Microfluidic device architecture for electrochemical patterning and detection of multiple DNA sequences

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Nanotechnology

Background:

• Electrochemical biosensors offer advantages for point-of-care diagnostics due to minimal instrumentation and scalability.
• Integrating electrochemical biosensors with microelectronics faces challenges related to biomolecular stability, sensor operation, and microfabrication.
• Existing methods lack integrated solutions for the complete biosensing workflow within microfluidic devices.

Purpose of the Study:

• To develop a novel electrochemical array architecture for integrated biosensing within a self-enclosed microfluidic device.
• To overcome the limitations of current electrochemical biosensor integration with microscale devices.
• To demonstrate a versatile platform applicable to various biosensing schemes, including gold-thiol self-assembled monolayer chemistry.

Main Methods:

• Developed a self-enclosed microfluidic device housing an electrochemical array.
• Implemented in situ processes including electrode cleaning, preparation, and immobilization of sensing biomolecules.
• Utilized electrochemical addressing and patterning for selective biomolecule placement.
• Performed sequence-specific electrochemical detection and pixel regeneration.

Main Results:

• Successfully demonstrated an electrochemical array architecture supporting multiple in situ processes.
• The architecture is general and compatible with gold-thiol self-assembled monolayer chemistry.
• Proof-of-principle detection and differentiation of H1N1 and H5N1 influenza polymerase chain reaction (PCR) amplicons were achieved.

Conclusions:

• The developed electrochemical array architecture effectively integrates biosensing processes within a microfluidic device.
• This platform offers a scalable and versatile solution for point-of-care diagnostics.
• The technology shows promise for rapid and specific detection of various nucleic acid targets, exemplified by influenza strain differentiation.