# Development of a Low-Cost and Easy-Assembly Capillary Electrophoresis System for Separation of DNA

## TL;DR

Researchers developed a low-cost, easy-to-assemble capillary electrophoresis system for DNA analysis that performs reliably and can be built for under $1100.

## Contribution

A compact, low-cost, and flexible CE-LIF system was developed with demonstrated stability and performance for DNA separation.

## Key findings

- The system achieved a relative standard error of less than 6.2% for fluorescence intensity and 1.1% for migration time.
- The detection limit for dsDNA was as low as 0.05 ng/μL with a working range of 0.05 ng/μL to 10 ng/μL.
- The system successfully separated PCR products of Porphyromonas gingivalis and Candida albicans.

## Abstract

Capillary electrophoresis based on laser-induced fluorescence (CE-LIF) plays an important role in the analysis of nucleic acids. However, the commercial CE-LIF is not only quite expensive but also inflexible, thus hindering its widespread use in the lab. Herein, we proposed a compact, low-cost, and flexible CE-LIF system. We also investigated its stability by separating the DNA ladders. Experiments demonstrated that the relative standard error of the relative fluorescence intensity and migration time was lower than 6.2% and 1.1%, respectively. The aperture size of the light source illuminating the capillary can affect the separation performance. Smaller apertures offer higher resolution length for the adjacent DNA fragments but may reduce the number of theoretical plates. Various fluorescent dyes (e.g., SYBR Green I, Gel Green, EvaGreen) can be employed in the self-built system. The limit of detection of dsDNA was as low as 0.05 ng/μL. The working range for DNA was 0.05 ng/μL~10 ng/μL. Finally, we have successfully separated the PCR products of the target gene of Porphyromonas gingivalis and Candida albicans in the home-built CE system. Such a robust CE-LIF system is easy to assemble in the lab. The total cost of the assembled CE system did not exceed 1100 USD. We believe this work can advance the application of CE and hope it will facilitate the easy assembly of flexible CE instruments in labs.