Quad Lipid Bilayer Module with 1-GΩ Series Resistors Toward Quantitative Stochastic-Biosensors

This work designs and demonstrates the lipid bilayer-based ultra-sensitive biosensor capable of short-time detection in a quantitative manner, which is achieved by connecting multiple sensor elements in parallel. Artificial cell membranes with functional membrane proteins can form sensitive/selective biosensors. But the sensors suffer lengthy detection time at low concentration of analytes because the sensing mechanism relies on stochastic phenomena. In this work, we connected independent membrane sensors in parallel, where the ionic current through the multiple membranes was monitored by a single detector. With this format, the detection time is shortened based on the number of the array and the sensing can be quantitative. We developed a quad sensor assembling four membranes in parallel, and examined detection time of a single membrane sensor, the quad sensor, and four parallel quad-sensors. 1-GΩ resistor was installed in series with each membrane to avoid overload current caused by membrane rupture. The results showed significant improvement in the detection time and deviation by the parallelization, which promises quantitative monitoring with the stochastic sensor.