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PubMed · 10570146

Sorting by diffusion: an asymmetric obstacle course for continuous molecular separation.

C F Chou·O Bakajin·S W Turner·T A Duke·S S Chan·E C Cox·H G Craighead·R H Austin
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Abstract

A separation technique employing a microfabricated sieve has been demonstrated by observing the motion of DNA molecules of different size. The sieve consists of a two-dimensional lattice of obstacles whose asymmetric disposition rectifies the Brownian motion of molecules driven through the device, causing them to follow paths that depend on their diffusion coefficient. A nominal 6% resolution by length of DNA molecules in the size range 15-30 kbp may be achieved in a 4-inch (10-cm) silicon wafer. The advantage of this method is that samples can be loaded and sorted continuously, in contrast to the batch mode commonly used in gel electrophoresis.

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Chemical FractionationDNADiffusionJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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C F Chou, O Bakajin, S W Turner, T A Duke, S S Chan, E C Cox, H G Craighead, R H Austin. 1999-11-23. Sorting by diffusion: an asymmetric obstacle course for continuous molecular separation.. https://doi.org/10.1073/pnas.96.24.13762

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