High-throughput and high-resolution flow cytometry in molded microfluidic devices.

Claire Simonnet; Alex Groisman

doi:10.1021/ac060340o

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High-throughput and high-resolution flow cytometry in molded microfluidic devices.

Claire Simonnet·Alex Groisman

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Abstract

We describe the design, fabrication, and operation of two types of flow cytometers based on microfluidic devices made of a single cast of poly(dimethylsiloxane). The stream of particles or cells injected into the devices is hydrodynamically focused in both transverse and lateral directions, has a uniform velocity, and has adjustable diameter and shape. The cytometry system built around the first microfluidic device has fluorescence detection accuracy comparable with that of a commercial flow cytometer and can analyze as many as 17 000 particles/s. This high-throughput microfluidic device could be used in inexpensive stand-alone cytometers or as a part of integrated microanalysis systems. In the second device, a stream of particles is focused to a flow layer of a submicrometer thickness that allows imaging the particles with a high numerical aperture microscope objective. To take long-exposure, low-light fluorescence images of live cells, the device is placed on a moving stage, which accurately balances the translational motion of particles in the flow. The achieved resolution is comparable to that of still micrographs. This high-resolution device could be used for analysis of morphology and fluorescence distribution in cells in continuous flow.

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Flow Cytometry Fluorescence Microfluidic Analytical Techniques Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

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Claire Simonnet, Alex Groisman. 2006-08-15. High-throughput and high-resolution flow cytometry in molded microfluidic devices.. https://doi.org/10.1021/ac060340o

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