Multilevel fluidic flow control in a rotationally-driven polyester film microdevice created using laser print, cut...

Area of Science:

• Biomedical Engineering
• Microfluidics
• Analytical Chemistry

Background:

• Microfluidic devices offer miniaturized platforms for various applications.
• Cost-effective fabrication methods are crucial for widespread adoption of microfluidic technologies.
• Accurate fluid handling and reagent mixing are essential for reliable bioassays.

Purpose of the Study:

• To develop a simple and cost-effective polyester toner microchip using laser print and cut lithography (PCL).
• To integrate fluid handling, reagent mixing, and assay capabilities onto a single microfluidic platform.
• To demonstrate a proof-of-principle for rapid protein quantification in human blood plasma.

Main Methods:

• Fabrication of a polyester microfluidic disc using laser print and cut lithography (PCL).
• Integration of a battery-powered centrifugal platform for automated fluid handling.
• Incorporation of a surface-tension-driven reciprocating mixer for reagent dilution.
• Development of a 10-minute colorimetric assay for protein level determination.

Main Results:

• The PCL microfluidic disc enabled parallel aliquoting of two reagents in four volumes (nL to μL) with accuracy comparable to piston-driven pipettes.
• A reciprocating mixing unit achieved further reagent dilution.
• The integrated system demonstrated a limit of detection of approximately 5 mg mL(-1) for protein quantification.
• The assay showed a coefficient of variance of approximately 7%.

Conclusions:

• The PCL microfluidic disc combined with a centrifugal platform provides a cost-effective and versatile solution for fluid handling and reagent manipulation.
• The platform is amenable to larger-scale integration for multiplexed assays without significant cost increases.
• This technology offers a promising approach for rapid and accurate point-of-care diagnostics, such as protein quantification in blood plasma.