Droplet microfluidic technology for single-cell high-throughput screening

doi:10.1073/pnas.0903542106

Droplet microfluidic technology for single-cell high-throughput screening

^aRainDance Technologies, Lexington, MA 02421; and
^bGenetics Department, Harvard Medical School and
^cHoward Hughes Medical Institute, Boston, MA 02115

Edited by Noel A. Clark, University of Colorado, Boulder, CO, and approved June 2, 2009 (received for review March 31, 2009)

Abstract

We present a droplet-based microfluidic technology that enables high-throughput screening of single mammalian cells. This integrated platform allows for the encapsulation of single cells and reagents in independent aqueous microdroplets (1 pL to 10 nL volumes) dispersed in an immiscible carrier oil and enables the digital manipulation of these reactors at a very high-throughput. Here, we validate a full droplet screening workflow by conducting a droplet-based cytotoxicity screen. To perform this screen, we first developed a droplet viability assay that permits the quantitative scoring of cell viability and growth within intact droplets. Next, we demonstrated the high viability of encapsulated human monocytic U937 cells over a period of 4 days. Finally, we developed an optically-coded droplet library enabling the identification of the droplets composition during the assay read-out. Using the integrated droplet technology, we screened a drug library for its cytotoxic effect against U937 cells. Taken together our droplet microfluidic platform is modular, robust, uses no moving parts, and has a wide range of potential applications including high-throughput single-cell analyses, combinatorial screening, and facilitating small sample analyses.

Footnotes

¹To whom correspondence may be addressed: E-mail: brouzese{at}raindancetech.com or ebrouzes{at}genetics.med.harvard.edu
Author contributions: E.B., J.M.R., D.R.L., N.P., and M.L.S. designed research; E.B. and N.S. performed research; E.B., M.M., D.M., M.T., and J.B.H. contributed new reagents/analytic tools; E.B. analyzed data; and E.B. and M.L.S. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS Direct Submission.
This article contains supporting information online at www.pnas.org/cgi/content/full/0903542106/DCSupplemental.