Characterization of a Centrifugal Microfluidic Orthogonal Flow Platform

Area of Science:

• Biotechnology
• Microfluidics
• Analytical Chemistry

Background:

• Centrifugal microfluidics offers advantages for automated immunoassays.
• Orthogonal flow (OF) through membranes is crucial for vertical flow immunoassays.
• Previous work established an OF platform for automated enzyme-linked immunosorbent assays (ELISAs).

Purpose of the Study:

• To develop and characterize a centrifugal orthogonal flow (cOF) system for vertical flow immunoassays.
• To leverage microfluidics for precise control of fluid dynamics through nanoporous membranes.
• To demonstrate the feasibility of antigen capture and immunodetection using the cOF platform.

Main Methods:

• Utilized the print-cut-laminate (PCL) method for rapid disc fabrication and permanent membrane sealing.
• Employed rotational forces for fluid propulsion, replacing capillary action and pneumatic systems.
• Investigated membrane behavior and fluid flow patterns using high-speed videography.

Main Results:

• Demonstrated a robust method for integrating nanoporous membranes into microfluidic discs without solvents.
• Identified key factors influencing membrane behavior and fluid drainage, including sample volume, pore size, and ionic composition.
• Successfully performed proof-of-principle sandwich-type antigen capture and immunodetection assays on prototype cOF discs.

Conclusions:

• The cOF system provides an effective platform for centrifugal microfluidic vertical flow immunoassays.
• The PCL fabrication method enables reliable membrane integration and flow control.
• This technology has potential for automated, high-performance immunoassays.