ISBN 9783843954365

978-3-8439-5436-5, Reihe Physik

Franziska Marie Esmek
Development of a Microfluidic Lab-on-a-Chip System for DNA Extraction and Analysis

195 Seiten, Dissertation Universität Hamburg (2023), Softcover, A5

Zusammenfassung / Abstract

The analysis of DNA molecules holds significant importance in various fields, such as forensics, genetics, medicine, and evolutionary biology. The quality of DNA analysis is substantially contingent upon the purity, integrity, and quantity of the sample material, which poses a challenge when dealing with limited sample volumes. To simplify the handling of small sample quantities and ensure higher quality, the current trend is towards integrating extraction from the collected sample and DNA analysis within a single device.

This study presents an integrated micro- and nanofluidic device for on-chip DNA extraction and analysis. It is based on a Lab-on-a-Chip system for on-chip sample preparation and a laser-based analytical method for in-line DNA analysis. The LOC device is fabricated using direct nanoimprinting techniques, allowing the patterning of micro and nano 2D and 3D structures within one device in just one fabrication step. Dose-modulated electron-beam lithography allows for additional complex 3D structuring. External heating elements and magnetic fields add extra functionality to the polymer-based chip, enabling single-use chips while keeping the fabrication simple and low-cost.

The LOC plastic device comprises two integrated sections: the DNA extraction part and the DNA analysis part. In the extraction section, DNA molecules selectively bind to magnetic particles, which can be efficiently transferred into a clean buffer solution using external magnets, thereby purifying the samples. In the analysis section, labeled DNA molecules are stretched within nanochannels and read out using a laser system. The system has been applied for the investigation the DNA flow dynamics in nanochannels in stretching, velocity and throughput. In addition, we showed the proof of concept of using the system for virus identification and the study of genome intercalation in DNA in tumor cells, showcasing the versatility and capabilities of this system.