# Non-Stokes Drag Coefficient in Single-Particle Electrophoresis: New Insights on a Classical Problem

## TL;DR

This paper presents experimental measurements of the intrinsic drag coefficient of a charged particle in electrophoresis, revealing significant deviations from classical Stokes drag predictions.

## Contribution

It introduces a novel optical trapping method to measure the intrinsic drag coefficient, challenging the traditional assumptions in electrophoretic drag calculations.

## Key findings

- Intrinsic drag coefficient differs markedly from Stokes drag.
- Optical trapping enables precise measurement of single-particle drag.
- Results suggest revisiting classical models of electrophoretic mobility.

## Abstract

We measured the intrinsic drag coefficient of a single charged particle by optically trapping the particle and applying an alternating electric field, and found it to be markedly different from that of the Stokes drag.

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Source: https://tomesphere.com/paper/1907.11381