SUTD researchers discover fluorescence-activated sorting at single-droplet level using focused sound waves

04 Dec 2019 Engineering Product Development Computer Science, Engineering, Nanotechnology

SUTD- Peixian Li, Zhichao Ma, Yinning Zhou, Ye Ai
University of Melbourne- David J. Collins
SIMTech- Zhenfeng Wang

SUTD researchers developed a new microfluidic fluorescence-activated droplet sorting system that can isolate single-cell droplets with high accuracy and high yield using a detachable surface acoustic wave transducer. This novel microfluidic system can be readily integrated with droplet-based single-cell sequencing platform to achieve highly efficient single-cell genetic analysis.
In recent years, rapid progress in the development of single-cell sequencing has provided numerous important insights for understanding the functionality and variation within cell types. Droplet-based microfluidic system has emerged as a very powerful and effective tool to isolate and analyze biological cells at the single-cell level. However, existing droplet generation is a random process that captures cells at a single-cell encapsulation rate of generally lower than 5%. Hence, there is a great need to develop a platform which can isolate single-cell droplets at high yield.
In this study, a Singapore University of Technology and Design (SUTD) research team led by Associate Professor Dr Ye Ai has developed a detachable acoustophoretic system for fluorescence-activated sorting at single-droplet level to detect and isolate single-cell encapsulated droplets at high accuracy and yield.
The developed fluorescence-activated droplet sorter (FADS) integrates droplet generation and acoustic sorting into one device with the ability to uniformly produce droplets and accurately sort single-cell droplets with purity higher than 90%. Meanwhile, the detachable system also prevents samples from cross-contamination and keeps the expensive focused interdigitated transducer reusable.
An acoustic fluorescence-activated droplet sorting (FADS) system that can achieve accurate isolation of single-cell droplets for high-yield single cell sequencing.

Principal investigator, Dr Ai said: “Droplet-based single-cell sequencing is a very powerful tool to study the cellular heterogeneity in diseased tissues for a variety of biological problems. Our developed fluorescence-activated droplet sorter (FADS) is able to encapsulate single-cell droplets and isolate them at 90% accuracy. The presented FADS has resolved the low-yield drawback of existing droplet generation system.”       

This work 'Detachable Acoustophoretic System for Fluorescence-Activated Sorting at the Single-Droplet Level' has been published in Analytical Chemistry, a top-tier journal focused on research in developing original application of analytical methods and results on an important analyte in analytical chemistry. SUTD graduate students, Peixian Li, Zhichao Ma and Yinning Zhou participated in this research project.