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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.

SUBMITTER: Yukimoto N

PROVIDER: S-EPMC3657717 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Tracking single-particle dynamics via combined optical and electrical sensing.

Yukimoto Naoya N Tsutsui Makusu M He Yuhui Y Shintaku Hirofumi H Tanaka Shoji S Kawano Satoyuki S Kawai Tomoji T Taniguchi Masateru M

Scientific reports 20130101

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 in ...[more]

PMID: 23685401

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