Related Experiment Video
Updated: Jun 9, 2026
14:16
Fluorescence detection methods for microfluidic droplet platforms
Published on: December 10, 2011
22.4K
Confocal Absorbance-Activated Droplet Sorting (cAADS) for Enzyme Engineering
Abdi Mirgissa Kaba1, Sébastien Gounel1, Thomas Beneyton1
1Centre de Recherche Paul Pascal (CRPP), CNRS UMR 5031, Univ. Bordeaux, 115 Avenue du Docteur Schweitzer, Pessac, 33600, France.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|August 14, 2025
Summary
Confocal Absorbance-Activated Droplet Sorting (cAADS) enables sensitive, high-throughput screening of enzyme variants using absorbance detection. This microfluidic system accelerates enzyme engineering by overcoming limitations of fluorescence-based methods.
Area of Science:
- Biotechnology
- Chemical Engineering
- Microfluidics
Background:
- Directed evolution requires efficient screening of enzyme variants.
- Droplet microfluidics offers high-throughput screening but is limited by assay types.
- Fluorescence-based assays are common, but absorbance assays cover more enzymatic systems.
Purpose of the Study:
- To develop a microfluidic system for sensitive, high-throughput absorbance-based screening of enzyme variants.
- To overcome the sensitivity and throughput limitations of existing droplet microfluidic screening methods.
Main Methods:
- Development of a confocal Absorbance-Activated Droplet Sorting (cAADS) system.
- Utilizing picoliter-scale water-in-oil emulsions as microcompartments for absorbance measurements.
- Demonstration with Bilirubin Oxidase (BOD) and Glucose Oxidase variants.
Main Results:
- Achieved sensitive absorbance measurements at ultrahigh throughput (5.4 kHz) with 10 pL droplets.
- Enabled sorting of 50 pL droplets at frequencies up to 2.6 kHz.
- Demonstrated 99% sorting efficiency for active BOD variants and versatility with Glucose Oxidase.
Conclusions:
- The cAADS system significantly enhances microfluidic screening capabilities for enzyme engineering.
- This technology expands the applicability of droplet microfluidics to absorbance-based assays.
- cAADS offers a versatile and efficient platform for directed evolution and enzyme discovery.
