We have fabricated a planar type ion channel biosensor useful for the high throughput screening by using SOI (Silicon On Insulator) substrates. The micro-pore of about 1μm diameter was formed through the SOI substrate and controlled the structure of the pore. The substrate was assembled into the micro fluid circuit. Comparing with classical patch-clamp using the pipette, the planar type patch-clamp has advantages not only in the miniaturization and the high integration, but also in easiness of intracellular fluids exchange and of simultaneous measurement of ion channel current and fluoresce imaging. The HEK293 (Human Embryonic Kidney 293) cell with transfected TRPV1 (transient receptor potential vanilloid type 1) channels, which are mainly expressed in sensory nerve cells, was positioned on the micro-pore, and the capsaicin, which is a pungent ingredient of the hot pepper, was added to the external cell solution as a ligand molecule, then the whole-cell current of the ion channel was measured.
