Force applied to a single molecule at a single nanogate molecule filter

Abstract

We have investigated the origin of molecule filtering system based on a chemical potential barrier produced by thermodynamically driven molecular flow in a nanoscopic space at nanogates. Single molecule tracking experiments prove that the highly localized potential barrier allows for selective manipulation of the target molecule. We propose the presence of a force, a few fN per molecule, to decelerate the molecule's movement at the nanogate, which is comparable to or larger than the force applied by conventional electrophoretic operation. The present force can be tuned by changing the nanogate width at the nanometre level. These findings allow us to propose an accurate design of novel devices for molecular manipulation on an ultra small scale using a very small number of molecules without any external biases.

Single-molecule observations for determining the orientation and diffusivity of dye molecules in lipid bilayers

“…S1 for MSD plots for each cholesterol concentration). 25,51 The MSD method calculates the diffusion coefficients, D, of the dye molecules in heterogeneous lipid bilayers; the D value for each individual molecule is calculated via linear fitting to the first four points in the corresponding MSD plot according to a previously published method. 25 The D histograms for each cholesterol concentration are shown in Fig.…”

Molecule Manipulation at Electrified Interfaces using Metal Nanogates

“…The advantage of the system with metal nanogate using the self-spreading again becomes apparent from the fact that no external bias is imposed to generate relatively high perturbation applied on molecules. 31 We have also proved that high precision measurements at the single molecule level give novel characteristics of lipid membranes that could not be clarified by other ordinary ensemble measurements. The molecular orientation of molecules was obtained through Electrochemistry, 82(9), 712-719 (2014) defocused imaging under the observation of a single molecule diffusion (Fig.…”

“…2). [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42] The formation of a highly localized compressed phase at the gates acts as the electrochemical potential barrier for the incorporated dye-labeled lipids. The potential barrier reduces the passing ability of dye lipids through the gate, leading to the emergence of the molecular filtering phenomenon.…”

Effective Brownian Ratchet Separation by a Combination of Molecular Filtering and a Self-Spreading Lipid Bilayer System

“…Under this electrolyte condition, singlelipid bilayers, and not multilamellar structures, spontaneously spread from the lipid aggregate to the array region. 27 Determination of Diffusivity of a Single Molecule. The singlemolecule observation for TR-DHPE was conducted using objectivetype total internal fluorescence microscopy (TIRFM) with an IX71 inverted microscope (Olympus).…”