High-speed discrimination and sorting of sub-micron particles using a microfluidic device

TL;DR

This paper presents a disposable microfluidic device capable of high-speed, high-fidelity sorting and counting of sub-micron particles and cells using size and fluorescence detection methods, suitable for analysis and manufacturing.

Contribution

It introduces a novel microfluidic sorter integrating resistive pulse sensing and optical imaging for on-demand, high-throughput particle discrimination and sorting.

Findings

Sorting fidelity exceeds 98%.

Can process over 60,000 particles per minute.

Supports both fluorescence and size-based sorting.

Abstract

The size- and fluorescence-based sorting of micro- and nano-scale particles suspended in fluid presents a significant and important challenge for both sample analysis and for manufacturing of nanoparticle-based products. Here we demonstrate a disposable microfluidic particle sorter that enables high-throughput, on-demand counting and binary sorting of sub-micron particles and cells, using either fluorescence or an electrically-based determination of particle size. Size-based sorting uses a resistive pulse sensor integrated on-chip, while fluorescence-based discrimination is achieved using on-the-fly optical image capture and analysis. Following detection and analysis, the individual particles are deflected using a pair of piezoelectric actuators, directing the particles into one of two desired output channels; the main flow goes into a third waste channel. The integrated system can achieve sorting fidelities of better than 98\%, and the mechanism can successfully count and actuate, on demand, more than 60,000 particles/min.