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TL;DR

This paper introduces a novel optical fiber platform enabling continuous, high-resolution measurement of single nanoparticle or macromolecule electrophoretic mobility, advancing single-molecule reaction kinetics studies.

Contribution

It presents a highly sensitive nanofluidic optical fiber method for real-time, continuous measurement of single particles' electrophoretic mobility with microsecond resolution.

Findings

Feasibility of measuring single nanoparticle mobility in vitro

Continuous measurement with microsecond time resolution

Potential for studying single-molecule reaction kinetics

Abstract

A highly sensitive optical capillary electrophoresis measurement method based on a nanofluidic optical fiber platform is presented. By using scaling arguments and considering realistic instrument limitations, I underline the feasibility of measuring the electrophoretic mobility of a single freely-diffusing nanoparticle or macromolecule in vitro, continuously and indefinitely, with microsecond time resolution. The high speed of this technique opens up new possibilities for studying reaction kinetics at the single molecule level.