From Microtiter Plates to Droplets-There and Back Again

Area of Science:

• Biotechnology
• Microfluidics
• Assay Development

Background:

• Droplet-based microfluidics offers advantages for screening but requires integration with existing microtiter plate (MTP) workflows.
• Efficient sample management is crucial for both loading samples into droplets and retrieving them for further analysis.

Purpose of the Study:

• To develop and present a novel bidirectional sampling interface for droplet-based microfluidics.
• To facilitate sample transfer from wells into droplets (w2d) and droplets into wells (d2w) for MTP-based screening.

Main Methods:

• Introduction of Digital Microfluidic Pipetting Tips (DMPTs) with integrated droplet generation and manipulation capabilities.
• Utilizing a robotic system for operating the DMPTs, designed to fit 96-deep-well MTPs.
• Fabrication of DMPTs from glass using microsystems technology, enabling sequential droplet generation with carrier medium and addition of assay compounds.

Main Results:

• Demonstration of DMPTs as a versatile interface for w2d and d2w sample transfer.
• Development of four DMPT variants to support diverse assay protocols, including 2D screening with gradient compositions.
• Successful integration with a robotic system for automated operation.

Conclusions:

• The developed DMPT system provides an effective solution for interfacing droplet microfluidics with MTP-based workflows.
• This technology enhances sample handling efficiency and flexibility in microfluidic screening applications.
• The bidirectional transfer capability supports advanced assay formats and downstream processing.