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We propose a batch fabrication of a perforated separator for formation of a planar lipid bilayer, aiming for commercial and mass production. A planar lipid-bilayer system increasingly attracts attention as a platform of nanopore-based biosensors, and a perforated separator is an essential component for reconstitution of a planar bilayer on such sensor devices. We therefore designed a mass-fabrication procedure of the separator, avoiding laborious processes. First, an array of microapertures was processed on a sheet of polyimide thin film (200 × 200 mm2) by chemical etching. Photo-reactive polyimide coverlays were then laminated and formed a frame of the apertures at both faces of the film as reinforcement. Approximately 300 pieces of monolithic separators were obtained by the procedure. Electrical properties (current noise level) of a planar bilayer were certified with the developed separator.

This paper shows a fabrication of a shallow chamber device for formation of bilayer lipid membranes (BLMs). The chamber device is composed of microperforated polytetrafluoroethylene thin film, and two magnetic rings that work as both electrodes and the chamber walls. Comparing to conventional open chamber devices for BLM formation that is based on droplet contact method, our approach can reduce the water depth, and it becomes that much easier to access the BLM via liquid ab extra. We confirmed that the formed membrane was BLM using membrane protein that made nanopore in BLMs. In addition, gas chromatographic analyses implied that adsorption of odorant into the buffer solution was more effective at shallower water level than deep position. We expect that this shallow chamber is potentially useful for odorant sensing based on olfactory receptors reconstructed in BLMs.

This paper describes a formation of asymmetric lipid vesicles with a size range of 100–400 nm in diameter, using an improved jetting method based on a microfluidic technology. When jet flow was applied to a planar lipid bilayer formed by a droplet contact method, nano-sized vesicles (100–400 nm in diameter) were found by a transmission electron microscopy (TEM). We also confirmed the generation of nano-sized asymmetric lipid vesicles by binding a gold colloid.

We propose a nanopore-based vapor biosensor, utilizing a breathable fabric for rapid detection. Vapor permeated through the fabric, bound to DNA aptamer, and was detected by nanopore sensing schematic. As the fabric suppressed the evaporation of liquid, the liquid height was set to 1 mm, and enabled the absorption and detection of vaporized pesticide (omethoate), within 23 s after exposure. This device holds the compatibility of vapor absorption and evaporation tolerance, which would improve the response time and durability of vapor biosensors in future.

This paper describes the development of a handheld device for long-term nanopore-based biosensing. Recently, membrane protein reconstituted in bilayer lipid membrane (BLM) has been applied for bio/chemical sensors because membrane protein intrinsically has a superior amplification mechanism. For mobile use of such devices, however, the bilayer requires mechanical robustness. Here, we propose a handheld BLM device aiming for a nanopore-based mobile sensor. BLM is formed at the tip of a glass capillary, which is contained in the solution trapped in a cup-like reservoir. This format achieved (i) formation of a sufficiently robust BLM for mobile use, (ii) solution exchange without rupturing BLM, and (iii) sustaining the small number of nanopores in the bilayer for accurate and long-term sensing. The handheld device successfully detected DNA translocations through the nanopores continuously for 75 minutes using 5 nanopores.