title: Tracking single-particle dynamics via combined optical and electrical sensing.
abstract: While fluorescent imaging has been extensively used for single-particle tracking, temporal and spatial resolution of the wide-field microscopy technology is not satisfactory for investigating fast-moving features. Here we report a method for probing nanometer-scale motion of an individual particle through a microstructured channel at sub-MHz by combining a resistive pulse technique to the optical sensing. We demonstrate unambiguous discriminations of translocation and non-translocation events inferred from spike-like electrical signals by fluorescence images captured synchronously to ionic current measurements. We also find a trajectory-dependent translocation dynamics of voltage-driven single-particles through a microchannel. This electrical/optical approach may find applications in sensor technologies based on micro- and nano-electromechanical systems.
authors.affiliation: The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Yukimoto
authors.forename: Makusu
authors.initials: M
authors.lastname: Tsutsui
authors.forename: Yuhui
authors.initials: Y
authors.lastname: He
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Shintaku
authors.forename: Shoji
authors.initials: S
authors.lastname: Tanaka
authors.forename: Satoyuki
authors.initials: S
authors.lastname: Kawano
authors.forename: Tomoji
authors.initials: T
authors.lastname: Kawai
authors.forename: Masateru
authors.initials: M
authors.lastname: Taniguchi
mesh_terms: D017097:Electric Impedance; D004563:Electrochemistry; D057446:Hydrodynamics; D007473:Ion Channels; D044085:Microfluidics; D053758:Nanoparticles / Q000737:chemistry*; D055096:Optical Devices
chemical_list: D007473:Ion Channels