An integrated digital microfluidic lab-on-a-chip for clinical diagnostics on human physiological fluids

Area of Science:

• Biomedical Engineering
• Microfluidics
• Analytical Chemistry

Background:

• Microfluidic lab-on-a-chip systems offer promise for point-of-care clinical diagnostics.
• Conventional continuous-flow microfluidics lack reconfigurability and scalability for real-world samples.
• Handling diverse human physiological fluids presents a significant challenge for current microfluidic devices.

Purpose of the Study:

• To present a novel, reconfigurable droplet-based digital microfluidic lab-on-a-chip system.
• To demonstrate the compatibility of various human physiological fluids with the electrowetting platform.
• To validate the system's feasibility for performing quantitative bioassays on real clinical samples.

Main Methods:

• Utilized electrowetting for microdroplet manipulation on a digital microfluidic platform.
• Tested compatibility with human whole blood, serum, plasma, urine, saliva, sweat, and tears.
• Performed colorimetric enzymatic glucose assays on serum, plasma, urine, and saliva.

Main Results:

• Demonstrated reliable, high-speed transport of diverse microdroplets of physiological fluids.
• Achieved comparable glucose concentration results to reference methods for serum, plasma, and saliva.
• Identified uric acid interference in urine samples, leading to significant concentration differences.

Conclusions:

• The developed digital microfluidic system is compatible with a wide range of physiological fluids.
• The platform shows feasibility for automated, integrated clinical diagnostics at the point-of-care.
• Further development is needed to address matrix effects, such as interference from uric acid in urine.