Liquid Chromatography Chip with Low-Dispersion and Low-Pressure-Drop Turn Structure Utilizing a...

Area of Science:

• Analytical Chemistry
• Microfluidics
• Separation Science

Background:

• Pillar array columns offer potential for efficient separations but are limited by dispersion and pressure drop in turns.
• Existing turn designs, such as tapered turns, present trade-offs between dispersion and pressure drop.

Purpose of the Study:

• To develop a novel turn structure for pillar array columns that minimizes both sample dispersion and pressure drop.
• To enhance the efficiency and speed of separations in microfluidic devices.

Main Methods:

• A
• pillar-distribution-controlled
• (PDC) turn was designed using octagonal pillars within a constant-radius turn.
• Computational fluid dynamics (CFD) analysis was employed to optimize pillar placement.
• 27 mm long pillar array columns with two PDC turns were fabricated on silicon glass.

Main Results:

• The PDC turns achieved low sample dispersion, comparable to previously developed tapered turns.
• The pressure drop in the PDC turns was reduced to approximately 1/6 of that in tapered turns.
• A C18-modified pillar array column with PDC turns successfully separated five fluorescently labeled amino acids in 24 seconds at a linear velocity of 7.5 mm/s.

Conclusions:

• The developed PDC turn structure effectively reduces pressure drop and sample dispersion in pillar array columns.
• This design facilitates the creation of longer pillar array columns with more turns for rapid analysis of complex samples.
• The PDC turns demonstrate significant potential for advancing bioanalytical applications requiring fast and efficient separations.