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Updated: Jun 18, 2025
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Double Emulsion Generation Using a Polydimethylsiloxane PDMS Co-axial Flow Focus Device
Published on: December 25, 2015
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Drop-by-Drop Addition of Reagents to a Double Emulsion.
Thomas W Cowell1,2, Wenyang Jing3, Heewon Noh1,4
1Department of Chemistry, University of Illinois at Urbana-Champaign, 505 South Matthews Ave, Urbana, IL, 61801, USA.
Small (Weinheim an Der Bergstrasse, Germany)
|August 5, 2024
Summary
This study introduces a method to add reagents to double emulsion (DE) droplets, enabling multistep assays. This breakthrough enhances DE droplet microfluidics for advanced biological research and assay development.
Area of Science:
- Biotechnology
- Microfluidics
- Biochemistry
Background:
- Droplet microfluidics enables high-throughput biological analysis using single emulsion (SE) droplets.
- Double emulsions (DEs) offer advantages like flow cytometry compatibility but lack reagent addition capabilities for multistep assays.
Purpose of the Study:
- To develop strategies for enabling reagent addition and active manipulation within DE droplets.
- To overcome limitations of DEs in multistep assay development.
Main Methods:
- Conversion of DE droplets to SE droplets on-chip for manipulation.
- Utilizing existing SE techniques for reagent addition after conversion.
- Reforming DE droplets at the outlet after manipulation.
- Identifying device designs and conditions for drop-by-drop reagent addition.
Main Results:
- Demonstrated successful on-chip conversion of DEs to SEs and back to DEs.
- Achieved controlled, drop-by-drop reagent addition to DE droplets.
- Successfully performed a multistep aptamer screening assay entirely within DE droplets.
Conclusions:
- This work enables multistep workflows in DE droplet microfluidics.
- The developed strategies significantly expand the utility of DEs for complex biological assays.
- Facilitates further advancements in DE-based assay development and high-throughput screening.
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