Microfluidic Formation of Double-Stacked Planar Bilayer Lipid Membranes by Controlling the Water-Oil Interface

Abstract

This study reports double-stacked planar bilayer lipid membranes (pBLMs) formed using a droplet contact method (DCM) for microfluidic formation with five-layered microchannels that have four micro guide pillars. pBLMs are valuable for analyzing membrane proteins and modeling cell membranes. Furthermore, multiple-pBLM systems have broadened the field of application such as electronic components, light-sensors, and batteries because of electrical characteristics of pBLMs and membrane proteins. Although multiple-stacked pBLMs have potential, the formation of multiple-pBLMs on a micrometer scale still faces challenges. In this study, we applied a DCM strategy to pBLM formation using microfluidic techniques and attempted to form double-stacked pBLMs in micro-meter scale. First, microchannels with micro pillars were designed via hydrodynamic simulations to form a five-layered flow with aqueous and lipid/oil solutions. Then, pBLMs were successfully formed by controlling the pumping pressure of the solutions and allowing contact between the two lipid monolayers. Finally, pore-forming proteins were reconstituted in the pBLMs, and ion current signals of nanopores were obtained as confirmed by electrical measurements, indicating that double-stacked pBLMs were successfully formed. The strategy for the double-stacked pBLM formation can be applied to highly integrated nanopore-based systems.

Microfluidic Formation of Honeycomb-Patterned Droplets Bounded by Interface Bilayers via Bimodal Molecular Adsorption

“…We fabricated the microfluidic device as illustrated using standard photolithography processes [ 28 , 29 ] with a photoresist, SU-8 3025. Film photomasks were designed using two-dimensional computer-aided design (2D-CAD) software (AutoCAD 2014, AUTODESK, San Francisco, CA, USA) and fabricated with a laser spot diameter and drawing pitch of 4 and 1 μm, respectively.…”

Recent Advances in Liposome-Based Molecular Robots

“…As shown above, a combination of nanopore technologies and DNA computing could therefore facilitate the sensory function of molecular robots. [90]. (e) Lipid bilayer formation and channel current recording using an Ag/AgCl microelectrode.…”

“…Reproduced with permission from [92]. [90]. (e) Lipid bilayer formation and channel current recording using an Ag/AgCl microelectrode.…”

Parallel Recordings of Transmembrane hERG Channel Currents Based on Solvent-Free Lipid Bilayer Microarray

“…In BLM reconstitution systems, free-standing BLMs are commonly suspended in micro-apertures fabricated in plastic films [ 17 , 18 , 19 ], glass pipettes [ 20 , 21 , 22 ], and microstructured silicon nitride (Si 3 N 4 )/silicon (Si) septa [ 15 , 23 , 24 ]. Although decreasing the size of the aperture significantly improves the stability of BLMs, incorporating ion channels into smaller BLMs becomes more difficult [ 18 , 25 ].…”

“…Non-volatile organic solvents have been frequently used to stabilize BLMs [ 1 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ]. The solvent seals the gap between the nanometer-thick BLMs and aperture walls, and it allows lipid molecules to align in an appropriate orientation.…”