Microchannel electrophoretic separations of DNA in injection-molded plastic substrates

Area of Science:

• Microfluidics and Lab-on-a-Chip Technology
• Analytical Chemistry
• Biotechnology

Background:

• Traditional fabrication methods for microfluidic devices can be costly and time-consuming.
• There is a need for scalable and cost-effective production of microchip electrophoresis devices.
• High-resolution separation of biological molecules like DNA is crucial for diagnostics and research.

Purpose of the Study:

• To develop a mass-production strategy for microfabricated electrophoretic separation devices.
• To demonstrate the performance of injection-molded chips for high-resolution DNA fragment analysis.
• To assess the reproducibility of these microfluidic devices for practical applications.

Main Methods:

• Fabrication of master templates via solution-phase etching on silicon wafers.
• Electroforming of durable nickel injection-molding masters from silicon templates.
• Mass production of acrylic microchannel chips using injection molding.
• Electrophoretic separation of double-stranded DNA fragments using the fabricated chips.

Main Results:

• Successfully mass-produced microfabricated electrophoretic chips using an injection-molding process.
• Achieved high-resolution separation of double-stranded DNA fragments in under 3 minutes.
• Demonstrated good run-to-run reproducibility (<1% RSD) and chip-to-chip reproducibility (2-3% RSD).

Conclusions:

• Injection molding is a viable method for low-cost, high-volume production of microchip electrophoresis devices.
• These devices offer rapid and reproducible DNA fragment separation, suitable for various analytical tasks.
• The technology holds potential for disposable, single-use chips in applications like DNA sizing, sequencing, and immunoassays.