Rapid Nucleic Acid Extraction and Purification Using a Miniature Ultrasonic Technique.

Area of Science:

• Biotechnology
• Microfluidics
• Biomedical Engineering

Background:

• Traditional biological sample preparation methods for nucleic acid and protein extraction can be time-consuming and may involve harsh chemicals that interfere with downstream assays.
• Acoustic lysis offers a rapid, chemical-free alternative for efficient cell membrane disruption.

Purpose of the Study:

• To present a miniature acoustic nucleic acid extraction system utilizing a bulk acoustic wave (BAW) transducer array.
• To evaluate the lysis effectiveness and optimize parameters like input power, energy dose, and flow rate.
• To demonstrate on-chip DNA purification using various methods within microfluidic cartridges.

Main Methods:

• Development of a miniature BAW transducer array using 36° Y-cut lithium niobate.
• Integration of the BAW transducer with disposable laminate-based microfluidic cartridges.
• Assessment of lysis effectiveness via adenosine triphosphate (ATP) release and cell viability measurements.
• On-chip DNA purification using silica-based sol-gel, magnetic beads, and Nafion-coated electrodes.

Main Results:

• The miniature BAW array demonstrated a 2.2× greater lysis dose (ATP released per joule) and 6.1× higher ATP release compared to a bench-top acoustic lysis system using E. coli.
• An electric field-based nucleic acid purification method using Nafion films achieved 69.2% extraction efficiency in 10 minutes for 50 µL samples.
• Established relationships between input power, energy dose, flow rate, and lysis efficiency.

Conclusions:

• The miniature acoustic lysis system provides a highly efficient and rapid method for biological sample preparation.
• On-chip DNA purification strategies integrated within the microfluidic cartridges are effective.
• This technology holds promise for advancing rapid, point-of-care molecular diagnostics and sample preparation.