Noise Analysis of Si-Based Planar-Type Ion-Channel Biosensors

Abstract

A micropore with a diameter of 50–100 µm was formed, which penetrated a silicon on insulator (SOI) substrate and a Teflon substrate. The single-ion-channel current of gramicidin A (g-A) was measured for the planar lipid bilayer with reconstructed g-A formed in this micropore. The background noise in the SOI substrate was almost at an equivalent level to that in the Teflon substrate. It can be concluded from the noise analysis that a noise characteristic of the same level as that of the Teflon substrate or the glass substrate can be achieved for the Si substrate by controlling the substrate structure in the vicinity of the micropore with a wide range of pore diameters.

A Cell-Culture-Type Planar Ion Channel Biosensor

“…We succeeded to reduce the noise current by using a P-type silicon-on-insulator (SOl) substrate with 50-75 Qcm resistivity. The SOl substrate is composed 4 ± 0.2 ~m SOl layer and 3 ± 0.5 ~m Si0 2 layer [8].…”

Si based Planer Type Ion-channel Biosensor and Its Applications

“…From this point, there is some disadvantage in Si, for which low resistivity of Si easily gives a large capacitance. However, in recent investigations, we have shown that the parasitic capacitance can be reduced to almost equivalent to the Teflon chip, by controlling the oxide layer structure around the micro pore [1]. Concerning the noise (c), the most im-portant challenge is to increase the seal resistance.…”

Noise Properties of Incubation-Type Planar Ion Channel Biosensor

“…5,6) Noise properties are the most important issues in ion channel biosensors, and they have been investigated in detail in pipette patch-clamp and black membrane biosensors, in which high seal resistance (>G) exists between the membrane and the pipette. 7,8) The noise properties of planartype ion channel biosensors, where seal resistance is relatively low, however, to the best of our knowledge have never been investigated, despite on their significance.…”