A high-density integrated odorant sensor array system based on insect cells expressing insect odorant receptors

We have demonstrated the first parallel detection of electrical signals caused by odorant responses of insect cells expressing insect odorant receptors with a 64 χ 64 complementary metal-oxide semiconductor (CMOS) monolithically integrated sensor array with surface-oxidized gate electrodes. The individual sensor element transduces odorant responses of cells contacting with each electrode into an electrical signal, which is confirmed by the corresponding fluorescence. Therefore, a high-density sensor array based on different insect OR-expressing cells could be used to make an artificial olfactory system that discriminates various odorants simultaneously, as do natural olfactory systems.