Self-Spreading Behavior of Supported Lipid Bilayer through Single Sub-100-nm Gap

Abstract

We report on the self-spreading behavior of a supported lipid bilayer passing through a sub-100-nm gap (nanogap). For this purpose, a device with a nanogap in a microchannel on a silicon substrate was designed and fabricated by electron beam lithography and photolithography. Fluorescence images of the lipid bilayer labeled with dye-conjugated lipids were observed by using a confocal laser scanning microscope. The time evolution of the self-spreading lipid bilayer passing through the nanogap was investigated at first. In the device, the lipid bilayer successfully passed through the nanogap without any stagnation. An analysis of the velocity of an advancing lipid bilayer showed no significant effect before or after passage though the nanogap. The effects of dye-conjugated lipid molecules and the size of the nanogap on the self-spreading behavior were examined next. We observed an abrupt decrease in the fluorescence intensity in the vicinity of the nanogap with Texas Red-DHPE and fluorescein-DHPE. It was revealed that the decrease depends on nanogap size as well as bulkiness of the dye molecule. The results suggest that bulkier dye molecules experience interference when they pass through narrower nanogaps.

Control of Supported Lipid Bilayer Self-Spreading through Nanogap by Local Electric Field

“…A red fluorescent single lipid bilayer developed along a microchannel from the left side. We confirmed that the lipid bilayer did not develop on the photoresist or gold pattern but only on the hydrophilic SiO 2 surface [8]. In all the present experiments, the lipid bilayer passed through a nanogap with a semicircular shape without electric field applied on the nanogap.…”

“…We have demonstrated some interesting features of supported lipid bilayers that derive from the self-spreading nature of the lipid bilayer, including the observation of fluorescence resonance energy transfer [7] and the effect of a nanogap structure on the membrane [8,9]. In this study, we investigated the way that an electric field applied to a single nanogap affects the dynamics of lipid bilayers passing through the nanogap.…”

Examination of Ion Channel Protein Orientation in Supported Lipid Bilayers

“…We have been trying to fabricate ''nano-biodevices'' by combining Si substrates possessing nanoscale features with biomolecules (i.e., lipids and ion channels). [1][2][3][4] Recently, we have demonstrated that suspended lipid bilayers (SsLBs) can be successfully and stably formed over micro-wells with an optimal substrate architecture. 5) As the next step, we examined the regulation of the ion channel protein orientation in lipid bilayers.…”

Supported Lipid Bilayer Composition Microarray Fabricated by Pattern-Guided Self-Spreading

“…This highly integrative SLB microarray fabrication technique is advantageous for use with high-throughput device architecture. Because SLB is known to self-spread through a sub-100-nm gap, 27 we can extend our technique to submicrometer arrays by using an electron beam lithography pattern that has the potential to increase the integration density by 10 2 compared with previously reported methods. We think that the composition submicroarrays can provide opportunities for previously impractical experiments.…”