanopore decreased over the solution exchange. We believe that this solution exchange system is applicable to the odorant sensor based on artificial cell membrane and realizes repeatable odorant detection.