# Long‐Read, High‐Resolution Sanger Sequencing by Micelle‐Tagging Electrophoresis

## TL;DR

This paper introduces a new electrophoresis method that improves Sanger sequencing read lengths by using micelle-tagging.

## Contribution

The study increases Sanger sequencing fragment length by 280 bases using nonionic micelles as drag-tags.

## Key findings

- MTE achieves 782-base fragment separation, surpassing previous MTE and ELFSE methods.
- C18 alkane groups on primers bind micelles, providing uniform drag for electrophoretic separation.
- A two-parameter time-shifting procedure aligns electropherograms for accurate sequencing.

## Abstract

We demonstrate a gel‐free electrophoretic separation of Sanger sequencing fragments up to 782 bases in length using nonionic wormlike micelles as drag‐tags in micelle‐tagging electrophoresis (MTE). This is an increase of 280 bases over previous MTE methods and a nearly three‐fold improvement over end‐labeled free‐solution electrophoresis (ELFSE) methods that use covalently attached drag‐tags. For MTE, C18 alkane groups are attached to primers prior to their enzymatic extension. This alkane group provides a binding site for wormlike micelles composed of CiEj‐type nonionic surfactants in the running buffer. Transient attachment of micelles to the C18 alkane group provides a highly uniform drag, equal to that of an ssDNA fragment 309 bases long. To account for slight mobility differences among the BigDye chain terminators, we developed a two‐parameter time‐shifting procedure to align the electropherograms for each termination chemistry. The increase in read length for this low‐viscosity buffer (2.1 cP) is attributed to the alignment procedure, the large yet uniform drag, and the small degree of adsorption‐based band broadening.