Development of a pressure-driven injection system for precisely time controlled attoliter sample injection into...

Area of Science:

• Nanofluidics
• Analytical Chemistry
• Biotechnology

Background:

• Nanofluidics enables analysis of minute liquid volumes (attoliter to femtoliter).
• Decreasing sample sizes are crucial for applications like single-cell analysis.
• Pressure-driven flow in nanofluidics accommodates various solvents (aqueous and organic).

Purpose of the Study:

• To describe an automated injection system for nanofluidic channels.
• To achieve reproducible injection of minimal sample volumes using pressure-driven flow.
• To enhance precision in nanofluidic band analysis.

Main Methods:

• Development of an automated injection system for nanochannels (hundreds of nanometers wide).
• Utilized pressure-driven flow controlled by solenoid valves and a sequencer with 10 ms time resolution.
• Achieved reproducible injection of a minimum 550 aL sample band under normal phase conditions.

Main Results:

• Reproducibly injected minimal sample volumes (550 aL) using the automated system.
• Improved injection reproducibility by one order of magnitude compared to previous methods.
• Enabled accurate determination of injection time zero, crucial for band analysis in nanochannels.

Conclusions:

• The developed pressure-driven flow injection system is versatile for various solvents.
• This system is a significant advancement for nanofluidic applications.
• Potential applications include immunoassays, DNA analysis, and chromatography.