Rapid nanoliter DNA hybridization based on reciprocating flow on a compact disk microfluidic device

Area of Science:

• Biotechnology
• Microfluidics
• Molecular Diagnostics

Background:

• DNA hybridization assays are crucial for diagnostics but often require significant time and sample volumes.
• Microfluidic devices offer miniaturization and improved reaction kinetics for biological assays.

Purpose of the Study:

• To develop a compact disk (CD) microfluidic device for rapid DNA hybridization.
• To demonstrate the efficacy of a reciprocating flow mechanism for enhancing DNA hybridization efficiency.
• To enable DNA testing using nanoliter-volume samples.

Main Methods:

• Fabrication of a polydimethylsiloxane (PDMS) CD microfluidic device with integrated DNA hybridization units.
• Generation of reciprocating flow via a rotation-pause operation utilizing centrifugal and capillary forces.
• Performance evaluation using Dengue virus gene sequence for DNA hybridization assay.

Main Results:

• The CD microfluidic device successfully generated reciprocating flow for DNA samples.
• Reciprocating flow significantly enhanced mass transfer, reducing DNA hybridization time to 90 seconds.
• Nanoliter sample volumes were sufficient for each assay unit.
• Reciprocating-flow hybridization showed up to a threefold increase in fluorescence intensity compared to flow-through methods.

Conclusions:

• The developed CD microfluidic device enables rapid DNA hybridization assays with minimal sample volumes.
• The reciprocating flow strategy is highly effective in accelerating hybridization kinetics.
• This technology holds potential for automated, rapid, and multiplexed DNA-based diagnostic applications.