An Integrated Microfluidic Processor for DNA-Encoded Combinatorial Library Functional Screening.

Area of Science:

• Biochemistry
• Chemical Biology
• Microfluidics

Background:

• DNA-encoded synthesis is regaining prominence for drug discovery and library screening.
• Automated and quantitative screening technologies are crucial for advancing compound library applications.

Purpose of the Study:

• To develop a microfluidic circuit for functional screening of DNA-encoded compound beads.
• To enable automated, quantitative, and high-throughput screening and hit deconvolution.

Main Methods:

• A microfluidic circuit was designed for bead distribution into picoliter droplets, compound cleavage, assay incubation, and fluorescence detection.
• Laser-induced fluorescence and fluorescence-activated droplet sorting were used to isolate hit compounds.
• Next-generation sequencing with template barcoding was employed for hit deconvolution and false discovery rate reduction.

Main Results:

• The platform successfully screened DNA-encoded compound beads for cathepsin D inhibition.
• Initial screening yielded a 24% false discovery rate, which was reduced to 2.6% using sequencing-based hit counting.
• The system demonstrated efficient sorting of hit droplets and accurate deconvolution of bead-encoding sequences.

Conclusions:

• This work establishes a complete, distributable platform for small molecule discovery.
• The microfluidic automation and sequencing-based deconvolution significantly enhance the efficiency and accuracy of DNA-encoded library screening.
• The developed technology offers a powerful tool for ultrahigh-throughput drug discovery.