Thread-based isotachophoresis for DNA extraction and purification from biological samples

Area of Science:

• Biotechnology
• Analytical Chemistry
• Molecular Biology

Background:

• Nucleic acid purification is crucial for molecular diagnostics.
• Existing methods can be time-consuming, costly, and require specialized equipment.
• There is a need for rapid, low-cost, and portable nucleic acid isolation techniques.

Purpose of the Study:

• To develop a rapid, low-cost, and disposable microfluidic thread-based isotachophoresis method for nucleic acid purification and preconcentration.
• To enable efficient DNA extraction and analysis using quantitative polymerase chain reaction (qPCR).
• To demonstrate the potential for affordable, thread-based diagnostic devices.

Main Methods:

• Development of a microfluidic thread-based isotachophoresis system for continuous sampling.
• Optimization using a fluorescent dye for preconcentration capacity and speed.
• Application to one-step extraction and preconcentration of lambda DNA from whole blood.
• Assessment of extraction efficiency and PCR inhibitor exclusion.
• Determination of linear range for lambda DNA quantification.

Main Results:

• The method achieved a 600-fold concentration capacity for a fluorescent dye in under 5 minutes.
• Demonstrated efficient one-step extraction of lambda DNA from whole blood with high recovery rates (94.4-113.9%).
• Successfully excluded PCR inhibitors from the sample.
• Established a linear range for lambda DNA determination from 1.0-1 × 105 fg μL-1.
• The system is protein-free and utilizes a continuous sampling approach.

Conclusions:

• The developed microfluidic thread-based isotachophoresis method is effective for nucleic acid purification and preconcentration.
• This technique is rapid, low-cost, and disposable, suitable for point-of-care applications.
• It shows significant potential for developing affordable DNA and RNA isolation platforms for diagnostic devices.